Game Projekt

3 years ago · 9b4eddccf0
128 changed files with 4873 additions and 0 deletions
--- a/.classpath
+++ b/.classpath
@ -0,0 +1,10 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<classpath>
+	<classpathentry kind="src" path="src"/>
+	<classpathentry kind="con" path="org.eclipse.jdt.launching.JRE_CONTAINER"/>
+	<classpathentry kind="con" path="org.eclipse.jdt.junit.JUNIT_CONTAINER/5"/>
+	<classpathentry kind="lib" path="lib/apache-log4j-2.13.3-bin/log4j-1.2-api-2.13.3.jar"/>
+	<classpathentry kind="lib" path="lib/apache-log4j-2.13.3-bin/log4j-api-2.13.3.jar"/>
+	<classpathentry kind="lib" path="lib/apache-log4j-2.13.3-bin/log4j-core-2.13.3.jar"/>
+	<classpathentry kind="output" path="bin"/>
+</classpath>
--- a/.project
+++ b/.project
@ -0,0 +1,17 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<projectDescription>
+	<name>GameProject</name>
+	<comment></comment>
+	<projects>
+	</projects>
+	<buildSpec>
+		<buildCommand>
+			<name>org.eclipse.jdt.core.javabuilder</name>
+			<arguments>
+			</arguments>
+		</buildCommand>
+	</buildSpec>
+	<natures>
+		<nature>org.eclipse.jdt.core.javanature</nature>
+	</natures>
+</projectDescription>
--- a/.settings/org.eclipse.jdt.core.prefs
+++ b/.settings/org.eclipse.jdt.core.prefs
@ -0,0 +1,15 @@
+eclipse.preferences.version=1
+org.eclipse.jdt.core.compiler.codegen.inlineJsrBytecode=enabled
+org.eclipse.jdt.core.compiler.codegen.methodParameters=do not generate
+org.eclipse.jdt.core.compiler.codegen.targetPlatform=12
+org.eclipse.jdt.core.compiler.codegen.unusedLocal=preserve
+org.eclipse.jdt.core.compiler.compliance=12
+org.eclipse.jdt.core.compiler.debug.lineNumber=generate
+org.eclipse.jdt.core.compiler.debug.localVariable=generate
+org.eclipse.jdt.core.compiler.debug.sourceFile=generate
+org.eclipse.jdt.core.compiler.problem.assertIdentifier=error
+org.eclipse.jdt.core.compiler.problem.enablePreviewFeatures=disabled
+org.eclipse.jdt.core.compiler.problem.enumIdentifier=error
+org.eclipse.jdt.core.compiler.problem.reportPreviewFeatures=warning
+org.eclipse.jdt.core.compiler.release=enabled
+org.eclipse.jdt.core.compiler.source=12
--- a/Textdokument.txt
+++ b/Textdokument.txt
--- a/audio/laser.wav
+++ b/audio/laser.wav
--- a/audio/shot.wav
+++ b/audio/shot.wav
--- a/audio/smash.wav
+++ b/audio/smash.wav
--- a/bin/base/GameLoop.class
+++ b/bin/base/GameLoop.class
--- a/bin/base/MultiLevelGame.class
+++ b/bin/base/MultiLevelGame.class
--- a/bin/collider/CircleCollider.class
+++ b/bin/collider/CircleCollider.class
--- a/bin/collider/Collider.class
+++ b/bin/collider/Collider.class
--- a/bin/collider/RectCollider.class
+++ b/bin/collider/RectCollider.class
--- a/bin/controller/CollisionAwareEgoController.class
+++ b/bin/controller/CollisionAwareEgoController.class
--- a/bin/controller/EgoController.class
+++ b/bin/controller/EgoController.class
--- a/bin/controller/EnemyController.class
+++ b/bin/controller/EnemyController.class
--- a/bin/controller/FallingStarController.class
+++ b/bin/controller/FallingStarController.class
--- a/bin/controller/LimitedTimeController.class
+++ b/bin/controller/LimitedTimeController.class
--- a/bin/controller/MineController.class
+++ b/bin/controller/MineController.class
--- a/bin/controller/ObjectController.class
+++ b/bin/controller/ObjectController.class
--- a/bin/controller/SimpleShotController.class
+++ b/bin/controller/SimpleShotController.class
--- a/bin/controller/ZickZackController.class
+++ b/bin/controller/ZickZackController.class
--- a/bin/controller/package-info.class
+++ b/bin/controller/package-info.class
--- a/bin/gameobjects/AnimatedGameobject.class
+++ b/bin/gameobjects/AnimatedGameobject.class
--- a/bin/gameobjects/EgoObject.class
+++ b/bin/gameobjects/EgoObject.class
--- a/bin/gameobjects/FallingStar.class
+++ b/bin/gameobjects/FallingStar.class
--- a/bin/gameobjects/GameObject.class
+++ b/bin/gameobjects/GameObject.class
--- a/bin/gameobjects/RectObject.class
+++ b/bin/gameobjects/RectObject.class
--- a/bin/gameobjects/TextObject.class
+++ b/bin/gameobjects/TextObject.class
--- a/bin/log4j2.xml
+++ b/bin/log4j2.xml
@ -0,0 +1,30 @@
+<?xml version="1.0" encoding="UTF-8"?>
+
+<configuration status="OFF">
+	<appenders>
+		
+		<Console name="Console" target="SYSTEM_OUT">
+			<PatternLayout pattern="%d %-5level %logger{36} - %msg%n" />
+		</Console>
+		
+		<File name="File" fileName="log\log4j.log">
+			<PatternLayout pattern="%d %-5level %logger{36} - %msg%n" />
+		</File>
+		
+	</appenders>
+	
+	<loggers>
+	
+		<root level="warn">
+			<appender-ref ref="Console" />
+			<appender-ref ref="File" />
+		</root>
+		
+		<Logger name="base.GameLoop" level="info">      		
+    	</Logger>
+    	
+    	<Logger name="playground" level="info">      		
+    	</Logger>
+		
+	</loggers>
+</configuration>
--- a/bin/playground/Animation.class
+++ b/bin/playground/Animation.class
--- a/bin/playground/HighscoreManager.class
+++ b/bin/playground/HighscoreManager.class
--- a/bin/playground/Level1.class
+++ b/bin/playground/Level1.class
--- a/bin/playground/Level2.class
+++ b/bin/playground/Level2.class
--- a/bin/playground/Level3.class
+++ b/bin/playground/Level3.class
--- a/bin/playground/Level4.class
+++ b/bin/playground/Level4.class
--- a/bin/playground/LevelBoss.class
+++ b/bin/playground/LevelBoss.class
--- a/bin/playground/LevelHitTwice.class
+++ b/bin/playground/LevelHitTwice.class
--- a/bin/playground/Music$1.class
+++ b/bin/playground/Music$1.class
--- a/bin/playground/Music.class
+++ b/bin/playground/Music.class
--- a/bin/playground/Playground.class
+++ b/bin/playground/Playground.class
--- a/bin/playground/SaveGame.class
+++ b/bin/playground/SaveGame.class
--- a/bin/playground/SpaceInvadersLevel.class
+++ b/bin/playground/SpaceInvadersLevel.class
--- a/bin/playground/SpaceInvadersLevelTest.class
+++ b/bin/playground/SpaceInvadersLevelTest.class
--- a/bin/rendering/AnimationArtist.class
+++ b/bin/rendering/AnimationArtist.class
--- a/bin/rendering/Artist.class
+++ b/bin/rendering/Artist.class
--- a/bin/rendering/CircleArtist.class
+++ b/bin/rendering/CircleArtist.class
--- a/bin/rendering/RectArtist.class
+++ b/bin/rendering/RectArtist.class
--- a/bin/rendering/TextArtist.class
+++ b/bin/rendering/TextArtist.class
--- a/bin/ui/AboutFrame$1.class
+++ b/bin/ui/AboutFrame$1.class
--- a/bin/ui/AboutFrame.class
+++ b/bin/ui/AboutFrame.class
--- a/bin/ui/GamePanel.class
+++ b/bin/ui/GamePanel.class
--- a/bin/ui/GameUI.class
+++ b/bin/ui/GameUI.class
--- a/highscore.txt
+++ b/highscore.txt
@ -0,0 +1 @@
+22500
--- a/lib/apache-log4j-2.13.3-bin/LICENSE.txt
+++ b/lib/apache-log4j-2.13.3-bin/LICENSE.txt
@ -0,0 +1,202 @@
+
+                                 Apache License
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--- a/lib/apache-log4j-2.13.3-bin/NOTICE.txt
+++ b/lib/apache-log4j-2.13.3-bin/NOTICE.txt
@ -0,0 +1,17 @@
+Apache Log4j
+Copyright 1999-2017 Apache Software Foundation
+
+This product includes software developed at
+The Apache Software Foundation (http://www.apache.org/).
+
+ResolverUtil.java
+Copyright 2005-2006 Tim Fennell
+
+Dumbster SMTP test server
+Copyright 2004 Jason Paul Kitchen
+
+TypeUtil.java
+Copyright 2002-2012 Ramnivas Laddad, Juergen Hoeller, Chris Beams
+
+picocli (http://picocli.info)
+Copyright 2017 Remko Popma
--- a/lib/apache-log4j-2.13.3-bin/RELEASE-NOTES.md
+++ b/lib/apache-log4j-2.13.3-bin/RELEASE-NOTES.md
@ -0,0 +1,60 @@
+<!---
+ Licensed to the Apache Software Foundation (ASF) under one or more
+ contributor license agreements.  See the NOTICE file distributed with
+ this work for additional information regarding copyright ownership.
+ The ASF licenses this file to You under the Apache License, Version 2.0
+ (the "License"); you may not use this file except in compliance with
+ the License.  You may obtain a copy of the License at
+
+      http://www.apache.org/licenses/LICENSE-2.0
+
+ Unless required by applicable law or agreed to in writing, software
+ distributed under the License is distributed on an "AS IS" BASIS,
+ WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ See the License for the specific language governing permissions and
+ limitations under the License.
+-->
+# Apache Log4j 2.13.3 Release Notes
+
+The Apache Log4j 2 team is pleased to announce the Log4j 2.13.3 release!
+
+Apache Log4j is a well known framework for logging application behavior. Log4j 2 is an upgrade
+to Log4j that provides significant improvements over its predecessor, Log4j 1.x, and provides
+many other modern features such as support for Markers, lambda expressions for lazy logging,
+property substitution using Lookups, multiple patterns on a PatternLayout and asynchronous
+Loggers. Another notable Log4j 2 feature is the ability to be "garbage-free" (avoid allocating
+temporary objects) while logging. In addition, Log4j 2 will not lose events while reconfiguring.
+
+The artifacts may be downloaded from https://logging.apache.org/log4j/2.x/download.html.
+
+This release contains a fix for bug LOG4J2-2838.
+
+Due to a break in compatibility in the SLF4J binding, Log4j now ships with two versions of the SLF4J to Log4j adapters.
+log4j-slf4j-impl should be used with SLF4J 1.7.x and earlier and log4j-slf4j18-impl should be used with SLF4J 1.8.x and
+later.
+
+Note that the default XML, JSON and YAML formats changed in the 2.11.0 release: they no longer have the "timeMillis"
+attribute and instead have an "Instant" element with "epochSecond" and "nanoOfSecond" attributes. If the previous
+behavior is desired the "includeTimeMillis" attribute may be set to true on each of the respective Layouts.
+
+The Log4j 2.13.3 API, as well as many core components, maintains binary compatibility with previous releases.
+
+## GA Release 2.13.3
+
+Changes in this version include:
+
+
+### Fixed Bugs
+* [LOG4J2-2838](https://issues.apache.org/jira/browse/LOG4J2-2838):
+Fix NullPointerException in ThreadContextDataInjector.
+
+
+---
+
+Apache Log4j 2.13.3 requires a minimum of Java 8 to build and run. Log4j 2.3 was the
+last release that supported Java 6 and Log4j 2.12.1 is the last release to support Java 7.
+
+For complete information on Apache Log4j 2, including instructions on how to submit bug
+reports, patches, or suggestions for improvement, see the Apache Apache Log4j 2 website:
+
+https://logging.apache.org/log4j/2.x/
--- a/lib/apache-log4j-2.13.3-bin/log4j-1.2-api-2.13.3.jar
+++ b/lib/apache-log4j-2.13.3-bin/log4j-1.2-api-2.13.3.jar
--- a/lib/apache-log4j-2.13.3-bin/log4j-api-2.13.3.jar
+++ b/lib/apache-log4j-2.13.3-bin/log4j-api-2.13.3.jar
--- a/lib/apache-log4j-2.13.3-bin/log4j-core-2.13.3.jar
+++ b/lib/apache-log4j-2.13.3-bin/log4j-core-2.13.3.jar
--- a/log/log4j.log
+++ b/log/log4j.log
@ -0,0 +1,185 @@
+2022-04-24 15:15:37,957 INFO  base.GameLoop - GUI starts
+2022-04-24 15:15:43,111 INFO  base.GameLoop - GUI NEW
+2022-04-24 15:15:43,111 INFO  playground.SpaceInvadersLevel - PREPARE
+2022-04-24 15:15:43,144 INFO  playground.Animation - img added .\video/sweetAlien0.png
+2022-04-24 15:15:43,147 INFO  playground.Animation - img added .\video/sweetAlien1.png
+2022-04-24 15:15:43,148 INFO  playground.Animation - img added .\video/sweetAlien2.png
+2022-04-24 15:15:43,150 INFO  playground.Animation - img added .\video/sweetAlien3.png
+2022-04-24 15:15:43,151 INFO  playground.Animation - img added .\video/sweetAlien4.png
+2022-04-24 15:15:43,153 INFO  playground.Animation - img added .\video/sweetAlien5.png
+2022-04-24 15:15:43,154 INFO  playground.Animation - img added .\video/sweetAlien6.png
+2022-04-24 15:15:43,156 INFO  playground.Animation - img added .\video/sweetAlien7.png
+2022-04-24 15:15:43,159 INFO  playground.Animation - img added .\video/heart0.png
+2022-04-24 15:15:43,160 INFO  playground.Animation - img added .\video/heart1.png
+2022-04-24 15:15:43,161 WARN  playground.HighscoreManager - WARNING: Highscore file was not found and reset
+2022-04-24 15:15:43,162 INFO  playground.HighscoreManager - Highscore file was opened and saved score: 0
+2022-04-24 15:15:43,164 INFO  playground.SpaceInvadersLevel - HIGHSCORE0
+2022-04-24 15:16:28,157 INFO  base.GameLoop - GUI NEW
+2022-04-24 15:16:28,158 INFO  playground.SpaceInvadersLevel - PREPARE
+2022-04-24 15:16:28,159 INFO  playground.SpaceInvadersLevel - HIGHSCORE0
+2022-04-24 15:16:47,660 INFO  base.GameLoop - GUI NEW
+2022-04-24 15:16:47,660 INFO  playground.SpaceInvadersLevel - PREPARE
+2022-04-24 15:16:47,661 INFO  playground.SpaceInvadersLevel - HIGHSCORE0
+2022-04-24 15:16:48,868 INFO  base.GameLoop - GUI NEW
+2022-04-24 15:16:48,869 INFO  playground.SpaceInvadersLevel - PREPARE
+2022-04-24 15:16:48,869 INFO  playground.SpaceInvadersLevel - HIGHSCORE0
+2022-04-24 15:16:50,412 INFO  base.GameLoop - GUI PAUSE
+2022-04-24 15:16:52,109 INFO  base.GameLoop - GUI NEW
+2022-04-24 15:16:52,109 INFO  playground.SpaceInvadersLevel - PREPARE
+2022-04-24 15:16:52,110 INFO  playground.SpaceInvadersLevel - HIGHSCORE0
+2022-04-24 15:16:53,652 INFO  base.GameLoop - GUI NEW
+2022-04-24 15:16:53,652 INFO  playground.SpaceInvadersLevel - PREPARE
+2022-04-24 15:16:53,653 INFO  playground.SpaceInvadersLevel - HIGHSCORE0
+2022-04-24 15:16:54,315 INFO  base.GameLoop - GUI NEW
+2022-04-24 15:16:54,315 INFO  playground.SpaceInvadersLevel - PREPARE
+2022-04-24 15:16:54,316 INFO  playground.SpaceInvadersLevel - HIGHSCORE0
+2022-04-24 15:16:58,388 INFO  base.GameLoop - GUI starts
+2022-04-24 15:17:00,103 INFO  base.GameLoop - GUI NEW
+2022-04-24 15:17:00,104 INFO  playground.SpaceInvadersLevel - PREPARE
+2022-04-24 15:17:00,130 INFO  playground.Animation - img added .\video/sweetAlien0.png
+2022-04-24 15:17:00,133 INFO  playground.Animation - img added .\video/sweetAlien1.png
+2022-04-24 15:17:00,135 INFO  playground.Animation - img added .\video/sweetAlien2.png
+2022-04-24 15:17:00,136 INFO  playground.Animation - img added .\video/sweetAlien3.png
+2022-04-24 15:17:00,138 INFO  playground.Animation - img added .\video/sweetAlien4.png
+2022-04-24 15:17:00,139 INFO  playground.Animation - img added .\video/sweetAlien5.png
+2022-04-24 15:17:00,140 INFO  playground.Animation - img added .\video/sweetAlien6.png
+2022-04-24 15:17:00,141 INFO  playground.Animation - img added .\video/sweetAlien7.png
+2022-04-24 15:17:00,144 INFO  playground.Animation - img added .\video/heart0.png
+2022-04-24 15:17:00,146 INFO  playground.Animation - img added .\video/heart1.png
+2022-04-24 15:17:00,149 INFO  playground.SpaceInvadersLevel - HIGHSCORE0
+2022-04-24 15:17:26,519 INFO  playground.HighscoreManager - Highscore file was opened and saved score: 6000
+2022-04-24 15:17:26,519 INFO  playground.SpaceInvadersLevel - no enemies left, level done.
+2022-04-24 15:17:26,520 INFO  base.GameLoop - reached end of levels
+2022-04-24 15:17:26,520 INFO  base.GameLoop - Game ends. Bye.
+2022-04-24 15:20:47,899 INFO  base.GameLoop - GUI starts
+2022-04-24 15:20:54,103 INFO  base.GameLoop - GUI NEW
+2022-04-24 15:20:54,104 INFO  playground.SpaceInvadersLevel - PREPARE
+2022-04-24 15:20:54,135 INFO  playground.Animation - img added .\video/sweetAlien0.png
+2022-04-24 15:20:54,138 INFO  playground.Animation - img added .\video/sweetAlien1.png
+2022-04-24 15:20:54,140 INFO  playground.Animation - img added .\video/sweetAlien2.png
+2022-04-24 15:20:54,142 INFO  playground.Animation - img added .\video/sweetAlien3.png
+2022-04-24 15:20:54,144 INFO  playground.Animation - img added .\video/sweetAlien4.png
+2022-04-24 15:20:54,145 INFO  playground.Animation - img added .\video/sweetAlien5.png
+2022-04-24 15:20:54,147 INFO  playground.Animation - img added .\video/sweetAlien6.png
+2022-04-24 15:20:54,148 INFO  playground.Animation - img added .\video/sweetAlien7.png
+2022-04-24 15:20:54,151 INFO  playground.Animation - img added .\video/heart0.png
+2022-04-24 15:20:54,153 INFO  playground.Animation - img added .\video/heart1.png
+2022-04-24 15:20:54,155 INFO  playground.SpaceInvadersLevel - HIGHSCORE6000
+2022-04-24 15:21:22,977 INFO  playground.SpaceInvadersLevel - no enemies left, level done.
+2022-04-24 15:21:22,977 INFO  base.GameLoop - reached end of levels
+2022-04-24 15:21:22,977 INFO  base.GameLoop - Game ends. Bye.
+2022-04-24 15:28:41,348 INFO  base.GameLoop - GUI starts
+2022-04-24 15:28:43,030 INFO  base.GameLoop - GUI NEW
+2022-04-24 15:28:43,030 INFO  playground.SpaceInvadersLevel - PREPARE
+2022-04-24 15:28:43,058 INFO  playground.Animation - img added .\video/sweetAlien0.png
+2022-04-24 15:28:43,062 INFO  playground.Animation - img added .\video/sweetAlien1.png
+2022-04-24 15:28:43,063 INFO  playground.Animation - img added .\video/sweetAlien2.png
+2022-04-24 15:28:43,064 INFO  playground.Animation - img added .\video/sweetAlien3.png
+2022-04-24 15:28:43,065 INFO  playground.Animation - img added .\video/sweetAlien4.png
+2022-04-24 15:28:43,067 INFO  playground.Animation - img added .\video/sweetAlien5.png
+2022-04-24 15:28:43,068 INFO  playground.Animation - img added .\video/sweetAlien6.png
+2022-04-24 15:28:43,069 INFO  playground.Animation - img added .\video/sweetAlien7.png
+2022-04-24 15:28:43,071 INFO  playground.Animation - img added .\video/heart0.png
+2022-04-24 15:28:43,073 INFO  playground.Animation - img added .\video/heart1.png
+2022-04-24 15:28:43,076 INFO  playground.SpaceInvadersLevel - HIGHSCORE6000
+2022-04-24 15:28:56,264 INFO  playground.SpaceInvadersLevel - no enemies left, level done.
+2022-04-24 15:28:56,265 INFO  playground.SpaceInvadersLevel - PREPARE
+2022-04-24 15:28:56,267 INFO  playground.Animation - img added .\video/sweetAlien0.png
+2022-04-24 15:28:56,268 INFO  playground.Animation - img added .\video/sweetAlien1.png
+2022-04-24 15:28:56,269 INFO  playground.Animation - img added .\video/sweetAlien2.png
+2022-04-24 15:28:56,270 INFO  playground.Animation - img added .\video/sweetAlien3.png
+2022-04-24 15:28:56,272 INFO  playground.Animation - img added .\video/sweetAlien4.png
+2022-04-24 15:28:56,273 INFO  playground.Animation - img added .\video/sweetAlien5.png
+2022-04-24 15:28:56,274 INFO  playground.Animation - img added .\video/sweetAlien6.png
+2022-04-24 15:28:56,275 INFO  playground.Animation - img added .\video/sweetAlien7.png
+2022-04-24 15:28:56,277 INFO  playground.Animation - img added .\video/heart0.png
+2022-04-24 15:28:56,278 INFO  playground.Animation - img added .\video/heart1.png
+2022-04-24 15:28:56,279 INFO  playground.SpaceInvadersLevel - HIGHSCORE6000
+2022-04-24 15:29:17,828 INFO  playground.HighscoreManager - Highscore file was opened and saved score: 12000
+2022-04-24 15:29:17,828 INFO  playground.SpaceInvadersLevel - no enemies left, level done.
+2022-04-24 15:29:17,828 INFO  playground.SpaceInvadersLevel - PREPARE
+2022-04-24 15:29:17,830 INFO  playground.Animation - img added .\video/sweetAlien0.png
+2022-04-24 15:29:17,831 INFO  playground.Animation - img added .\video/sweetAlien1.png
+2022-04-24 15:29:17,832 INFO  playground.Animation - img added .\video/sweetAlien2.png
+2022-04-24 15:29:17,833 INFO  playground.Animation - img added .\video/sweetAlien3.png
+2022-04-24 15:29:17,834 INFO  playground.Animation - img added .\video/sweetAlien4.png
+2022-04-24 15:29:17,835 INFO  playground.Animation - img added .\video/sweetAlien5.png
+2022-04-24 15:29:17,835 INFO  playground.Animation - img added .\video/sweetAlien6.png
+2022-04-24 15:29:17,836 INFO  playground.Animation - img added .\video/sweetAlien7.png
+2022-04-24 15:29:17,838 INFO  playground.Animation - img added .\video/heart0.png
+2022-04-24 15:29:17,839 INFO  playground.Animation - img added .\video/heart1.png
+2022-04-24 15:29:17,840 INFO  playground.SpaceInvadersLevel - HIGHSCORE12000
+2022-04-24 15:29:52,038 INFO  playground.HighscoreManager - Highscore file was opened and saved score: 17500
+2022-04-24 15:29:52,038 INFO  playground.SpaceInvadersLevel - no enemies left, level done.
+2022-04-24 15:29:52,038 INFO  playground.SpaceInvadersLevel - PREPARE
+2022-04-24 15:29:52,040 INFO  playground.Animation - img added .\video/sweetAlien0.png
+2022-04-24 15:29:52,041 INFO  playground.Animation - img added .\video/sweetAlien1.png
+2022-04-24 15:29:52,042 INFO  playground.Animation - img added .\video/sweetAlien2.png
+2022-04-24 15:29:52,043 INFO  playground.Animation - img added .\video/sweetAlien3.png
+2022-04-24 15:29:52,043 INFO  playground.Animation - img added .\video/sweetAlien4.png
+2022-04-24 15:29:52,044 INFO  playground.Animation - img added .\video/sweetAlien5.png
+2022-04-24 15:29:52,045 INFO  playground.Animation - img added .\video/sweetAlien6.png
+2022-04-24 15:29:52,046 INFO  playground.Animation - img added .\video/sweetAlien7.png
+2022-04-24 15:29:52,048 INFO  playground.Animation - img added .\video/heart0.png
+2022-04-24 15:29:52,049 INFO  playground.Animation - img added .\video/heart1.png
+2022-04-24 15:29:52,049 INFO  playground.SpaceInvadersLevel - HIGHSCORE17500
+2022-04-24 15:30:16,985 INFO  playground.HighscoreManager - Highscore file was opened and saved score: 22500
+2022-04-24 15:30:16,985 INFO  playground.SpaceInvadersLevel - no enemies left, level done.
+2022-04-24 15:30:16,985 INFO  base.GameLoop - reached end of levels
+2022-04-24 15:30:16,985 INFO  base.GameLoop - Game ends. Bye.
+2022-04-24 15:32:41,524 INFO  base.GameLoop - GUI starts
+2022-04-24 15:32:42,806 INFO  base.GameLoop - GUI NEW
+2022-04-24 15:32:42,807 INFO  playground.SpaceInvadersLevel - PREPARE
+2022-04-24 15:32:42,835 INFO  playground.Animation - img added .\video/sweetAlien0.png
+2022-04-24 15:32:42,838 INFO  playground.Animation - img added .\video/sweetAlien1.png
+2022-04-24 15:32:42,839 INFO  playground.Animation - img added .\video/sweetAlien2.png
+2022-04-24 15:32:42,841 INFO  playground.Animation - img added .\video/sweetAlien3.png
+2022-04-24 15:32:42,842 INFO  playground.Animation - img added .\video/sweetAlien4.png
+2022-04-24 15:32:42,844 INFO  playground.Animation - img added .\video/sweetAlien5.png
+2022-04-24 15:32:42,845 INFO  playground.Animation - img added .\video/sweetAlien6.png
+2022-04-24 15:32:42,846 INFO  playground.Animation - img added .\video/sweetAlien7.png
+2022-04-24 15:32:42,849 INFO  playground.Animation - img added .\video/heart0.png
+2022-04-24 15:32:42,850 INFO  playground.Animation - img added .\video/heart1.png
+2022-04-24 15:32:42,852 INFO  playground.SpaceInvadersLevel - HIGHSCORE22500
+2022-04-24 15:32:57,951 INFO  playground.SpaceInvadersLevel - no enemies left, level done.
+2022-04-24 15:32:57,952 INFO  playground.SpaceInvadersLevel - PREPARE
+2022-04-24 15:32:57,954 INFO  playground.Animation - img added .\video/sweetAlien0.png
+2022-04-24 15:32:57,956 INFO  playground.Animation - img added .\video/sweetAlien1.png
+2022-04-24 15:32:57,957 INFO  playground.Animation - img added .\video/sweetAlien2.png
+2022-04-24 15:32:57,958 INFO  playground.Animation - img added .\video/sweetAlien3.png
+2022-04-24 15:32:57,959 INFO  playground.Animation - img added .\video/sweetAlien4.png
+2022-04-24 15:32:57,960 INFO  playground.Animation - img added .\video/sweetAlien5.png
+2022-04-24 15:32:57,961 INFO  playground.Animation - img added .\video/sweetAlien6.png
+2022-04-24 15:32:57,962 INFO  playground.Animation - img added .\video/sweetAlien7.png
+2022-04-24 15:32:57,964 INFO  playground.Animation - img added .\video/heart0.png
+2022-04-24 15:32:57,965 INFO  playground.Animation - img added .\video/heart1.png
+2022-04-24 15:32:57,966 INFO  playground.SpaceInvadersLevel - HIGHSCORE22500
+2022-04-24 15:33:11,120 INFO  playground.SpaceInvadersLevel - no enemies left, level done.
+2022-04-24 15:33:11,120 INFO  playground.SpaceInvadersLevel - PREPARE
+2022-04-24 15:33:11,123 INFO  playground.Animation - img added .\video/sweetAlien0.png
+2022-04-24 15:33:11,124 INFO  playground.Animation - img added .\video/sweetAlien1.png
+2022-04-24 15:33:11,124 INFO  playground.Animation - img added .\video/sweetAlien2.png
+2022-04-24 15:33:11,125 INFO  playground.Animation - img added .\video/sweetAlien3.png
+2022-04-24 15:33:11,126 INFO  playground.Animation - img added .\video/sweetAlien4.png
+2022-04-24 15:33:11,127 INFO  playground.Animation - img added .\video/sweetAlien5.png
+2022-04-24 15:33:11,128 INFO  playground.Animation - img added .\video/sweetAlien6.png
+2022-04-24 15:33:11,129 INFO  playground.Animation - img added .\video/sweetAlien7.png
+2022-04-24 15:33:11,131 INFO  playground.Animation - img added .\video/heart0.png
+2022-04-24 15:33:11,132 INFO  playground.Animation - img added .\video/heart1.png
+2022-04-24 15:33:11,133 INFO  playground.SpaceInvadersLevel - HIGHSCORE22500
+2022-04-24 15:33:28,392 INFO  playground.SpaceInvadersLevel - no enemies left, level done.
+2022-04-24 15:33:28,392 INFO  playground.SpaceInvadersLevel - PREPARE
+2022-04-24 15:33:28,394 INFO  playground.Animation - img added .\video/sweetAlien0.png
+2022-04-24 15:33:28,395 INFO  playground.Animation - img added .\video/sweetAlien1.png
+2022-04-24 15:33:28,396 INFO  playground.Animation - img added .\video/sweetAlien2.png
+2022-04-24 15:33:28,397 INFO  playground.Animation - img added .\video/sweetAlien3.png
+2022-04-24 15:33:28,398 INFO  playground.Animation - img added .\video/sweetAlien4.png
+2022-04-24 15:33:28,399 INFO  playground.Animation - img added .\video/sweetAlien5.png
+2022-04-24 15:33:28,399 INFO  playground.Animation - img added .\video/sweetAlien6.png
+2022-04-24 15:33:28,400 INFO  playground.Animation - img added .\video/sweetAlien7.png
+2022-04-24 15:33:28,402 INFO  playground.Animation - img added .\video/heart0.png
+2022-04-24 15:33:28,403 INFO  playground.Animation - img added .\video/heart1.png
+2022-04-24 15:33:28,404 INFO  playground.SpaceInvadersLevel - HIGHSCORE22500
+2022-04-24 15:33:34,404 INFO  playground.SpaceInvadersLevel - no enemies left, level done.
+2022-04-24 15:33:34,404 INFO  base.GameLoop - reached end of levels
+2022-04-24 15:33:34,404 INFO  base.GameLoop - Game ends. Bye.
--- a/src/base/GameLoop.java
+++ b/src/base/GameLoop.java
@ -0,0 +1,231 @@
+package base;
+
+import java.io.IOException;
+import java.util.ArrayList;
+import java.util.List;
+import java.util.ListIterator;
+import org.apache.logging.log4j.LogManager;
+import org.apache.logging.log4j.Logger;
+import gameobjects.GameObject;
+import playground.Level1;
+import playground.Playground;
+import ui.GameUI;
+
+
+/**
+ * Main class starting any game, contains main(). Apart from that, this class manages all
+ * non-logical functionalities which should be hidden from a game designer like:
+ * <ul>
+ * <li>Setting up windows, panels, buttons, action callbacks, ...
+ * <li>Reading keyboard inputs
+ * <li>Redrawing game window if necessary
+ * <li>managing the game time and calling the appropriate {@link GameObject} or {@link Playground}
+ * methods periodically, at every time step of the game.
+ * </ul>
+ * There will normally never be a need to modify this file, a designer/game programmer should always
+ * redefine the {@link GameObject} and {@link Playground} classes and implement new functionality
+ * there. To make a long story short<br>
+ */
+public class GameLoop {
+
+  /** Pixel width of Game GUI ( above 0) */
+  public static int SIZEX = 300;
+  /** Pixel height of Game GUI (above 0) */
+  public static int SIZEY = 200;
+
+   /**
+    *  before call to {@link #runGame(String[])} this List should be initialized (in constructor).
+   */
+  private List<Playground> levels = new ArrayList<Playground>(0);
+
+  private static Logger logger = LogManager.getLogger(GameLoop.class);
+
+  /** constructor which calls {@link #defineLevels()}, which adds all levels of this game. 
+   */
+  public GameLoop() {    
+    this.defineLevels();
+  }
+  
+  /**
+   * First resets (clears) the already existing level instances of this game's list of levels ({@link #resetLevels()}), 
+   * then adds one instance of {@link Level1} by calling {@link #addLevel()}. 
+   * Should be called only before playing starts (e.g. in constructor or before {@link #runGame(String[]) } is called.
+   * 
+   * <br><strong>Note:</strong> Subclasses of {@link GameLoop} should override this method to define own levels for their game.
+   */
+  void defineLevels() {  
+    this.resetLevels();
+    this.addLevel(new Level1());
+  }
+  
+  /**
+   * Adds the given level instance to the end of the currently already stored list of levels to play.
+   * Should be called only before playing starts (e.g. in constructor or before {@link #runGame(String[]) } is called.
+   * 
+   * @param level instance of Playground (a level) to add.
+   */
+  void addLevel(Playground level) {
+    this.levels.add(level);
+  }
+  
+  /**
+   *  Removes all levels from the list of levels to play! Do not call this method while {@link #runGame(String[]) } is running!
+   */
+  void resetLevels() {
+    this.levels.clear();
+  }
+
+
+  /**
+   * loops over all {@link #levels} and implements the game loop to update continuously the level
+   * during play time
+   *
+   * @param args command line arguments forwarded (currently ignored)
+   * @throws IOException if hitghscore.txt cannot be written.
+   */
+  public void runGame(String[] args) throws IOException {
+
+    logger.info("GUI starts");
+    GameUI gameUI = new GameUI(SIZEX, SIZEY);   // probably change to your new GUI class
+
+    double gameTime = -1;
+    Playground currentPlayground = null;
+
+    // loop over different levels
+    ListIterator<Playground> levelIterator = levels.listIterator();
+    while (true) {
+      logger.debug("LevelIndex is " + (levelIterator.nextIndex()) + " (of " + levels.size() + " levels)");
+      gameTime = 0;
+      long start = System.nanoTime();
+      
+      // loop over single level
+      while (true) {
+
+        int act = GameUI.getNewAction();
+
+        // Query GameUI for high-level user commands; new game/reset/etc...
+        if (act == GameUI.ACTION_RESET) {
+          // ReStart Game in same Level
+          logger.info("GUI RESET");          
+          currentPlayground.prepareLevel("level" + (levelIterator.nextIndex()-1));
+          GameUI.resetAction();
+        }
+
+        if (act == GameUI.ACTION_NEW) {
+          // new game
+          logger.info("GUI NEW");
+          start = System.nanoTime();
+          levelIterator = levels.listIterator(); // reset
+          currentPlayground = levelIterator.next(); // again level
+          currentPlayground.prepareLevel("level" + (levelIterator.nextIndex()-1));
+          gameUI.setPlayground(currentPlayground);          
+          GameUI.resetAction();
+          break;
+        }
+
+        if (act == GameUI.ACTION_BUTTON) {
+          // Event of Button pressed --> PAUSE!
+          logger.info("GUI PAUSE");
+          if (currentPlayground != null) {
+            boolean p = currentPlayground.isPaused();
+            p = !p;
+            currentPlayground.setPaused(p);
+          }
+          GameUI.resetAction();
+        }
+
+        if (act == GameUI.ACTION_SAVE) {
+          logger.info("GUI SAVE");
+          // UNDONE save current state (not yet working/implemented)
+          GameUI.resetAction();
+        }
+
+        if (act == GameUI.ACTION_LOAD) {
+          logger.info("GUI LOAD");
+          // load game state (currently simply resets)
+          GameUI.resetAction();
+        }
+
+        // if game has been created: execute a single iteration of the game loop
+        if (currentPlayground != null) {
+          // calc time that was used for painting the game, in seconds since last loop
+          long end = System.nanoTime();
+          double realTS = ((double) (end - start) / 1000000000.);
+          
+          // time calc for one loop of the while
+          start = System.nanoTime();
+          
+          
+          
+          if (currentPlayground.levelFinished() || currentPlayground.gameOver() == true) {
+            break; // leave level; breaks WHILE
+          }
+
+          // paint current state of level and start time measurement          
+          gameUI.waitWhilePainting();
+
+
+          gameUI.grabFocus(); // needed to grab input events in next step
+
+          // communicate inputs to level
+          currentPlayground.processKeyEvents(gameUI.getKeyEvents());
+          currentPlayground.processMouseEvents(gameUI.getMouseEvents());
+
+          if (currentPlayground.isPaused() == false) {
+            
+            // update objects and level
+            currentPlayground.updateObjects();
+            currentPlayground.applyGameLogic();
+            
+
+            // update game time
+            gameTime += realTS;             
+            // communicate gameTime and timestep to level
+            currentPlayground.setTimestep(realTS);
+            currentPlayground.setGameTime(gameTime);
+            Playground.setGlobalFlag("gameTime", Double.valueOf(realTS));
+            logger.trace("gameTime is now "+gameTime);
+
+          } // if
+        } // if
+
+      } // inner while loop within level
+
+      // after level is done: leave outer loop if game over
+      if (currentPlayground.gameOver() == true) {
+        break; // outer while ends game
+      }
+
+      // after level is done: reset level and go to next, if there is one
+      if (currentPlayground.levelFinished() == true) {
+        currentPlayground.reset();
+
+        // increase level counter, go on to next one        
+        logger.debug("level finished. now new LevelIndex is " + levelIterator.nextIndex());
+        if (levelIterator.nextIndex() >= levels.size()) {
+          logger.info("reached end of levels");
+          break; // outer while ends game;
+        }
+        currentPlayground = levelIterator.next();
+        currentPlayground.prepareLevel("level" + (levelIterator.nextIndex()-1));
+      }
+
+    } // outer loop over levels
+    logger.info("Game ends. Bye.");
+    System.exit(0);
+  } // main()
+
+
+  /**
+   * main to start the whole application.
+   * initializes the {@link #levels} ArrayList of Playground instances (levels) to be played with one level {@link SpaceInvadersLevel} in constructor of {@link #GameLoop}.
+   * 
+   * @param args Java default command line args, forwarded to {@link #runGame(String[])}
+   * @throws IOException in case highscore.txt cannot be written.
+   */
+  public static void main(String[] args) throws IOException {
+    GameLoop gl = new GameLoop();    
+    gl.runGame(args);
+  }
+
+}
--- a/src/base/MultiLevelGame.java
+++ b/src/base/MultiLevelGame.java
@ -0,0 +1,30 @@
+//Coding Team 66
+package base;
+
+import java.io.IOException;
+
+//importieren der neuen Level aus dem Package Playground
+import playground.Level1;
+import playground.Level3;
+import playground.LevelBoss;
+import playground.LevelHitTwice;
+
+
+public class MultiLevelGame extends GameLoop{
+	
+	//main wie bei GameLoop, nur das stattdessen Instanz von MulitLevelGame erstellt wird
+	public static void main(String[] args) throws IOException {
+	    MultiLevelGame gl = new MultiLevelGame();    
+	    gl.runGame(args);
+	  }
+	
+	@Override //Überschreiben der Methode defineLevels 
+	void defineLevels() {  
+	    this.resetLevels();
+	    this.addLevel(new Level1());
+	    this.addLevel(new LevelHitTwice());
+	    this.addLevel(new Level3());
+	    this.addLevel(new LevelBoss());
+	  }
+	
+}
--- a/src/collider/CircleCollider.java
+++ b/src/collider/CircleCollider.java
@ -0,0 +1,88 @@
+package collider;
+
+import java.awt.Color;
+import gameobjects.*;
+import org.apache.logging.log4j.Logger;
+import org.apache.logging.log4j.LogManager;
+
+
+/** Collider for round objects */
+public class CircleCollider extends Collider {
+
+  double x;
+  double y;
+  double vx;
+  double vy;
+
+  double r;
+
+  private static Logger logger = LogManager.getLogger(Collider.class);
+  
+  /**
+   * Constructor which sets the radius to be respected for collisions.
+   * 
+   * @param id String unique name for the collider instance
+   * @param o GameObject it belongs to
+   * @param radius radius in pixels to use as a size
+   */
+  public CircleCollider(String id, GameObject o, double radius) {
+
+    super(id, o);
+    this.r = radius;
+  }
+
+  /** simple concatenation of all attributes (x,y,r) */
+  public String toString() {
+    return "circ:" + x + " " + y + "/" + r + " ";
+  }
+
+
+  /**
+   * calculates the collission of this with other collider
+   * 
+   * @param _c2 the other collider
+   * @return true if a collision was detected
+   * @throws Exception in case the math operations are invalid (due to illegal values of x y or
+   *         radius)
+   */
+  public boolean checkCollisionCircCirc(Collider _c2) throws Exception {
+    CircleCollider c2 = (CircleCollider) _c2;
+    CircleCollider c1 = this;
+    logger.trace(c1.x + " " + c1.y + " " + c1.r + " " + c2.x + " " + c2.y+ " " + c2.r);
+    int kathete1 = (int) (Math.abs(c2.gameobject.getX() - c1.gameobject.getX()));
+    int kathete2 = (int) (Math.abs(c2.gameobject.getX() - c1.gameobject.getY()));
+    int hypothenuse = (int) (c1.r + c2.r);
+
+    logger.trace(kathete1 + " " + kathete2 + " " + hypothenuse + " ");
+
+    if (((kathete1 ^ 2) + (kathete2 ^ 2)) <= (hypothenuse ^ 2)) {
+      logger.trace("Collision");
+      return true;
+    }
+    return false;
+  }
+
+
+
+  @Override
+  public boolean collidesWith(Collider other) {
+
+    // circ circ
+    try {
+      return checkCollisionCircCirc(other);
+    } catch (Exception e) {
+    }
+
+    try {
+      return other.collidesWith(this);
+    } catch (Exception e) {
+    }
+
+    throw new RuntimeException("Collider type not implemented!");
+  }
+
+  private Color color = Color.WHITE;
+
+
+
+}
--- a/src/collider/Collider.java
+++ b/src/collider/Collider.java
@ -0,0 +1,127 @@
+package collider;
+
+import java.awt.Graphics2D;
+import java.util.LinkedList;
+import gameobjects.GameObject;
+import playground.Playground;
+import controller.ObjectController;
+
+/**
+ * abstract base class for all Colliders to detect collisions between GameObjects
+ * 
+ *
+ */
+public abstract class Collider {
+
+  /** unique internal name for Collider */
+  public String id = null;
+  /** GameObject it belongs to */
+  protected GameObject gameobject = null;
+  /** PlayGround instance it belongs to */
+  protected Playground playground = null;
+  /** the ObjectController to the corresponding GameObject (can be null) */
+  protected ObjectController controller = null;
+
+  protected double dx = 0.;
+  double dy = 0.;
+
+  /**
+   * 
+   * @param id unique name for Collider (internally)
+   * @param o GameObject instance it belongs to
+   */
+  public Collider(String id, GameObject o) {
+    this.gameobject = o;
+
+    this.id = id;
+    this.controller = o.getObjectController();
+    this.playground = o.getPlayground();
+
+  }
+
+
+  /**
+   * setter for offset values to be used relative to GameObject center. default is zero.
+   * 
+   * @param dx offset in X direction (default 0)
+   * @param dy offset in Y direction (default 0)
+   * @return this instance of Collider
+   */
+  public Collider setOffsets(double dx, double dy) {
+    this.dx = dx;
+    this.dy = dy;
+    return this;
+  }
+
+  public String toString() {
+    return "baseColl";
+  }
+
+  /**
+   * returns the corresponding game objects X coordinate (center) plus this colliders offset in X
+   * (probably zero).
+   * 
+   * @return X value
+   */
+  public double getX() {
+    return this.gameobject.getX() + this.dx;
+  }
+
+
+  /**
+   * returns the corresponding game objects Y coordinate (center) plus this colliders offset in Y
+   * (probably zero).
+   * 
+   * @return Y value
+   */
+  public double getY() {
+    return this.gameobject.getY() + this.dy;
+  }
+
+  /**
+   * returns the internal unique name
+   * 
+   * @return the String with the name
+   */
+  public String getId() {
+    return id;
+  }
+
+
+  /**
+   * setter for corresponding GameObject
+   * 
+   * @param gameObject to be saved in attribute
+   */
+  public void setObject(GameObject gameObject) {
+    this.gameobject = gameObject;
+  }
+
+  /**
+   * setter for GameController
+   * 
+   * @param controller to be saved in attribute
+   */
+  public void setController(ObjectController controller) {
+    this.controller = controller;
+  }
+
+  /**
+   * setter for Playground instance this collider belongs to
+   * 
+   * @param playground instance to be stored in attribute
+   */
+  public void setPlayground(Playground playground) {
+    this.playground = playground;
+  }
+
+  /**
+   * checks the collission with another collider instance.
+   * 
+   * @param other the instance to compare to
+   * @return true if the colliders collide (touch or overlap)
+   */
+  abstract public boolean collidesWith(Collider other);
+
+
+}
--- a/src/collider/RectCollider.java
+++ b/src/collider/RectCollider.java
@ -0,0 +1,127 @@
+package collider;
+
+import java.awt.Color;
+
+import gameobjects.*;
+import org.apache.logging.log4j.Logger;
+import org.apache.logging.log4j.LogManager;
+
+/** a {@link Collider} for Rectangles, usually used for {@link RectObject} instances.
+ * @see gameobjects.RectObject#generateColliders() 
+ */
+public class RectCollider extends Collider {
+
+  //double x;
+  //double y;
+  //double vx;
+  //double vy;
+  double w, h;
+
+  private Color color = Color.WHITE;
+  
+  private static Logger logger = LogManager.getLogger(RectCollider.class);
+
+  /**
+   * initializes this RectCollider.
+   * calls superclass constructor of {@link Collider#Collider(String, GameObject)} with params String id and GameObject o.
+   * 
+   * @param id String unique name for this RectCollider
+   * @param o GameObject instance this RectCollider belongs to (cannot be null)
+   * @param w width in pixels for the collider dimensions (> 0)
+   * @param h height in pixels for the collider dimensions (>0)
+   */
+  public RectCollider(String id, GameObject o, double w, double h) {
+    super(id, o);
+    this.w = w;
+    this.h = h;
+  }
+
+  public String toString() {
+    return " " + w + " " + h + " ";
+  }
+
+  /**
+   * checks collision with other Collider, which needs to be a RectCollider, too.
+   * @param other RectCollider (is casted) to calculate collision with
+   * @return true if collission is detected
+   */
+  public boolean checkCollisionRectRect(Collider other) {
+    RectCollider r1 = this;
+    RectCollider r2 = (RectCollider) other;
+
+    if ((((r1.getX() + r1.w / 2.) >= (r2.getX() - r2.w / 2.)) && ((r1.getX() + r1.w / 2.) <= (r2
+        .getX() + r2.w / 2.)))
+        || (((r2.getX() + r2.w / 2.) >= (r1.getX() - r1.w / 2.)) && ((r2.getX() + r2.w / 2.) <= (r1
+            .getX() + r1.w / 2.)))) {
+      if ((((r1.getY() + r1.h / 2.) >= (r2.getY() - r2.h / 2.)) && ((r1.getY() + r1.h / 2.) <= (r2
+          .getY() + r2.h / 2.)))
+          || (((r2.getY() + r2.h / 2.) >= (r1.getY() - r1.h / 2.)) && ((r2.getY() + r2.h / 2.) <= (r1
+              .getY() + r1.h / 2.)))) {
+        return true;
+      }
+    }
+    return false;
+  }
+
+ /**
+  * checks collision with other Collider, which needs to be a CircleCollider
+  * @param other CircleCollider (is casted) to calculate collision with
+  * @return true if collission is detected
+  */
+  public boolean checkCollisionRectCirc(Collider other) {
+    RectCollider r = this;
+    CircleCollider c = (CircleCollider) (other);
+    double circleDistX = Math.abs(c.getX()  - (r.getX()  ));
+    double circleDistY = Math.abs(c.getY()  - (r.getY() ) );
+
+    logger.trace("c.x:"+c.x+" "+"c.y:"+c.y+" "+"c.r:"+c.r+" "+"r.x:"+r.getX()+" "+"r.y:"+r.getY()+" "+"r.w:"+r.w+" "+"r.h:"+r.h+" "+"circleDistX:"+circleDistX+" "+"circleDistY:"+circleDistY);
+
+    if (circleDistX > (r.w / 2 + c.r))
+      return false;
+    if (circleDistY > (r.h / 2 + c.r))
+      return false;
+
+    if (circleDistX <= (r.w / 2)) {
+        logger.trace("Collision Rect with circle");
+      return true;
+    }
+    if (circleDistY <= (r.h / 2)) {
+      logger.trace("Collision Rect with circle (second)");
+      return true;
+    }
+
+    double cornerDistSqr = Math.pow(circleDistX - r.w / 2, 2) + Math.pow(circleDistY - r.h / 2, 2); // Satz
+                                                                                                    // des
+                                                                                                    // Pythagoras
+    return (cornerDistSqr <= c.r * c.r); // falls true zurueckgegeben: Kollision
+  }
+
+
+
+  @Override
+  public boolean collidesWith(Collider other) {
+
+    // rect circ
+    try {
+      return checkCollisionRectCirc(other);
+    } catch (Exception e) {
+      // do nothing
+    }
+
+    // rect rect
+    try {
+      return checkCollisionRectRect(other);
+    } catch (Exception e) {
+      // do nothing
+    }
+
+    try {
+      return other.collidesWith(this);
+    } catch (Exception e) {
+      // do nothing
+    }
+
+    throw new RuntimeException("Collider type not implemented!");
+  }
+
+}
--- a/src/controller/CollisionAwareEgoController.java
+++ b/src/controller/CollisionAwareEgoController.java
@ -0,0 +1,84 @@
+package controller;
+
+import playground.*;
+import gameobjects.*;
+import java.util.*;
+import java.awt.event.*;
+import java.io.File;
+
+
+/**
+ * An EgoController which cannot move through obstacle objects (is collission aware). Only respects
+ * GameObjects that have the String 'obstacle' in their name.
+ *
+ */
+public class CollisionAwareEgoController extends EgoController {
+
+  double savex, savey, savevx, savevy;
+  double lastSpaceAt = -1;
+  private File shot = null;
+
+
+  /**
+   * 
+   * @param egoRad radius of ego object to be used.
+   */
+  public CollisionAwareEgoController(double egoRad) {
+    super(egoRad);
+  }
+
+  /**
+   * 
+   * @param egoRad radius of ego object to be used.
+   * @param soundOnShot WAV file to be played on shot
+   */
+  public CollisionAwareEgoController(double egoRad, File soundOnShot) {
+    super(egoRad);
+    this.shot = soundOnShot;
+  }
+
+  public void saveDynamicState() {
+    this.savex = this.getX();
+    this.savey = this.getY();
+    this.savevx = this.getVX();
+    this.savevy = this.getVY();
+  }
+
+
+  public void restoreDynamicState() {
+    this.setX(savex);
+    this.setY(savey);
+    this.setVX(savevx);
+    this.setVY(savevy);
+  }
+
+
+  public boolean stopObject() {
+    boolean s = super.stopObject();
+
+    Playground pg = this.getPlayground();
+
+    LinkedList<GameObject> obstacles = pg.collectObjects("obstacle", false);
+
+    this.saveDynamicState();
+    this.applySpeedVector();
+
+    for (GameObject ob : obstacles) {
+      if (ob.collisionDetection(this.gameObject)) {
+        this.restoreDynamicState();
+        return true;
+      }
+    }
+    this.restoreDynamicState();
+    return s;
+  }
+
+  public void onSpace(KeyEvent e, GameObject ego) {
+    double cgt = ego.getGameTime();
+    if ((cgt - this.lastSpaceAt) > 0.1) {
+      super.onSpace(e, ego);
+      Music.music(this.shot);
+    }
+
+  }
+}
--- a/src/controller/EgoController.java
+++ b/src/controller/EgoController.java
@ -0,0 +1,216 @@
+package controller;
+
+import java.awt.Color;
+import java.awt.event.KeyEvent;
+import playground.*;
+import gameobjects.*;
+import java.util.*;
+import org.apache.logging.log4j.Logger;
+import org.apache.logging.log4j.LogManager;
+
+/**
+ * Controller using key events for up, down, left, right and space (shooting) to control the ego
+ * object behavior.
+ */
+public class EgoController extends ObjectController {
+  // either rad is zero or width/height is zero (guaranteed by constructors)
+  private double rad = 0;
+  private double width = 0;
+  private double height = 0;
+
+  private Integer pressedKey = null;
+  private Integer lastPressedKey = null;
+  private static Logger logger = LogManager.getLogger(EgoController.class);
+
+
+  /**
+   *  constructor that gives the ego controller a radius to stop the ego object when it reaches the level boundaries.
+   * @param egoRad radius to use as a boundary stop for level borders (usually use the same dimensions as your ego object)
+   */
+  public EgoController(double egoRad) {
+    this.rad = egoRad;
+  }
+  
+  /**
+   *  constructor that gives the ego controller a width and height to stop the ego object when it reaches the level boundaries.
+   * @param width width to use as a boundary stop for level borders (usually use the same dimensions as your ego object)
+   * @param height height to use as a boundary stop for level borders (usually use the same dimensions as your ego object)
+   */
+  public EgoController(double width, double height) {
+    this.width = width;
+    this.height = height;
+  }
+
+
+  public void onUp(KeyEvent kc, GameObject ego) {
+    ego.setVX(0.0);
+    ego.setVY(-SpaceInvadersLevel.EGOSPEED);
+  }
+
+  public void onDown(KeyEvent kc, GameObject ego) {
+    ego.setVX(0.0);
+    ego.setVY(SpaceInvadersLevel.EGOSPEED);
+  }
+
+  public void onLeft(KeyEvent kc, GameObject ego) {
+    ego.setVY(0.0);
+    ego.setVX(-SpaceInvadersLevel.EGOSPEED);
+  }
+
+  public void onRight(KeyEvent kc, GameObject ego) {
+    ego.setVY(0.0);
+    ego.setVX(SpaceInvadersLevel.EGOSPEED);
+  }
+
+  public void onStop(KeyEvent kc, GameObject ego) {
+    ego.setVY(0.0);
+    ego.setVX(0.0);
+    ego.setComponentProperty("controller", "setDummy", "NEW");
+    ego.setComponentProperty("controller", "setDummy2", "XXX");
+  }
+
+
+  /** checks the position and respects level boundaries and own radius or width/height set on constructor. 
+   * 
+   * @return true if the object reached the boundaries of the level, false otherwise
+   */
+  public boolean stopObject() {
+    // check whether ego object is at level boundaries
+    // can use radius (rad) and width or height in one check as either rad or width/height is zero.
+    int pgSizeX = this.getPlayground().getSizeX();
+    int pgSizeY = this.getPlayground().getSizeY();
+    double ts = this.getTimestep();
+    if (this.getX() + rad + (width/2d) + this.getVX() * ts >= pgSizeX
+        || this.getX() - rad - (width/2d) + this.getVX() * ts < 0) {
+      return true;
+    }
+    if (this.getY() + rad + (height/2d) + this.getVY() * ts >= pgSizeY
+        || this.getY() - rad - (height/2d) + this.getVY() * ts < 0) {
+      return true;
+    }
+    return false;
+
+  }
+
+
+  /** behavior for shooting on key space
+   * 
+   * @param e KeyEvent of the space key
+   * @param ego EgoObject instance (used to determine position of shot object's start)
+   */
+  public void onSpace(KeyEvent e, GameObject ego) {
+    pressedKey = lastPressedKey;
+    lastPressedKey = null;
+
+    // create unique name for object
+    // read Flag nextShot read (if not existing already it will be set)
+    // it will be updated by 1 and saved
+    Integer nextShot =
+        (Integer) this.getPlayground().getOrCreateLevelFlag("nextShot", Integer.valueOf(0));
+    String shotName = "simpleShot" + nextShot++;
+    this.getPlayground().setLevelFlag("nextShot", nextShot);
+
+    SimpleShotController simpleshot = new SimpleShotController();
+    GameObject ss = new RectObject(shotName, this.getPlayground(), ego.getX(), ego.getY(), 0,
+        -1. * SpaceInvadersLevel.SHOTSPEED, 4, 12, Color.CYAN).addController(simpleshot);
+    ss.generateColliders();
+    this.getPlayground().addObject(ss);
+  }
+
+
+  /**
+   * updates position based on key events (mouse currently ignored)
+   */
+  public void updateObject() {
+
+    logger.trace("Playground inst is"+this.getPlayground()) ;
+    Stack<KeyEvent> keyEvents = this.getPlayground().getKeyEvents();
+
+    GameObject ego = this.gameObject;
+
+    while (!keyEvents.isEmpty()) {
+
+      KeyEvent e = keyEvents.pop();
+      boolean pressed = false;
+      boolean released = true;
+      int kc = e.getKeyCode();
+
+      if (e.paramString().indexOf("PRESSED") >= 0) {
+        pressed = true;
+        released = false;
+      }
+
+      /**
+       * Generelle Idee: Wenn eine Taste gedrückt wird wird sie gespeichert. wenn die zuvor
+       * gespeicherte Taste wieder losgelassen wird stoppt das Ego-Objekt. Falls vor dem Loslassen
+       * eine andere Taste gedrückt wird, wird diese gespeichert und die alte vergessen. Dh das
+       * loslassen der alten Taste stoppt das Objekt nicht. Spezialfall: space, das loslassen von
+       * space stoppt das Objekt nicht!
+       */
+
+      if (pressed == true) {
+        lastPressedKey = pressedKey;
+        pressedKey = kc;
+      }
+
+      /**
+       * Nur eine losgelassene Taste die auch vorher gedrückt wurde stoppt das Objekt. Eine
+       * losgelassene Taste die nicht vorher gedrückt wurde bzw vergessen wurde stoppt das Objekt
+       * nicht
+       */
+      if (released == true) {
+        if (pressedKey != null) {
+          if (pressedKey.equals(kc)) {
+            ego.setVX(0);
+            ego.setVY(0);
+            pressedKey = null;
+          }
+        }
+        continue;
+      }
+
+      if (kc == KeyEvent.VK_LEFT) {
+        this.onLeft(e, ego);
+      }
+
+      if (kc == KeyEvent.VK_RIGHT) {
+        this.onRight(e, ego);
+      }
+
+      if (kc == KeyEvent.VK_UP) {
+        this.onUp(e, ego);
+      }
+
+      if (kc == KeyEvent.VK_DOWN) {
+        this.onDown(e, ego);
+      }
+
+      // stop
+      if (kc == KeyEvent.VK_Z) {
+        this.onStop(e, ego);
+
+      }
+
+
+      // shot
+      if (kc == KeyEvent.VK_SPACE) {
+        // space is not registered! Releasing space does not stop the egoobject
+        this.onSpace(e, ego);
+      }
+    }
+
+
+    boolean stop = this.stopObject();
+
+    if (stop) {
+      this.setVX(0);
+      this.setVY(0);
+    }
+
+    // updateSpeed and position
+    applySpeedVector();
+
+  }
+
+
+}
--- a/src/controller/EnemyController.java
+++ b/src/controller/EnemyController.java
@ -0,0 +1,36 @@
+package controller;
+
+
+import org.apache.logging.log4j.Logger;
+import org.apache.logging.log4j.LogManager;
+
+/**
+ * This class controls the space invaders.
+ */
+public class EnemyController extends ObjectController {
+
+  private static Logger logger = LogManager.getLogger(EnemyController.class);
+
+  @Override
+  public void updateObject() {
+    logger.trace("updatre" + gameObject.getId());
+    if ((gameObject.getX() > this.getPlayground().getSizeX() * 0.9) && (gameObject.getVX() > 0)) {
+      logger.trace("toleft!" + gameObject.getX());
+      gameObject.setVX(-this.getVX());
+    }
+    if ((gameObject.getX() < this.getPlayground().getSizeX() * 0.1) && (gameObject.getVX() < 0)) {
+      logger.trace("toright!" + gameObject.getX());
+      gameObject.setVX(-this.getVX());
+    }
+
+    // if it reaches the bottom, delete it and deduct points
+    if (gameObject.getY() >= this.getPlayground().getSizeY()) {
+      this.getPlayground().deleteObject(gameObject.getId());
+      // add to points counter
+      Integer pts = (Integer) this.getPlayground().getGlobalFlag("points");
+      this.getPlayground().setGlobalFlag("points", pts - 200);
+    }
+
+    applySpeedVector();
+  }
+}
--- a/src/controller/FallingStarController.java
+++ b/src/controller/FallingStarController.java
@ -0,0 +1,24 @@
+package controller;
+
+import org.apache.logging.log4j.Logger;
+import org.apache.logging.log4j.LogManager;
+
+
+/**
+ * Controls background stars. When they touch the bottom of the display they reappear on top.
+ */
+public class FallingStarController extends ObjectController {
+  int rad = 3;
+  private static Logger logger = LogManager.getLogger(FallingStarController.class);
+
+
+  @Override
+  public void updateObject() {
+    logger.trace(
+        "+" + this.gameObject.getId() + " HO " + this.gameObject + "/" + this.getPlayground());
+    if (this.getY() + rad >= this.getPlayground().getSizeY()) {
+      this.setY(10);
+    }
+    applySpeedVector();
+  }
+}
--- a/src/controller/LimitedTimeController.java
+++ b/src/controller/LimitedTimeController.java
@ -0,0 +1,36 @@
+package controller;
+
+/**
+ * Controls and abject that is deleted after a lifetime specified in the constructor, and when it
+ * leaves the display.
+ */
+public class LimitedTimeController extends ObjectController {
+  int rad = 3;
+  double g0 = -1;
+  double duration = 0;
+
+  /**
+   * Constructor.
+   * 
+   * @param g0 int initial game time at creation
+   * @param duration int duration in seconds
+   */
+  public LimitedTimeController(double g0, double duration) {
+    this.g0 = g0;
+    this.duration = duration;
+  }
+
+  @Override
+  public void updateObject() {
+    double gameTime = this.getPlayground().getGameTime();
+    applySpeedVector();
+
+    if (gameObject.getY() >= getPlayground().getSizeY() || gameObject.getY() < 0
+        || gameObject.getX() >= getPlayground().getSizeX() || gameObject.getX() < 0
+        || (gameTime - g0) > duration) {
+
+      this.getPlayground().deleteObject(this.gameObject.getId());
+    }
+  }
+
+}
--- a/src/controller/MineController.java
+++ b/src/controller/MineController.java
@ -0,0 +1,47 @@
+package controller;
+
+import controller.ObjectController;
+import gameobjects.GameObject;
+
+import org.apache.logging.log4j.Logger;
+import org.apache.logging.log4j.LogManager;
+
+public class MineController extends ObjectController {
+  int rad = 3;
+
+  double xSpeed = 0.;
+  double lineSpeed = 0;
+  private static Logger logger = LogManager.getLogger(MineController.class);
+
+
+  public MineController(double lineSpeed) {
+    this.lineSpeed = lineSpeed;
+  }
+
+  @Override
+  public void updateObject() {
+
+    if (gameObject.getY() >= this.getPlayground().getSizeY() - 10) {
+      this.gameObject.setVY(0);
+      if (xSpeed == 0.) {
+        GameObject ego = getPlayground().getObject("ego");
+        double egoXPos = ego.getX();
+        if (egoXPos > this.gameObject.getX()) {
+          xSpeed = 50;
+        } else {
+          xSpeed = -50;
+        }
+        this.gameObject.setVX(xSpeed);
+
+      }
+      this.gameObject.setVX(xSpeed);
+
+    }
+    if (this.gameObject.getX() < 0 || (this.gameObject.getX() > this.getPlayground().getSizeX())) {
+      logger.debug("deleting" + this.gameObject.getId());
+      getPlayground().deleteObject(this.gameObject.getId());
+    }
+
+    applySpeedVector();
+  }
+}
--- a/src/controller/ObjectController.java
+++ b/src/controller/ObjectController.java
@ -0,0 +1,110 @@
+package controller;
+
+import gameobjects.GameObject;
+import playground.Playground;
+import org.apache.logging.log4j.Logger;
+import org.apache.logging.log4j.LogManager;
+
+/**
+ * Class that controls the LOGICAL behavior of an object independently of how it is displayed or
+ * drawn. The most important method here is {@link #updateObject}: this method is, by various
+ * indirections, called exactly once per game time step for every object that is on the playground.
+ * It has, by virtue of the member variables {@link #gameObject} full access to
+ * <ul>
+ * <li>the object it is controlling
+ * <li>the playground this object belongs to
+ * </ul>
+ * Typically, updateObject would check whether an object leaves the screen to react appropriately.
+ * In that case the object can be marked for deletion (by adding it to the flag "deleted" that is
+ * always defined for any playground), but of course other reactions are possible like rebounding,
+ * emerging on the other side, ...
+ */
+
+public abstract class ObjectController {
+  protected GameObject gameObject = null;
+  protected String dummy = "";
+  
+  private static Logger logger = LogManager.getLogger(ObjectController.class); 
+
+  public void setObject(GameObject gameObject) {
+    this.gameObject = gameObject;
+  }
+
+
+  public void setDummy(String x) {
+    logger.debug("DUMMY called!!");
+    this.dummy = x;
+    logger.debug("DUMMY is now:" + dummy);
+  }
+
+  /**
+   * Is called once every game time step by the game itself. NEVER call this directly, not
+   * necessary!<br>
+   * The method can do whatever it likes, including nothing. The attribute {@link #gameObject}
+   * contains a reference to the controlled object, which allows access to the Playground the object
+   * belongs to (useful for getting the pixel size in x and y of the playing field.<br>
+   * <strong>Recommended:</strong> when implementing this method, call at the end
+   * {@link #applySpeedVector() } method. This is a helper method that sets the new x,y coordinates
+   * for the {@link #gameObject} correctly.
+   */
+  public abstract void updateObject();
+
+  /**
+   * Convenience method: simply moves the object forward one step from its present position, using
+   * its present speed.
+   */
+  public void applySpeedVector() {
+    double ts = this.getPlayground().getTimestep();
+    this.setX(this.getX() + this.getVX() * ts);
+    gameObject.setY(this.getY() + this.getVY() * ts);
+  }
+
+
+  public double getTimestep() {
+    return this.gameObject.getPlayground().getTimestep();
+  }
+
+  public double getX() {
+    return this.gameObject.getX();
+  }
+
+  public double getY() {
+    return this.gameObject.getY();
+  }
+
+  public double getVX() {
+    return this.gameObject.getVX();
+  }
+
+  public double getVY() {
+    return this.gameObject.getVY();
+  }
+
+  public void setX(double x) {
+    this.gameObject.setX(x);
+  }
+
+
+  public void setY(double y) {
+    this.gameObject.setY(y);
+  }
+
+  public void setVX(double vx) {
+    this.gameObject.setVX(vx);
+  }
+
+  public void setVY(double vy) {
+    this.gameObject.setVY(vy);
+  }
+
+  public Playground getPlayground() {
+    return this.gameObject.getPlayground();
+  }
+
+  public void setPlayground(Playground playground) {
+    this.gameObject.setPlayground(playground);
+  }
+
+
+
+}
--- a/src/controller/SimpleShotController.java
+++ b/src/controller/SimpleShotController.java
@ -0,0 +1,16 @@
+package controller;
+
+public class SimpleShotController extends ObjectController {
+  int rad = 3;
+
+  @Override
+  public void updateObject() {
+    if (gameObject.getY() < 0) {
+      // LinkedList<String> deleteList = (LinkedList<String>) playground.getFlag("delete");
+      // deleteList.add(gameObject.getId());
+      getPlayground().deleteObject(this.gameObject.getId());
+    } else {
+      applySpeedVector();
+    }
+  }
+}
--- a/src/controller/ZickZackController.java
+++ b/src/controller/ZickZackController.java
@ -0,0 +1,32 @@
+package controller;
+
+import org.apache.logging.log4j.Logger;
+import org.apache.logging.log4j.LogManager;
+
+public class ZickZackController extends EnemyController {
+  protected double g0;
+  protected double dt;
+  protected double lastMod = -1;
+
+  private static Logger logger = LogManager.getLogger(ZickZackController.class);
+  
+  public ZickZackController(double gameTime, double dt) {
+    super();
+    this.dt = dt;
+    this.g0 = gameTime;
+  }
+
+  public void updateObject() {
+    double gameTime = this.getPlayground().getGameTime();
+    logger.trace("current Object x: "+gameObject.getX());
+    double mod = (gameTime - this.g0) % this.dt;
+    if (mod < lastMod) {
+      gameObject.setVX(-1.0 * gameObject.getVX());
+      logger.trace("inverting VX");
+    }
+    lastMod = mod;
+
+    super.updateObject();
+
+  }
+}
--- a/src/controller/package-info.java
+++ b/src/controller/package-info.java
@ -0,0 +1,11 @@
+/**
+ * The controller package contains Object controllers that govern an objects behavior, without being
+ * involved in its collision or drawing properties. Object controllers react to user actions/inputs
+ * and govern for example the movement of {@link gameobjects.GameObject} instances. They can access
+ * their parent objects' properties and, by indirection, the properties and methods of the
+ * associated level. <br>
+ * Controllers should be designed in such a way that they implement behavior that is
+ * level-independent. All level-dependent behavior should be implemented in
+ * {@link playground.Playground#applyGameLogic}.
+ */
+package controller;
--- a/src/gameobjects/AnimatedGameobject.java
+++ b/src/gameobjects/AnimatedGameobject.java
@ -0,0 +1,42 @@
+package gameobjects;
+
+import java.util.LinkedList;
+import playground.Playground;
+import playground.Animation;
+import collider.Collider;
+import collider.RectCollider;
+import rendering.*;
+import org.apache.logging.log4j.Logger;
+import org.apache.logging.log4j.LogManager;
+
+
+public class AnimatedGameobject extends GameObject {
+
+  protected AnimationArtist animArtist;
+  private static Logger logger = LogManager.getLogger(AnimationArtist.class);
+
+
+  // auto-generates collider according to box width/height
+  public GameObject generateColliders() {
+    logger.debug("Created animated Obj "+ this.animArtist.getW()+" "+this.animArtist.getH()) ;
+    double w = this.animArtist.getW() ;
+    double h = this.animArtist.getH() ;
+    this.addCollider(new RectCollider("RectColl_" + this.id, this, w,
+        h)) ;
+        
+    logger.info("ANIMGO-COLL ID="+this.getId()+" WH= "+w+"/"+h) ;
+    return this ;
+  }
+
+
+  public AnimatedGameobject(String id, Playground pg, double x, double y, double vx, double vy,
+      double scale, Animation anim, double t0, String abspielmodus) {
+    super(id, pg, x, y, vx, vy); // Konstruktor-Aufruf GameObject
+
+    this.artist = new AnimationArtist(this, anim, t0, abspielmodus, scale);
+    this.animArtist = (AnimationArtist) (this.artist);
+
+  }
+
+
+}
--- a/src/gameobjects/EgoObject.java
+++ b/src/gameobjects/EgoObject.java
@ -0,0 +1,34 @@
+package gameobjects;
+
+
+import java.awt.Color;
+import collider.*;
+import java.awt.Graphics2D;
+import java.awt.image.BufferedImage;
+import java.io.File;
+import java.io.IOException;
+import java.util.LinkedList;
+import javax.imageio.ImageIO;
+import collider.Collider;
+import controller.ObjectController;
+import playground.Playground;
+import rendering.*;
+
+public class EgoObject extends GameObject {
+
+  double egoRad = 0;
+
+  public EgoObject(String id, Playground pg, double x, double y, double vx, double vy,
+      double egoRad) {
+    super(id, pg, x, y, vx, vy);
+    this.egoRad = egoRad;
+    this.artist = new CircleArtist(this, egoRad, Color.WHITE);
+  }
+
+  public GameObject generateColliders() {
+    CircleCollider coll = new CircleCollider("coll", this, this.egoRad);
+    this.addCollider(coll);
+    return this;
+  }
+
+}
--- a/src/gameobjects/FallingStar.java
+++ b/src/gameobjects/FallingStar.java
@ -0,0 +1,28 @@
+package gameobjects;
+
+import java.awt.Color;
+import java.util.LinkedList;
+import collider.*;
+import playground.Playground;
+import rendering.*;
+
+public class FallingStar extends GameObject {
+
+  private Color color = Color.WHITE;
+
+  protected double rad = -1;
+
+
+  public FallingStar(String id, Playground playground, double x, double y, double vx, double vy,
+      Color color, double rad) {
+    super(id, playground, x, y, vx, vy);
+    this.rad = rad;
+    this.color = color;
+    LinkedList<Collider> cols = new LinkedList<Collider>();
+    CircleCollider cc = new CircleCollider("cc", this, rad);
+    cols.add(cc);
+    setColliders(cols);
+    this.artist = new CircleArtist(this, rad, color);
+  }
+
+}
--- a/src/gameobjects/GameObject.java
+++ b/src/gameobjects/GameObject.java
@ -0,0 +1,377 @@
+package gameobjects;
+
+import java.awt.Graphics2D;
+import java.awt.image.BufferedImage;
+import java.util.LinkedList;
+import java.lang.reflect.*;
+import rendering.*;
+import collider.Collider;
+import controller.ObjectController;
+import playground.Playground;
+import org.apache.logging.log4j.Logger;
+import org.apache.logging.log4j.LogManager;
+
+/**
+ * The class {@link GameObject} represents a (possibly animated) object appearing in a level of the
+ * game. It is therefore attached to an instance of the class {@link Playground}. A GameObject has
+ * at least the following properties:
+ * <ul>
+ * <li>2D screen position
+ * <li>2D speed
+ * <li>a name that is unique within a certain {@link Playground}<br>
+ * <li>a reference to the {@link Playground} object it belongs to<br>
+ * <li>a reference to an instance of {@link controller.ObjectController} that handles the movement
+ * logic of the object<br>
+ * <li>a (circular) radius for simple collision checking. This may be handled differently in
+ * subclasses<br>
+ * </ul>
+ * The main task of GameObject, or its subclasses, is to draw the object on the screen, which is
+ * handles by the {@link #draw(Graphics2D)} method. It is this method that must be redefined if a
+ * new appearance should be realized. For introducing new behavior, it is sufficient to supply a
+ * different {@link controller.ObjectController} instance when constructing a GameObject.
+ */
+public abstract class GameObject {
+
+  public static final int RADIUS = 0;
+  public static final int RECTANGLE = 1;
+  public static final int MASK = 2;
+
+  protected Artist artist = null;
+
+  public String id = null;
+  protected double x = 0;
+  protected double vx = 0;
+  protected double y = 0;
+  protected double vy = 0;
+  protected BufferedImage mask = null; // UNDONE implement usage of mask
+  protected boolean active = true;
+  // public int collisionMode = GameObject.RADIUS;
+  protected Playground playground = null;
+
+  private ObjectController controller = null;
+  public LinkedList<Collider> scol;
+
+  private static Logger logger = LogManager.getLogger(GameObject.class);
+
+  /**
+   * Constructor to initialize a GameObject, respectively set the current {@link Playground}
+   * instance this GameObject belongs to.
+   * 
+   * @param id unique ID for this GameObject (should not be null or empty String)
+   * @param playground the Playground the GameObject belongs to (should not be null)
+   * @param x initial screen position in direction horizontal (positive value including zero)
+   * @param y initial screen position in direction vertical (positive value including zero)
+   * @param vx initial speed (velocity) in direction horizontal (can be negative, zero, positive)
+   * @param vy initial speed (velocity) in direction horizontal (can be negative, zero, positive)
+   */
+  public GameObject(String id, Playground playground, double x, double y, double vx, double vy) {
+    setX(x);
+    setY(y);
+    setVX(vx);
+    setVY(vy);
+    this.id = id;
+    this.controller = null;
+    this.scol = new LinkedList<Collider>();
+    this.setPlayground(playground);
+  }
+
+  /**
+   * Constructor to initialize a GameObject, respectively set the current Playground instance this
+   * GameObject belongs to.
+   * 
+   * @param id unique ID for this GameObject (should not be null or empty String)
+   * @param playground the Playground the GameObject belongs to (should not be null)
+   * @param controller controller instance to be used for this GameObject (can be null)
+   * @param x initial screen position in direction horizontal (positive value including zero)
+   * @param y initial screen position in direction vertical (positive value including zero)
+   * @param vx initial speed (velocity) in direction horizontal (can be negative, zero, positive)
+   * @param vy initial speed (velocity) in direction horizontal (can be negative, zero, positive)
+   */
+  public GameObject(String id, Playground playground, ObjectController controller, double x,
+      double y, double vx, double vy) {
+    this(id, playground, x, y, vx, vy);
+    this.controller = controller;
+    if (this.controller != null) {
+      this.controller.setObject(this);
+      this.controller.setPlayground(playground);
+    }
+  }
+
+  /**
+   * sets colliders.
+   * 
+   * @param l LinkedList of Colliders.
+   */
+  public void setColliders(LinkedList<Collider> l) {
+    this.scol = l;
+  }
+
+  /**
+   * generates and sets collider(s) for this GameObject. This implementation does nothing. Intended
+   * to be overridden by subclasses.
+   * 
+   * @return instance of this GameObject (this).
+   */
+  public GameObject generateColliders() {
+    return this;
+  }
+
+  /**
+   * Sets the controller to use for this GameObject's logical behavior.
+   * 
+   * @param c instance to be used.
+   * @return the current instance (this).
+   */
+  public GameObject addController(ObjectController c) {
+    this.controller = c;
+    this.controller.setObject(this);
+    this.controller.setPlayground(playground);
+    return this;
+  }
+
+  /**
+   * Sets the artist to be used for drawing the object onto visible canvas area.
+   * 
+   * @param a instance to be used for calling {@link rendering.Artist#draw(Graphics2D)}.
+   * @return the current instance (this).
+   */
+  public GameObject addArtist(Artist a) {
+    this.artist = a;
+    return this;
+  }
+
+  /**
+   * saves the collider in the internal list of Colliders to be used for this GameObject.
+   * 
+   * @param c instance to be added to internal list
+   */
+  public void addCollider(Collider c) {
+    if (this.scol == null) {
+      this.scol = new LinkedList<Collider>();
+    }
+    this.scol.add(c);
+  }
+
+  public Playground getPlayground() {
+    return playground;
+  }
+
+  public void setPlayground(Playground playground) {
+    this.playground = playground;
+  }
+
+  /**
+   * calls via reflection a method of a component if this GameObjects instance and provides the
+   * given value as String parameter.
+   * 
+   * @param comp class name of GameObject component. Currently only "controller" is supported,
+   *        otherwise nothing happens.
+   * @param property method name of the component to call.
+   * @param value argument to pass to the method as String parameter.
+   */
+  public void setComponentProperty(String comp, String property, Object value) {
+    if (comp.equals("controller")) {
+      Class<? extends Object> clO = this.controller.getClass();
+      for (Method m : clO.getMethods()) {
+        if (m.getName().indexOf(property) != -1) {
+          logger.debug("Method " + property + " found!!");
+          try {
+            m.invoke(this.getObjectController(), value);
+          } catch (Exception e) {
+          }
+        }
+      }
+
+    }
+  }
+
+  public void setObjectFlag(String flag, Object value) {
+    this.playground.setLevelFlag(this.id + "/" + flag, value);
+  }
+
+
+  public Object getObjectFlag(String flag) {
+    return this.playground.getLevelFlag(this.id + "/" + flag);
+  }
+
+
+  public Object getOrCreateObjectFlag(String flag, Object createValue) {
+    return this.playground.getOrCreateLevelFlag(this.id + "/" + flag, createValue);
+  }
+
+
+
+  public boolean isActive() {
+    return active;
+  }
+
+
+  public GameObject setActive(boolean flag) {
+    this.active = flag;
+    return this;
+  }
+
+  /**
+   * return the unique object ID.
+   * 
+   * @return unique object ID
+   */
+  public String getId() {
+    return id;
+  }
+
+  /**
+   * gets the screen X position.
+   * 
+   * @return screen x position
+   */
+  public double getX() {
+    return x;
+  }
+
+  /**
+   * gets the screen Y position.
+   * 
+   * @return screen Y position
+   */
+  public double getY() {
+    return y;
+  }
+
+  /**
+   * gets the screen X speed in pixels per frame.
+   * 
+   * @return screen x speed
+   */
+  public double getVX() {
+    return vx;
+  }
+
+  /**
+   * gets the screen Y speed in pixels per frame.
+   * 
+   * @return screen y speed
+   */
+  public double getVY() {
+    return vy;
+  }
+
+  /**
+   * set screen x position.
+   * 
+   * @param x new position
+   */
+  public void setX(double x) {
+    if (this.active == true) {
+      this.x = x;
+    }
+  }
+
+  /**
+   * set screen y position.
+   * 
+   * @param y new position
+   */
+  public void setY(double y) {
+    if (this.active == true) {
+      this.y = y;
+    }
+  }
+
+  /**
+   * set screen x speed in pixel per frame
+   * 
+   * @param vx new x speed
+   */
+  public void setVX(double vx) {
+    if (this.active == true) {
+      this.vx = vx;
+    }
+  }
+
+  /**
+   * set screen y speed in pixel per frame.
+   * 
+   * @param vy new y speed.
+   */
+  public void setVY(double vy) {
+    if (this.active == true) {
+      this.vy = vy;
+    }
+  }
+
+  /**
+   * Sets a new object controller (replaces any former one).
+   * 
+   * @param controller An instance of {@link controller.ObjectController} or one of its subclasses.
+   */
+  public void setObjectController(ObjectController controller) {
+    this.controller = controller;
+  }
+
+
+  /**
+   * Access to object controller.
+   * 
+   * @return the controller for this object.
+   */
+  public ObjectController getObjectController() {
+    return this.controller;
+  }
+
+
+  public double getGameTime() {
+    return this.playground.getGameTime();
+  }
+
+
+
+  /**
+   * Collision detection implemented by iteration through the own list of {@link collider.Collider}
+   * and calling their {@link collider.Collider#collidesWith(Collider)} method to check collision
+   * with the given parameter instance of other {@link GameObject}.
+   * 
+   * @param other instance of the other GameObject to check collision with
+   * @return true if collision is detected, false otherwise
+   */
+  public boolean collisionDetection(GameObject other) {
+    if (this.scol == null) {
+      return false;
+    }
+    for (Collider c : this.scol) {
+      logger.trace(other.id);
+      for (Collider o : other.scol) {
+        if (c.collidesWith(o)) {
+          logger.trace(c.id + " " + o.id);
+          return true;
+        }
+      }
+    }
+    return false;
+
+  }
+
+  /**
+   * triggers this GameObjects own controller (if set) to update the object.
+   * 
+   * @see GameObject#controller
+   */
+  public void updateObject() {
+    if (this.controller != null) {
+      controller.updateObject();
+    }
+  }
+
+  /**
+   * Draws the object in its current state. Is called by the game engine, should NOT be called
+   * otherwise.
+   * 
+   * @param g object that has all the necessary drawing functionalities
+   */
+  public void draw(Graphics2D g) {
+    if (this.artist != null) {
+      this.artist.draw(g);
+    }
+  }
+
+}
--- a/src/gameobjects/RectObject.java
+++ b/src/gameobjects/RectObject.java
@ -0,0 +1,76 @@
+package gameobjects;
+
+import java.awt.Color;
+import java.io.File;
+import collider.RectCollider;
+import playground.Playground;
+import playground.SpaceInvadersLevel;
+import rendering.RectArtist;
+
+/**
+ * A rectangle object. <br>
+ * If {@link #generateColliders()} is called, it generates a RectCollider with id-prefix
+ * "shotcollider_" and registers it for this RectObject.
+ *
+ */
+public class RectObject extends GameObject {
+
+  /** width in pixels of the RectObject (&gt; 0) */
+  protected double width;
+  /** height in pixels of the RectObject (&gt; 0) */
+  protected double height;
+
+  /**
+   * Initializes the RectObject with a suitable RectArtist for drawing the RectObject.
+   * 
+   * @param id String unique name to be used.
+   * @param pg {@link Playground} instance this RectObject belongs to (the level it belongs to).
+   * @param x position in horizontal direction in pixels (zero or positive number).
+   * @param y position in vertical direction in pixels (zero or positive number).
+   * @param vx speed/velocity in horizontal direction in pixels (negative, zero or positive number).
+   * @param vy speed/velocity in vertical direction in pixels (negative, zero or positive number).
+   * @param width in pixels
+   * @param height in pixels
+   * @param color solid color for the whole object, used to initialize an instance of
+   *        {@link rendering.RectArtist} used for this RectObject.
+   */
+  public RectObject(String id, Playground pg, double x, double y, double vx, double vy,
+      double width, double height, Color color) {
+    super(id, pg, x, y, vx, vy);
+
+    this.width = width;
+    this.height = height;
+
+    this.artist = new RectArtist(this, width, height, color);
+
+  }
+
+
+  /**
+   * generates a new {@link RectCollider} with id-prefix "shotcollider_" and registers it for 'this'
+   * [@link RectObject}. The {@link RectCollider} uses the same dimensions ({@link #width} and {@link #height}) as this RectObject.
+   * 
+   * @return this RectObject itself
+   */
+  public RectObject generateColliders() {
+    this.scol.add(new RectCollider("shotcollider_" + id, this, this.width, this.height));
+    return this;
+  }
+  
+  /** Getter for the width
+   * 
+   * @return double width value as set by constructor
+   */
+  public double getWidth() {
+    return this.width;
+  }
+  
+  /** Getter for the height
+   * 
+   * @return double height value as set by constructor
+   */
+  public double getHeight() {
+    return this.height;
+  }
+
+}
--- a/src/gameobjects/TextObject.java
+++ b/src/gameobjects/TextObject.java
@ -0,0 +1,70 @@
+package gameobjects;
+
+import java.awt.Color;
+import java.awt.Font;
+import java.awt.Graphics2D;
+import java.awt.font.FontRenderContext;
+import java.awt.font.TextAttribute;
+import java.text.AttributedString;
+import java.util.LinkedList;
+import collider.*;
+import controller.ObjectController;
+import playground.Playground;
+import rendering.*;
+
+/**
+ * Convenience Class subclassing {@link GameObject}, directly instanciating {@link TextArtist} a
+ * subclass of {@link Artist} that draws a text. The controller is left undefined, the collider as
+ * well. However, a single call to the overwritten method {@link #generateColliders} will in fact
+ * generate a {@link RectCollider} of just the right size for the text.
+ *
+ */
+public class TextObject extends GameObject {
+
+  private String text = null;
+  protected double rx, ry;
+
+  public String getText() {
+    return this.text;
+  }
+
+  /**
+   * Constructor.
+   * 
+   * @param id object name
+   * @param playground containing {@link Playground} instance
+   * @param x positionx
+   * @param y positiony
+   * @param vx speedx
+   * @param vy speedy
+   * @param size font size in Pixel
+   * @param text String to be displayed
+   * @param textColor text color, see java.awt.Color
+   */
+  public TextObject(String id, Playground playground, double x, double y, double vx, double vy,
+      String text, int size, Color textColor) {
+    super(id, playground, x, y, vx, vy);
+
+    this.artist = new TextArtist(this, text, size, textColor);
+
+    this.setColliders(new LinkedList<Collider>());
+
+  }
+
+
+  public void setText(String s) {
+    this.text = s;
+    ((TextArtist) this.artist).setText(s);
+  }
+
+  public TextObject generateColliders() {
+    // we need to Cast to TextArtist as we want to access Width and Height of text
+    TextArtist kruecke = (TextArtist) (this.artist);
+
+    this.scol.clear();
+    this.scol.add(new RectCollider("rect", this, kruecke.getTextWidth(), kruecke.getTextHeight()));
+    return this;
+  }
+
+
+}
--- a/src/log4j2.xml
+++ b/src/log4j2.xml
@ -0,0 +1,30 @@
+<?xml version="1.0" encoding="UTF-8"?>
+
+<configuration status="OFF">
+	<appenders>
+		
+		<Console name="Console" target="SYSTEM_OUT">
+			<PatternLayout pattern="%d %-5level %logger{36} - %msg%n" />
+		</Console>
+		
+		<File name="File" fileName="log\log4j.log">
+			<PatternLayout pattern="%d %-5level %logger{36} - %msg%n" />
+		</File>
+		
+	</appenders>
+	
+	<loggers>
+	
+		<root level="warn">
+			<appender-ref ref="Console" />
+			<appender-ref ref="File" />
+		</root>
+		
+		<Logger name="base.GameLoop" level="info">      		
+    	</Logger>
+    	
+    	<Logger name="playground" level="info">      		
+    	</Logger>
+		
+	</loggers>
+</configuration>
--- a/src/playground/Animation.java
+++ b/src/playground/Animation.java
@ -0,0 +1,84 @@
+package playground;
+
+
+import java.awt.image.BufferedImage;
+
+import javax.imageio.ImageIO;
+import java.io.File;
+import java.io.*;
+import java.io.FileNotFoundException;
+import java.util.LinkedList;
+import java.util.Locale;
+import java.util.Scanner;
+import java.nio.file.Path;
+import java.nio.file.Paths;
+
+import org.apache.logging.log4j.Logger;
+import org.apache.logging.log4j.LogManager;
+
+public class Animation {
+
+  public LinkedList<String> fileList = null;
+  public LinkedList<Double> showtimeList = null;
+  public LinkedList<BufferedImage> imageList = null;
+
+  private static Logger logger = LogManager.getLogger(Animation.class);
+
+  public Animation(String datName) {
+
+    Scanner scanner;
+    this.fileList = new LinkedList<String>();
+    this.showtimeList = new LinkedList<Double>();
+    this.imageList = new LinkedList<BufferedImage>();
+
+    try {
+      scanner = new Scanner(new File(datName), "UTF-8");
+
+      scanner.useLocale(Locale.GERMANY);
+
+      String zeile;
+      double zeit;
+      int it = 0;
+
+      while (scanner.hasNext()) {
+        if (scanner.hasNextDouble()) {
+          zeit = scanner.nextDouble();
+          showtimeList.add(zeit);
+        } else {
+          zeile = scanner.next();
+          Path basePath = Paths.get(datName);
+          String file = basePath.getParent().toString() + "/" + zeile;
+          fileList.add(file);
+          try {
+            this.imageList.add(ImageIO.read(new File(file)));
+            logger.info("img added " + file);
+
+          } catch (IOException e) {
+            logger.warn(file + " not found!!");
+          }
+
+          it++;
+          logger.trace(basePath.getParent().toString() + "/" + zeile);
+        }
+      }
+
+      scanner.close();
+
+    } catch (FileNotFoundException e) {
+      e.printStackTrace();
+    }
+  }
+
+  public LinkedList<String> getFileList() {
+    return this.fileList;
+  }
+
+  public LinkedList<Double> getShowtimeList() {
+    return this.showtimeList;
+  }
+
+  public LinkedList<BufferedImage> getImageList() {
+    return this.imageList;
+  }
+
+}
--- a/src/playground/HighscoreManager.java
+++ b/src/playground/HighscoreManager.java
@ -0,0 +1,55 @@
+package playground;
+
+import java.io.*;
+import java.util.Scanner;
+
+import org.apache.logging.log4j.Logger;
+import org.apache.logging.log4j.LogManager;
+
+
+// Klasse um Highscore umzusetzen
+public class HighscoreManager {
+  Scanner s;
+  private static Logger logger = LogManager.getLogger(HighscoreManager.class);
+
+  public HighscoreManager() {
+    try {
+      File f = new File("./highscore.txt");
+      if (!f.exists()) {
+        logger.warn("WARNING: Highscore file was not found and reset");
+        writeHSToFile(0, -1);
+      }
+      s = new Scanner(f);
+    } catch (FileNotFoundException e) {
+      e.printStackTrace();
+    }
+  }
+
+  public int readHSFromFile() {
+    if (s.hasNext()) {
+      int highscore = s.nextInt();
+      return highscore;
+    }
+    return 0;
+  }
+
+  public static void writeHSToFile(Integer pts, Integer highscore) {
+    String highscore2 = String.valueOf(pts);
+    BufferedWriter bw;
+    try {
+      if (pts > highscore) {
+        FileWriter fw = new FileWriter("./highscore.txt");
+        bw = new BufferedWriter(fw);
+        bw.write(highscore2);
+        bw.close();
+        logger.info("Highscore file was opened and saved score: " + highscore2);
+      }
+    } catch (IOException e) {
+      logger.error("File for Highscore not writeable! Score lost.");
+    }
+  }
+
+  public void closeFile() {
+    s.close();
+  }
+}
--- a/src/playground/Level1.java
+++ b/src/playground/Level1.java
@ -0,0 +1,15 @@
+package playground;
+
+
+/**
+ * extends {@link SpaceInvadersLevel} with a boring start message
+ */
+public class Level1 extends SpaceInvadersLevel {
+
+  @Override
+  protected String getStartupMessage() {
+    return "Get ready for boring level 1!";
+  }
+
+
+}
--- a/src/playground/Level2.java
+++ b/src/playground/Level2.java
@ -0,0 +1,17 @@
+package playground;
+
+
+
+/**
+ * extends extends {@link SpaceInvadersLevel} with a different startup message.
+ */
+public class Level2 extends SpaceInvadersLevel {
+
+  @Override
+  protected String getStartupMessage() {
+    return "Get ready for level 2!";
+  }
+
+
+
+}
--- a/src/playground/Level3.java
+++ b/src/playground/Level3.java
@ -0,0 +1,40 @@
+package playground;
+
+import org.apache.logging.log4j.LogManager;
+import org.apache.logging.log4j.Logger;
+import controller.ObjectController;
+import controller.ZickZackController;
+import gameobjects.AnimatedGameobject;
+import gameobjects.GameObject;
+
+
+/**
+ * extends {@link SpaceInvadersLevel} with a ZigZack move of the enemies in
+ * {@link #createSingleEnemy(String, double, double, double, double, ObjectController, double)} and
+ * sets a different {@link #getStartupMessage()}.
+ */
+public class Level3 extends SpaceInvadersLevel {
+
+  private static Logger logger = LogManager.getLogger(Level3.class);
+
+  @Override
+  protected String getStartupMessage() {
+    return "Get ready for level 3!!!";
+  }
+
+
+  @Override
+  protected GameObject createSingleEnemy(String name, double x_enemy, double y_enemy,
+      double vx_enemy, double vy_enemy, ObjectController enemyController, double gameTime) {
+    logger.trace("creating enemy [" + name + "] with ZickZackController ");
+    ObjectController zzController = new ZickZackController(gameTime, 0.5);
+    GameObject go = new AnimatedGameobject(name, this, x_enemy, y_enemy, vx_enemy, vy_enemy,
+        ENEMYSCALE, this.enemyAnim, this.getGameTime(), "loop").addController(zzController)
+            .generateColliders();
+
+    return go.generateColliders();
+  }
+
+
+
+}
--- a/src/playground/Level4.java
+++ b/src/playground/Level4.java
@ -0,0 +1,63 @@
+package playground;
+
+import gameobjects.GameObject;
+import controller.LimitedTimeController;
+import gameobjects.TextObject;
+import java.awt.Color;
+import org.apache.logging.log4j.LogManager;
+import org.apache.logging.log4j.Logger;
+
+
+
+/**
+ * extends extends {@link SpaceInvadersLevel}
+ * <ul>
+ * <li>Hit aliens twice to kill them
+ * <li>they say AUA when not destroyed
+ * </ul>
+ */
+public class Level4 extends SpaceInvadersLevel {
+
+  /** constant defining the number of shots needed to destroy an enemy */
+  public static final int MAX_HITS = 2;
+
+  private static Logger logger = LogManager.getLogger(Level4.class);
+
+  @Override
+  protected String getStartupMessage() {
+    return "Jetzt gibts Saures!";
+  }
+
+  @Override
+  void actionIfEnemyIsHit(GameObject e, GameObject shot) {
+    double gameTime = this.getGameTime();
+
+    Object counterFlag = e.getOrCreateObjectFlag("counter", Integer.valueOf(1));
+
+    int counter = (Integer) counterFlag;
+
+    if (counter >= MAX_HITS) {
+      logger.trace("enemy was hit before for " + counter + " times, which is above "
+          + LevelHitTwice.MAX_HITS);
+      super.actionIfEnemyIsHit(e, shot);
+    } else {
+      logger.trace("enemy was hit before for "+counter+" times, which is below "+LevelHitTwice.MAX_HITS);
+      e.setObjectFlag("counter", Integer.valueOf(counter + 1));
+      // spawn a bonus points object
+      double vx = 2 * (Math.random() - 0.5) * SHARDSPEED + e.getVX();
+      double vy = 2 * (Math.random() - 0.5) * SHARDSPEED + e.getVY();
+      logger.trace("creating new TextObject bonus" + e.getId());
+      LimitedTimeController bonusTextController =
+          new LimitedTimeController(gameTime, SpaceInvadersLevel.EXPL_DURATION);
+      GameObject bonusText = new TextObject("bonus" + e.getId(), this, e.getX(), e.getY(), vx, vy,
+          "Aua", 20, Color.YELLOW).addController(bonusTextController);
+
+      this.addObject(bonusText);
+    }
+    deleteObject(shot.getId());
+
+  }
+
+
+
+}
--- a/src/playground/LevelBoss.java
+++ b/src/playground/LevelBoss.java
@ -0,0 +1,112 @@
+package playground;
+
+import java.awt.Color;
+import org.apache.logging.log4j.LogManager;
+import org.apache.logging.log4j.Logger;
+import controller.EgoController;
+import controller.FallingStarController;
+import controller.ObjectController;
+import gameobjects.AnimatedGameobject;
+import gameobjects.EgoObject;
+import gameobjects.FallingStar;
+import gameobjects.GameObject;
+import gameobjects.TextObject;
+
+/**
+ * Class that realizes all the game logic of a very simple game level. The level contains for now
+ * only two objects that are {@link GameObject} subclasses: {@link FallingStar} and
+ * {@link EgoObject}. Functions performed by this class are:
+ * <ul>
+ * <li>initially set up the level, spawn all object etc., in method {@link #prepareLevel}
+ * <li>React to keyboard commands in method {@link #processKeyEvents(java.util.Stack)}
+ * <li>define basic object movement rules for all objects in the level in the various
+ * ObjectController subclasses: {@link EgoController} and {@link FallingStarController}.
+ * </ul>
+ */
+public class LevelBoss extends SpaceInvadersLevel {
+
+  private static int MAX_SHOTS = 10;
+  private static Logger logger = LogManager.getLogger(LevelBoss.class);
+
+  @Override
+  void actionIfEnemyIsHit(GameObject e, GameObject shot) {
+
+    Object counterFlag = e.getOrCreateObjectFlag("counter", Integer.valueOf(1));
+
+    int counter = (Integer) counterFlag;
+
+    if (counter >= LevelBoss.MAX_SHOTS) {
+      logger.trace("enemy was hit before for " + counter + " times, which is equal or above "
+          + LevelHitTwice.MAX_HITS);
+      super.actionIfEnemyIsHit(e, shot);
+    } else {
+      logger.trace("enemy was hit before for " + counter + " times, which is below "
+          + LevelHitTwice.MAX_HITS);
+      e.setObjectFlag("counter", Integer.valueOf(counter + 1));
+    }
+    deleteObject(shot.getId());
+  }
+
+
+
+  @Override
+  double calcEnemyShotProb() {
+    return 1.5 * this.getTimestep();
+  }
+
+  @Override
+  protected double calcEnemySpeedX() {
+    return ENEMYSPEEDX * 2;
+  }
+
+  @Override
+  protected double calcEnemySpeedY() {
+    return ENEMYSPEEDY * 2;
+  }
+
+  @Override
+  protected int calcNrEnemies() {
+    return (int) 1;
+  }
+
+  @Override
+  protected GameObject createEnemyShotObject(GameObject parentObject, String name,
+      ObjectController limitedTimeController) {
+    GameObject ego = this.getObject("ego");
+
+    double deltax = parentObject.getX() - ego.getX();
+    double deltay = parentObject.getY() - ego.getY();
+
+    double norm = Math.sqrt(deltax * deltax + deltay * deltay);
+    deltax *= -ENEMYSHOTSPEED / norm;
+    deltay *= -ENEMYSHOTSPEED / norm;
+
+    logger.trace("Creating EnemyShot as TextObject [" + name + "] in direction " + deltax + "/"
+        + deltay + " towards ego");
+    GameObject to = new TextObject(name, this, parentObject.getX(), parentObject.getY(), deltax,
+        deltay, "*", 20, Color.GREEN).generateColliders().addController(limitedTimeController);
+    return to;
+
+  }
+
+
+  @Override
+  protected GameObject createSingleEnemy(String name, double x_enemy, double y_enemy,
+      double vx_enemy, double vy_enemy, ObjectController enemyController, double gameTime) {
+
+    GameObject go = new AnimatedGameobject(name, this, this.canvasX / 2, 10, vx_enemy, 50,
+        ENEMYSCALE * 3, this.enemyAnim, this.getGameTime(), "loop").generateColliders()
+            .addController(enemyController);
+
+    return go;
+  }
+
+
+  @Override
+  protected String getStartupMessage() {
+    return "BOSS LEVEL!";
+  }
+
+
+
+}
--- a/src/playground/LevelHitTwice.java
+++ b/src/playground/LevelHitTwice.java
@ -0,0 +1,65 @@
+package playground;
+
+import controller.FallingStarController;
+import gameobjects.EgoObject;
+import gameobjects.FallingStar;
+import gameobjects.GameObject;
+import gameobjects.RectObject;
+import java.awt.Color;
+import org.apache.logging.log4j.LogManager;
+import org.apache.logging.log4j.Logger;
+
+
+
+/**
+ * extends {@link SpaceInvadersLevel} with 10 enemies that need two shots each to be destroyed.
+ * 
+ */
+
+
+public class LevelHitTwice extends SpaceInvadersLevel {
+
+  /** constant defining the number of shots needed to destroy an enemy */
+  public static final int MAX_HITS = 2;
+  
+  private static Logger logger = LogManager.getLogger(LevelHitTwice.class);
+
+  /** constructor setting internal name to 'hitTwice' */
+  public LevelHitTwice() {
+    super();
+    this.level = "hitTwice";
+  }
+
+
+  @Override
+  protected String getStartupMessage() {
+    return "2 shots at alien required!!!";
+  }
+
+  @Override
+  protected int calcNrEnemies() {
+    return 10;
+  }
+
+
+
+  @Override
+  void actionIfEnemyIsHit(GameObject e, GameObject shot) {    
+    Object counterFlag = e.getOrCreateObjectFlag("counter", Integer.valueOf(1));
+
+    int counter = (Integer) counterFlag;
+
+    if (counter >= MAX_HITS) {
+      logger.trace("enemy was hit before for " + counter + " times, which is above "
+          + LevelHitTwice.MAX_HITS);
+      super.actionIfEnemyIsHit(e, shot);
+    } else {
+      logger.trace("enemy was hit before for "+counter+" times, which is below "+LevelHitTwice.MAX_HITS);
+      e.setObjectFlag("counter", Integer.valueOf(counter + 1));
+    }
+    deleteObject(shot.getId());
+  }
+
+
+
+}
--- a/src/playground/Music.java
+++ b/src/playground/Music.java
@ -0,0 +1,48 @@
+package playground;
+
+import java.io.File;
+import javax.sound.sampled.AudioInputStream;
+import javax.sound.sampled.AudioSystem;
+import javax.sound.sampled.Clip;
+import javax.sound.sampled.FloatControl;
+
+public class Music {
+  private static final float volume = 0.02f; // scale 0 silence, 1 no change, 2 double. (linear).
+
+  public static synchronized void music(File track) {
+
+    final File trackname = track;
+
+    new Thread(new Runnable() {
+
+      @Override
+      public void run() {
+        while (true) {
+
+          try {
+
+            Clip clip = AudioSystem.getClip();
+            AudioInputStream inputstream = AudioSystem.getAudioInputStream(trackname);
+            clip.open(inputstream);
+            FloatControl volumeControl =
+                (FloatControl) clip.getControl(FloatControl.Type.MASTER_GAIN);
+            if (volumeControl != null) {
+              volumeControl.setValue(20f * (float) Math.log10(volume));
+            }
+            clip.start();
+
+            Thread.sleep(clip.getMicrosecondLength() / 1);
+
+          } catch (Exception e) {
+            e.printStackTrace();
+          }
+
+        }
+
+      }
+
+    }).start();
+
+  }
+
+}
--- a/src/playground/Playground.java
+++ b/src/playground/Playground.java
@ -0,0 +1,374 @@
+package playground;
+
+import java.awt.Graphics2D;
+import java.util.HashMap;
+import java.util.LinkedList;
+import java.util.Map;
+import java.util.Stack;
+import java.awt.event.*;
+import gameobjects.GameObject;
+import org.apache.logging.log4j.Logger;
+import org.apache.logging.log4j.LogManager;
+
+/**
+ * Playground represents a level of the game, focusing on the game LOGIC, i.e., not so much on the
+ * graphical representation. In particular, an instance of Playground
+ * <ul>
+ * <li>manages the different moving or static objects in a level (e.g., collisions, adding objects,
+ * removing objects). This is mainly done by the methods {@link #addObject}, {@link #deleteObject}.
+ * <li>processes keyboard inputs provided by GameLoop in {@link #processKeyEvents(Stack)} and
+ * {@link #processMouseEvents(Stack)}
+ * <li>represents the state of a level represented by <b>flags</b>. Each flag has a name (a String)
+ * and an arbitrary value of any type. Methods: {@link #setLevelFlag(String, Object)},
+ * {@link #getLevelFlag(String)}. As an example, the current score is a flag usually named "points",
+ * with an Integer as a value. This value can be retrieved and manipulated using the above mentioned
+ * methods.
+ * </ul>
+ */
+public abstract class Playground {
+
+  public static final int FLAGS_GLOBAL = 1;
+  public static final int FLAGS_LEVEL = 2;
+  public static final int FLAGS_ALL = 3;
+  protected int canvasX = -1;
+  protected int canvasY = -1;
+
+  /** only one set of objects exists concurrently so this can be static */
+  protected static HashMap<String, GameObject> gameObjects = new HashMap<String, GameObject>();
+
+  /** only one set of objects exists concurrently so this can be static */
+  protected static HashMap<String, Object> flags = new HashMap<String, Object>();
+
+  protected String level = "";
+  protected double timeStep = 0;
+  protected double gameTime = 0;
+  LinkedList<GameObject> addables = new LinkedList<GameObject>();
+  LinkedList<String> removables = new LinkedList<String>();
+  // HashMap<Integer,Integer> keys ;
+  Stack<KeyEvent> keyEvents;
+  Stack<MouseEvent> mouseEvents;
+
+  protected boolean pausedFlag = false;
+
+  private static Logger logger = LogManager.getLogger(Playground.class);
+
+  public Playground() {
+    this.canvasX = -1;
+    this.canvasY = -1;
+  }
+
+  // here, the level communicates its size preference to the GameUI
+  // called automatically
+  public abstract int preferredSizeX();
+
+  public abstract int preferredSizeY();
+
+  /**
+   * Adds a graphics object to a level.
+   * 
+   * @param o GameObject The object to be added
+   */
+  public void addObject(GameObject o) {
+    // gameObjects.put(o.getId(), o);
+    addables.addLast(o);
+  }
+
+  /**
+   * Adds a graphics object to a level.
+   * 
+   * @param o GameObject The object to be added
+   */
+  public void addObjectNow(GameObject o) {
+    gameObjects.put(o.getId(), o);
+  }
+
+
+  /**
+   * Puts objects with a certain substring in their name into a LinkedLisrt and returns them.
+   * 
+   * @param substr The string that must be part of the object name if object is to be considered
+   *        found.
+   * @param filterInactive if set true only active objects are considered.
+   * @return a reference to a LinkedList filled with all objects that have <b>substr</b> in their
+   *         name
+   */
+  public LinkedList<GameObject> collectObjects(String substr, boolean filterInactive) {
+    LinkedList<GameObject> l = new LinkedList<GameObject>();
+    for (Map.Entry<String, GameObject> entry : Playground.gameObjects.entrySet()) { // Iterator
+                                                                                    // usage
+      GameObject obj = entry.getValue();
+      if (obj.getId().contains(substr)) {
+        if (filterInactive == true) {
+          if (obj.isActive()) {
+            l.add(obj);
+          }
+        } else {
+          l.add(obj);
+        }
+      }
+    }
+    return l;
+  };
+
+
+  /**
+   * Removes a graphics object from a level.
+   * 
+   * @param id String The unique identifier of the object
+   */
+  public void deleteObject(String id) {
+    // gameObjects.remove(id);
+    removables.addLast(id);
+  }
+
+  /**
+   * Removes a graphics object from a level immediately, CAUTION.
+   * 
+   * @param id String The unique identifier of the object
+   */
+  public void deleteObjectNow(String id) {
+    gameObjects.remove(id);
+  }
+
+
+  /**
+   * Retrieves a graphics object by name.
+   * 
+   * @param id String Unique id of the object
+   * @return reference to the requested game object, or null if not found
+   */
+  public GameObject getObject(String id) {
+    return gameObjects.get(id);
+  }
+
+  /**
+   * Sets a level-wide permanent flag.
+   * 
+   * @param flag String Q unique name in this level. If it exists value is overwritten.
+   * @param value Object Any Object can be the value of a flag!
+   */
+
+  public static void setGlobalFlag(String flag, Object value) {
+    flags.put("/global/" + flag, value);
+  }
+
+  public Object setLevelFlag(String flag, Object value) {
+    flags.put("/" + this.level + "/" + flag, value);
+    return value;
+  }
+
+  /**
+   * mode can be: FLAGS_ALL (all), FLAGS_GLOBAL(global), FLAGs_LEVEL(level)
+   * 
+   * @param mode can be only one of {@link #FLAGS_GLOBAL} {@link #FLAGS_ALL} or
+   *        {@link #FLAGS_LEVEL }
+   */
+  public void resetFlags(int mode) {
+    LinkedList<String> delKeys = new LinkedList<String>();
+    for (Map.Entry<String, Object> entry : Playground.flags.entrySet()) {
+      logger.trace(entry.getKey() + " IndexofGlobal = " + entry.getKey().indexOf("/global/"));
+      if ((mode == FLAGS_GLOBAL) && (entry.getKey().indexOf("/global/") != -1)) {
+        logger.debug("GLOBAL: scheduling for removal: " + entry.getKey());
+        delKeys.add(entry.getKey());
+      } else if ((mode == FLAGS_LEVEL) && (entry.getKey().indexOf("/global/") == -1)) {
+        logger.debug("LEVEL: scheduling for removal: " + entry.getKey());
+        delKeys.add(entry.getKey());
+      } else if (mode == FLAGS_ALL) {
+        logger.debug("ALL: scheduling for removal: " + entry.getKey());
+        delKeys.add(entry.getKey());
+      }
+    }
+
+    for (String str : delKeys) {
+      logger.trace("removing key " + str);
+      flags.remove(str);
+    }
+  }
+
+
+  /**
+   * Retrieves a level-wide flag by name.
+   * 
+   * @param flag String Unique flag id
+   * @return the value associated with <b>flag</b>, or <b>null</b> if the flag does not exist.
+   */
+  public static Object getGlobalFlag(String flag) {
+    return flags.get("/global/" + flag);
+  }
+
+  /** checks for existence and if not creates the new global flag with the given initial value. Returns the value.
+   *  afterwards it is guaranteed that no priorly existing value is overridden and that it definitely exists (created if not present before). 
+  * 
+   * @param flag  String name for the global flag  (created if not present)
+   * @param value Object value to be stored (used only if flag was not present)
+   * @return the current value of the flag (maybe the initial one in case flag was not there before)
+   */
+  public static Object getOrCreateGlobalFlag(String flag, Object value) {
+    Object tmp = getGlobalFlag(flag);
+    if (tmp == null) {
+      setGlobalFlag(flag, value);
+      return value;
+    } else {
+      return tmp;
+    }
+  }
+
+
+  public Object getLevelFlag(String flag) {
+    return flags.get("/" + this.level + "/" + flag);
+  }
+
+  public Object getOrCreateLevelFlag(String flag, Object createValue) {
+    Object tmp = getLevelFlag(flag);
+    if (tmp == null) {
+      return setLevelFlag(flag, createValue);
+    } else {
+      return tmp;
+    }
+  }
+
+
+  /**
+   * Reinitializes the level.
+   */
+  public void reset() {
+    gameObjects.clear();
+  }
+
+  public boolean isPaused() {
+    return this.pausedFlag;
+  }
+
+  public void setPaused(boolean p) {
+    this.pausedFlag = p;
+  }
+
+  public void togglePause() {
+    pausedFlag = !pausedFlag;
+
+  }
+
+
+  /**
+   * Method meant to be filled with own code, processes Keyboard inputs.
+   * 
+   * @param keyEvents all collected {@link KeyEvent}s collected since last game loop.
+   */
+
+  public void processKeyEvents(Stack<KeyEvent> keyEvents) {
+    this.keyEvents = keyEvents;
+    Playground.setGlobalFlag("inputs", keyEvents);
+  }
+
+
+  public void processMouseEvents(Stack<MouseEvent> mouseEvents) {
+    this.mouseEvents = mouseEvents;
+    Playground.setGlobalFlag("inputs", mouseEvents);
+  }
+
+
+  public Stack<KeyEvent> getKeyEvents() {
+    return this.keyEvents;
+  }
+
+  public Stack<MouseEvent> getMouseEvents() {
+    return this.mouseEvents;
+  }
+
+
+  /**
+   * Method meant to be filled with own code, handles the entore game logic (collision checks, timed
+   * events, ...).
+   * 
+   */
+  public abstract void applyGameLogic();
+
+  /**
+   * Sets up a single level. Prepares all objects etc.
+   * 
+   * @param level String a string identifying the level number etc
+   */
+  public abstract void prepareLevel(String level);
+
+  public abstract boolean gameOver();
+
+  public abstract boolean levelFinished();
+
+  public int getSizeX() {
+    return canvasX;
+  }
+
+  public int getSizeY() {
+    return canvasY;
+  }
+
+  /**
+   * Calls all object update methods in level. Internal, never call directly.
+   * 
+   */
+  public void updateObjects() {
+    for (GameObject gameObject : gameObjects.values()) { // Iterator usage
+      if (gameObject.isActive() == true) {
+        gameObject.updateObject();
+        logger.trace("updated object " + gameObject.scol);
+      }
+    }
+
+    for (GameObject o : addables) { // Iterator usage
+      addObjectNow(o);
+    }
+
+    for (String s : removables) { // Iterator usage
+      deleteObjectNow(s);
+    }
+    removables.clear();
+    addables.clear();
+  }
+
+  public void setTimestep(double s) {
+    timeStep = s;
+  }
+
+  public double getTimestep() {
+    return timeStep;
+  }
+
+  /** set the game time value (in seconds)
+   *
+   * @param s  seconds the game is running
+   */
+  public void setGameTime(double s) {
+    this.gameTime = s;
+  }
+
+  /** returns time in seconds since level start */
+  public double getGameTime() {
+    return this.gameTime;
+  }
+
+
+  /**
+   * To be redefined!! Draws mainly h level background and global information like points etc.
+   * 
+   * @param g2 Graphics2D abstract drawing object of java Swing, used to carry out all drawing
+   *        operations.
+   */
+  public abstract void redrawLevel(Graphics2D g2);
+
+  /**
+   * Internal, do not call directly.
+   * 
+   * @param g2 Graphics2D abstract drawing object of java Swing, used to carry out all drawing
+   *        operations.
+   */
+  public void redraw(Graphics2D g2) {
+    redrawLevel(g2);
+    for (GameObject gameObject : gameObjects.values()) {
+      if (gameObject.isActive()) {
+        gameObject.draw(g2);
+      }
+    }
+  }
+
+
+}
--- a/src/playground/SaveGame.java
+++ b/src/playground/SaveGame.java
@ -0,0 +1,62 @@
+package playground;
+
+import java.io.FileInputStream;
+import java.io.FileNotFoundException;
+import java.io.FileOutputStream;
+import java.io.IOException;
+import java.io.ObjectInputStream;
+import java.io.ObjectOutputStream;
+import java.util.ArrayList;
+import org.apache.logging.log4j.Logger;
+import org.apache.logging.log4j.LogManager;
+
+public class SaveGame {
+
+  private static String datnam = "aktuellerSpielzustand.ser";
+  private static Logger logger = LogManager.getLogger(SaveGame.class);
+
+
+  @SuppressWarnings("unchecked")
+  public static void save() {
+
+    // gameobjects.AnimatedGameobject
+    ArrayList<String> objArrList = null;
+    ObjectInputStream in = null;
+    try {
+      in = new ObjectInputStream(new FileInputStream(datnam));
+      objArrList = (ArrayList<String>) in.readObject();
+    } catch (FileNotFoundException ex) {
+      logger.warn("Savegame file not (yet) existing!");
+    } catch (Exception ex) {
+      logger.error(ex);
+    } finally {
+      try {
+        if (in != null)
+          in.close();
+      } catch (IOException e) {
+      }
+    }
+    if (objArrList == null)
+      objArrList = new ArrayList<String>();
+
+    objArrList.add(new String("ArrayListgroesse: " + objArrList.size()));
+    logger.debug(objArrList);
+
+    ObjectOutputStream aus = null;
+    try {
+      aus = new ObjectOutputStream(new FileOutputStream(datnam));
+      aus.writeObject(objArrList);
+    } catch (IOException ex) {
+      logger.error(ex);
+    } finally {
+      try {
+        if (aus != null) {
+          aus.flush();
+          aus.close();
+        }
+      } catch (IOException e) {
+      }
+    }
+  }
+
+}
--- a/src/playground/SpaceInvadersLevel.java
+++ b/src/playground/SpaceInvadersLevel.java
@ -0,0 +1,678 @@
+package playground;
+
+// import utilities.* ;
+import java.awt.Color;
+import java.awt.Font;
+import java.awt.Graphics2D;
+import java.awt.Polygon;
+import java.awt.RenderingHints;
+import java.awt.font.TextAttribute;
+import java.awt.image.BufferedImage;
+import java.io.*;
+import java.text.AttributedString;
+import java.util.LinkedList;
+import controller.EnemyController;
+import controller.FallingStarController;
+import controller.LimitedTimeController;
+import controller.ObjectController;
+import controller.EgoController;
+import controller.CollisionAwareEgoController;
+import gameobjects.AnimatedGameobject;
+import gameobjects.FallingStar;
+import gameobjects.GameObject;
+import gameobjects.EgoObject;
+import gameobjects.TextObject;
+import org.apache.logging.log4j.Logger;
+import org.apache.logging.log4j.LogManager;
+
+/**
+ * Class that realizes all the game logic of a very simple game level. The level contains for now
+ * only two objects that are {@link GameObject} subclasses: {@link FallingStar} and
+ * {@link EgoObject}. Functions performed by this class are:
+ * <ul>
+ * <li>initially set up the level, spawn all object etc., in method {@link #prepareLevel}
+ * <li>React to game events in {@link #actionIfEgoCollidesWithCollect(GameObject, GameObject)} ,
+ * {@link #actionIfEgoCollidesWithEnemy(GameObject, GameObject)}, etc.
+ * <li>define basic object movement rules for all objects in the level in the various
+ * ObjectController subclasses: {@link EgoController} and {@link FallingStarController}.
+ * </ul>
+ */
+public class SpaceInvadersLevel extends Playground {
+
+  public static final double SHOTSPEED = 175;
+  public static final double EGOSPEED = 220;
+  protected static final int LEVEL2STARS = 80;
+  protected static final double BONUS_DURATION = 1.;
+  protected static final double ENEMYSPEEDX = 60;
+  protected static final double ENEMYSPEEDY = 40;
+  protected static final double ENEMYSCALE = 1.0;
+  protected static final double ENEMYSHOTSPEED = 75;
+  protected static final int NRSHARDS = 50;
+  protected static final double EXPL_DURATION = 1.;
+  protected static final int NR_ENEMIES = 30;
+  protected static final int NR_COLLECT = 5;
+  protected static final Color EXPL_COLOR = Color.RED;
+  protected static final double SHARDSPEED = 200;
+  protected static final double STARSPEED = 100;
+  protected static final double STARTTEXTSPEED = 75;
+  protected static final double STARTPERIOD = 5.;
+  protected static final double DYING_INTERVAL = 2.0;
+  protected static final int CANVASX = 700;
+  protected static final int CANVASY = 700;
+  protected static final double EGORAD = 15;
+  protected static final double LEVEL_INIT_TIME = 1.0;
+
+  protected int nextShot = 0;
+
+  protected boolean lost = false;
+  protected boolean doneLevel = false;
+  protected double starttime = 0;
+  protected File smash = null;
+  protected File laser = null;
+
+  protected BufferedImage[] alienImage = null;
+  protected double[] alienshowTime = null;
+
+  protected BufferedImage[] heartImage = null;
+  protected double[] heartshowTime = null;
+
+  protected Animation enemyAnim = null;
+  protected Animation heartAnim = null;
+
+  private static Logger logger = LogManager.getLogger(SpaceInvadersLevel.class);
+
+  public SpaceInvadersLevel() {
+    super();
+    this.canvasX = this.preferredSizeX();
+    this.canvasY = this.preferredSizeY();
+  }
+
+
+  /**
+   * initially sets up the level. Not called by user interaction, but called every time a layer is
+   * restarted from scratch. So make sure that this is possible. Here, resources are loaded only
+   * once even if method is called several times.
+   * 
+   * @param id String identifies level.
+   */
+  @Override
+  public void prepareLevel(String id) {
+    logger.info("PREPARE");
+    reset();
+    this.doneLevel = false;
+    this.lost = false;
+    resetFlags(FLAGS_LEVEL);
+
+    // set up flags that some objects rely on
+    setLevelFlag("delete", new LinkedList<String>());
+    setLevelFlag("replace", new LinkedList<String>());
+    getOrCreateGlobalFlag("points", Integer.valueOf(0));
+    setLevelFlag("enemyShotCounter", Integer.valueOf(0));
+    setLevelFlag("gameStatus", "start");
+    setLevelFlag("detailedStatus", "std");
+    getOrCreateGlobalFlag("egoLives", Integer.valueOf(5));
+    setLevelFlag("dying", Double.valueOf(-1));
+
+    // start time measure
+    this.starttime = this.getGameTime();
+
+    // music load
+    if (this.smash == null) {
+      this.smash = new File("./audio/smash.wav");
+    }
+    if (this.laser == null) {
+      this.laser = new File("./audio/laser.wav");
+    }
+
+    // ----- Alien
+    if (this.enemyAnim == null) {
+      String dateiName = "./video/sweetAlien.txt";
+      this.enemyAnim = new Animation(dateiName);
+    }
+
+    // -----Heart
+    if (this.heartAnim == null) {
+      String heartName = "./video/heart.txt";
+      this.heartAnim = new Animation(heartName);
+    }
+
+    // load highscore and update
+    HighscoreManager dh = new HighscoreManager();
+    int alltimeHighscore = dh.readHSFromFile();
+    setGlobalFlag("highscore", alltimeHighscore);
+    logger.info("HIGHSCORE" + alltimeHighscore);
+  }
+
+
+  /**
+   * (re)draws the level but NOT the objects, they draw themselves. Called by the main game loop.
+   * This method mainly draws the background and the scoreboard.
+   * 
+   * @param g2 Graphics2D object that can, and should be, draw on.
+   */
+  @Override
+  public void redrawLevel(Graphics2D g2) {
+    // Set anti-alias!
+    g2.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_OFF);
+    // Set anti-alias for text
+    g2.setRenderingHint(RenderingHints.KEY_TEXT_ANTIALIASING,
+        RenderingHints.VALUE_TEXT_ANTIALIAS_OFF);
+
+    // fill background with black
+    int[] x = {0, canvasX, canvasX, 0};
+    int[] y = {0, 0, canvasY, canvasY};
+    Polygon bg = new Polygon(x, y, 4);
+    g2.setColor(Color.BLACK);
+    g2.fill(bg);
+
+    // draw score in upper left part of playground
+    Integer pts = (Integer) getGlobalFlag("points");
+    Font drawFont = new Font("SansSerif", Font.PLAIN, 20);
+    AttributedString as = new AttributedString("Points: " + pts);
+    as.addAttribute(TextAttribute.FONT, drawFont);
+    as.addAttribute(TextAttribute.FOREGROUND, Color.yellow);
+    g2.drawString(as.getIterator(), 10, 20);
+
+    // draw lives counter in upper left part of playground
+    Integer lives = (Integer) getGlobalFlag("egoLives");
+    Font drawFont2 = new Font("SansSerif", Font.PLAIN, 20);
+    AttributedString as2 = new AttributedString("Lives: " + lives);
+    as2.addAttribute(TextAttribute.FONT, drawFont2);
+    as2.addAttribute(TextAttribute.FOREGROUND, Color.yellow);
+    g2.drawString(as2.getIterator(), canvasX - 100, 20);
+
+    // draw highscore in left part of playground under score
+    Integer highscore = (Integer) getGlobalFlag("highscore");
+    Font drawFont3 = new Font("SansSerif", Font.PLAIN, 20);
+    AttributedString as3 = new AttributedString("Highscore: " + highscore);
+    as3.addAttribute(TextAttribute.FONT, drawFont3);
+    as3.addAttribute(TextAttribute.FOREGROUND, Color.yellow);
+    g2.drawString(as3.getIterator(), 10, 40);
+
+    if (isPaused()) {
+      Font drawFont4 = new Font("SansSerif", Font.PLAIN, 50);
+      AttributedString as4 = new AttributedString("Das Spiel wurde pausiert.");
+      as4.addAttribute(TextAttribute.FONT, drawFont4);
+      as4.addAttribute(TextAttribute.FOREGROUND, Color.red);
+      g2.drawString(as4.getIterator(), 30, 400);
+    }
+
+  }
+
+
+  /**
+   * applies the logic of the level: For now, this is just about deleting shots that are leaving the
+   * screen and calling methods 'actionIf..' in case objects collide.
+   *
+   */
+  @Override
+  public void applyGameLogic() {
+    double gameTime = this.getGameTime();
+    String gameStatus = (String) getLevelFlag("gameStatus");
+    String subStatus = (String) getLevelFlag("detailedStatus");
+
+    if (gameStatus.equals("start") == true) {
+      setupInitialState();
+
+    } else if (gameStatus.equals("starting") == true) {
+
+      if ((gameTime - starttime) > LEVEL_INIT_TIME) {
+        setLevelFlag("gameStatus", "init");
+      }
+
+    } else if (gameStatus.equals("init") == true) {
+
+      this.createEnemies();
+      this.createCollectables();
+
+      setLevelFlag("gameStatus", "playing");
+
+    } else if (gameStatus.equals("playing") == true) {
+      GameObject s = this.getObject("ego");
+
+      if (subStatus.equals("std")) {
+
+        // check for collisions of enemy and shots, reuse shots list from before..
+        LinkedList<GameObject> enemies = collectObjects("enemy", false);
+
+        // check whether all enemies have been destroyed or escaped
+        if (enemies.size() == 0) {
+          HighscoreManager hsm = new HighscoreManager();
+          HighscoreManager.writeHSToFile((Integer) Playground.getGlobalFlag("points"),
+              (Integer) Playground.getGlobalFlag("highscore"));
+          this.doneLevel = true;
+          logger.info("no enemies left, level done.");
+        }
+
+        // loop over enemies to check for collisions or suchlike ...
+        LinkedList<GameObject> shots = collectObjects("simpleShot", true);
+        for (GameObject e : enemies) {
+          // if ego collides with enemy..
+          if (s.collisionDetection(e)) {
+            actionIfEgoCollidesWithEnemy(e, s);
+          }
+
+          // if shot collides with enemy
+          for (GameObject shot : shots) {
+            if (e.collisionDetection(shot)) {
+              actionIfEnemyIsHit(e, shot);
+            }
+          }
+        }
+
+        // collecting hearts
+        LinkedList<GameObject> collects = collectObjects("collect", false);
+        for (GameObject c : collects) {
+          if (s.collisionDetection(c)) {
+            actionIfEgoCollidesWithCollect(c, s);
+          }
+        }
+
+        // loop over enemies and, with a certain probability, launch an enemy shot for each one
+        for (GameObject e : enemies) {
+          createEnemyShot(e);
+        }
+
+        // check for collisions between ego object and enemy shots
+        LinkedList<GameObject> eshots = collectObjects("enmyShot", true);
+        for (GameObject eshot : eshots) {
+
+          if (s.collisionDetection(eshot)) {
+            logger.trace("COLLISION" + eshot.scol.get(0) + "/" + s.scol.get(0));
+            actionIfEgoObjectIsHit(eshot, s);
+          }
+        }
+      } // if substatus..
+      else if (subStatus.equals("dying")) {
+        Double t0 = (Double) getLevelFlag("t0");
+        if (gameTime - t0 > DYING_INTERVAL) {
+          LinkedList<GameObject> enemies = collectObjects("enemy", false);
+          setLevelFlag("detailedStatus", "std");
+          s.setActive(true);
+
+          for (GameObject e : enemies) {
+            logger.trace("activating" + e.getId());
+            e.setActive(true);
+          }
+        }
+      }
+
+    } // if (gameStatus == "playing")
+
+
+  }
+
+
+  public boolean gameOver() {
+    return lost;
+  }
+
+
+  public boolean levelFinished() {
+    return doneLevel;
+  }
+
+
+  /**
+   * calculates and returns the preferred size of the level (in pixel) for X-direction
+   */
+  public int preferredSizeX() {
+    return CANVASX;
+  }
+
+  /**
+   * calculates and returns the preferred size of the level (in pixel) for Y-direction
+   */
+  public int preferredSizeY() {
+    return CANVASY;
+  }
+
+
+  /** Adds ego object and stars and displays startup message. Is called from applyGameLogic */
+  protected void setupInitialState() {
+    double gameTime = this.getGameTime();
+    setLevelFlag("gameStatus", "starting");
+
+    this.createStars();
+
+    // set up ego object
+    this.createEgoObject();
+
+    // add text object to playground
+    ObjectController ctrl = new LimitedTimeController(gameTime, 3.);
+    GameObject readyText = new TextObject("ready?", this, getSizeX() / 2, 0, 0, 100,
+        this.getStartupMessage(), 50, Color.RED).addController(ctrl);
+    addObject(readyText);
+
+  }
+
+
+  /**
+   * simply returns the text that should be displayed at level start
+   * 
+   * @return a string that is displayed at start. Should be not longer than 30 characters.
+   */
+  protected String getStartupMessage() {
+    return "Get ready for level X!";
+  }
+
+
+  /**
+   * returns a number representing the speed of an enemy object in X direction (pixels/second)
+   * 
+   * @return a positive value
+   */
+  protected double calcEnemySpeedX() {
+    return SpaceInvadersLevel.ENEMYSPEEDX;
+  }
+
+
+  /**
+   * returns a number representing the speed of an enemy object in Y direction (pixels/second)
+   * 
+   * @return a positive value
+   */
+  protected double calcEnemySpeedY() {
+    return SpaceInvadersLevel.ENEMYSPEEDY;
+  }
+
+  /**
+   * returns the maximum number of enemy instances (which are created at level start)
+   * 
+   * @return a positive value
+   */
+  protected int calcNrEnemies() {
+    return SpaceInvadersLevel.NR_ENEMIES;
+  }
+
+  /**
+   * returns the maximum number of collectables' instances (which are created at level start)
+   * 
+   * @return a positive value
+   */
+  protected int calcNrCollect() {
+    return SpaceInvadersLevel.NR_COLLECT;
+  }
+
+
+  protected GameObject createEnemyShotObject(GameObject parentObject, String name,
+      ObjectController limitedTimeController) {
+    GameObject to =
+        new TextObject(name, this, parentObject.getX(), parentObject.getY(), 0, ENEMYSHOTSPEED, "I",
+            20, Color.YELLOW).generateColliders().addController(limitedTimeController);
+    /*
+     * // also possible: GameObject to = new RectObject(name, this, parentObject.getX(),
+     * parentObject.getY(), 0, ENEMYSHOTSPEED, 4, 20,
+     * Color.YELLOW).addController(limitedTimeController) ; to.generateColliders();
+     */
+    return to;
+  }
+
+
+  protected void createEnemyShot(GameObject e) {
+    double gameTime = this.getGameTime();
+
+    double PROB = calcEnemyShotProb();
+    double diceThrow = Math.random();
+    Integer nrEnemyShots = (Integer) (getLevelFlag("enemyShotCounter"));
+    if (diceThrow < PROB) {
+      setLevelFlag("enemyShotCounter", Integer.valueOf(++nrEnemyShots));
+
+      LimitedTimeController limitedTimeController = new LimitedTimeController(gameTime, 10.);
+
+      GameObject textObject =
+          createEnemyShotObject(e, "enmyShot" + nrEnemyShots, limitedTimeController);
+
+      addObject(textObject);
+    }
+  }
+
+
+  /**
+   * calculates and returns the probability that an enemy shots. Used by
+   * {@link SpaceInvadersLevel#createEnemyShot(GameObject)}.
+   * 
+   * @return a positive value between 0 (no chance) to 1 (for sure).
+   */
+  double calcEnemyShotProb() {
+    return 0.1 * this.getTimestep();
+  }
+
+
+  ObjectController createEnemyController() {
+    return new EnemyController();
+  }
+
+
+  GameObject createSingleEnemy(String name, double x_enemy, double y_enemy, double vx_enemy,
+      double vy_enemy, ObjectController enemyController, double gameTime) {
+
+    GameObject tmp =
+        new AnimatedGameobject(name, this, x_enemy, y_enemy, vx_enemy, vy_enemy, ENEMYSCALE,
+            this.enemyAnim, gameTime, "loop").addController(enemyController).generateColliders();
+    return tmp;
+  }
+
+  GameObject createSingleCollect(String name) {
+    double gameTime = this.getGameTime();
+    double cspeedy = 20.;
+    double x_collect = Math.random() * this.canvasX;
+    double y_collect = Math.random() * this.canvasY / 3;
+    double vx_collect = 2 * (Math.random() - 0.5) * 0;
+    double vy_collect = Math.random() * cspeedy;
+
+    GameObject tmp = new AnimatedGameobject(name, this, x_collect, y_collect, vx_collect,
+        vy_collect, 0.3, this.heartAnim, gameTime, "loop").generateColliders()
+            .addController(new EnemyController());
+    return tmp;
+  }
+
+
+  void createEnemies() {
+    // create enemies
+    double gameTime = this.getGameTime();
+    double speedx = this.calcEnemySpeedX();
+    double speedy = this.calcEnemySpeedY();
+    for (int i = 0; i < this.calcNrEnemies(); i++) {
+      double x_enemy = Math.random() * this.canvasX;
+      double y_enemy = Math.random() * this.canvasY / 3;
+      double vx_enemy = 2 * (Math.random() - 0.5) * speedx;
+      double vy_enemy = Math.random() * speedy;
+
+      ObjectController enemyController = createEnemyController();
+      GameObject enemy = createSingleEnemy("enemy" + i, x_enemy, y_enemy, vx_enemy, vy_enemy,
+          enemyController, gameTime);
+      addObject(enemy);
+    }
+  }
+
+  void createCollectables() {
+    double gameTime = this.getGameTime();
+    // create collectables
+    for (int i = 0; i < this.calcNrCollect(); i++) {
+
+
+      GameObject collect = createSingleCollect("collect" + i);
+
+      addObject(collect);
+    }
+  }
+
+
+  void createEgoObject() {
+    // add ego to playground at lower bottom
+    EgoController egoController =
+        new CollisionAwareEgoController(SpaceInvadersLevel.EGORAD, this.laser);
+
+    GameObject ego = new EgoObject("ego", this, canvasX / 2, canvasY - (EGORAD * 2), 0, 0, EGORAD)
+        .addController(egoController).generateColliders();
+
+    addObject(ego);
+  }
+
+
+  void createStars() {
+    // add stars to playground
+    for (int i = 1; i <= LEVEL2STARS; i++) {
+      FallingStarController fsc = new FallingStarController();
+
+      GameObject star = new FallingStar("star" + i, this, Math.random() * canvasX,
+          Math.random() * 15, 0.0, Math.random() * STARSPEED, Color.WHITE, 1.).addController(fsc);
+
+      addObject(star);
+    }
+  }
+
+
+  void createExplosion(double gameTime, GameObject e, String basename, double interval,
+      Color color) {
+    // spawn a cloud of exploded shards
+    for (int i = 0; i < NRSHARDS; i++) {
+      double vx = 2 * (Math.random() - 0.5) * SHARDSPEED + e.getVX();
+      double vy = 2 * (Math.random() - 0.5) * SHARDSPEED + e.getVY();
+      addObject(
+          new FallingStar("shard" + gameTime + "/" + i, this, e.getX(), e.getY(), vx, vy, color, 2)
+              .addController(new LimitedTimeController(gameTime, interval)));
+    }
+  }
+
+
+  /**
+   * implements game behavior if an enemy object is hit by a players' shot. It creates an explosion
+   * effect, plays a sound and adds 200 points to the current score (and it removes the enemy object
+   * and the shot object).
+   * 
+   * @param e enemy which was hit
+   * @param shot the shot object that hit the enemy
+   */
+  void actionIfEnemyIsHit(GameObject e, GameObject shot) {
+
+    double gameTime = this.getGameTime();
+    createExplosion(gameTime, e, "shard", DYING_INTERVAL, Color.RED);
+
+    Music.music(smash);
+
+    // delete enemy
+    deleteObject(e.getId());
+
+    // delete shot
+    deleteObject(shot.getId());
+
+    // add to points counter
+    Integer pts = (Integer) getGlobalFlag("points");
+    setGlobalFlag("points", pts + 200);
+
+  }
+
+  /**
+   * implements game behavior if ego object of player touches a collectable
+   * {@link gameobjects.GameObject }. Here it adds one extra life and displays a text for a limited
+   * time on screen "Extra life!!". The duration is set in constant
+   * {@link SpaceInvadersLevel#EXPL_DURATION}.
+   * 
+   * 
+   * @param collect item touched by ego
+   * @param ego the players ego object
+   */
+  void actionIfEgoCollidesWithCollect(GameObject collect, GameObject ego) {
+    double gameTime = this.getGameTime();
+
+    if (this.getObject("bonustext") == null) {
+
+      // spawn a bonus points object
+      double vx = 2 * (Math.random() - 0.5) * SHARDSPEED + collect.getVX();
+      double vy = 2 * (Math.random() - 0.5) * SHARDSPEED + collect.getVY();
+
+
+      LimitedTimeController bonusTextController =
+          new LimitedTimeController(gameTime, SpaceInvadersLevel.EXPL_DURATION);
+      GameObject bonusText = new TextObject("bonustext", this, collect.getX(), collect.getY(), vx,
+          vy, "Extra life!!", 20, Color.YELLOW).addController(bonusTextController);
+
+      addObject(bonusText);
+
+      // delete collect
+      deleteObject(collect.getId());
+
+      // add to points counter
+      Integer lives = (Integer) getGlobalFlag("egoLives");
+      lives++;
+      setGlobalFlag("egoLives", lives);
+    }
+
+  }
+
+  /**
+   * implements behaviour of game when ego object is touching an enemy. It displays a text "AUAA!!"
+   * for a certain time on the game screen. Time span is defined as constant in
+   * {@link SpaceInvadersLevel#BONUS_DURATION } .
+   * 
+   * @param enemy the enemy that was hit
+   * @param ego the ego object of the player
+   */
+  void actionIfEgoCollidesWithEnemy(GameObject enemy, GameObject ego) {
+
+    /**
+     * set temporary text over ego. This object lives only for a short time. While it lives, further
+     * collisions are ignored. Otherwise a single collision would result in a lot of deducted
+     * points...
+     */
+
+    double gameTime = this.getGameTime();
+    GameObject auaObj = this.getObject("AUA-EGO");
+
+    if (auaObj == null) {
+      addObject(new TextObject("AUA-EGO", this, ego.getX(), ego.getY() - 20, ego.getVX(),
+          ego.getVY(), "AUAA!!", 10, Color.RED)
+              .addController(new LimitedTimeController(gameTime, BONUS_DURATION)));
+      // deduct points
+      Integer pts = (Integer) getGlobalFlag("points");
+      setGlobalFlag("points", pts - 500);
+    }
+
+  }
+
+  /**
+   * implements what happens if the eog object of player is hit by a shot. It removes the shot from
+   * screen, reduces lives by 1, removes the ego and end current playing.
+   * 
+   * @param eshot the shot object that hits the ego
+   * @param ego the ego object of the player
+   */
+  void actionIfEgoObjectIsHit(GameObject eshot, GameObject ego) {
+    logger.debug("collision of " + eshot.getId() + " and " + ego.getId());
+
+    double gameTime = this.getGameTime();
+    this.deleteObject(eshot.getId());
+
+    Integer oldLives = (Integer) getGlobalFlag("egoLives");
+    int newLives = oldLives - 1; 
+    setGlobalFlag("egoLives", newLives);
+    logger.debug("set egoLives to " + newLives + " (was " + oldLives + ")");
+
+    if (newLives <= 0) {
+      lost = true;
+      HighscoreManager.writeHSToFile((Integer) Playground.getGlobalFlag("points"),
+          (Integer) Playground.getGlobalFlag("highscore"));
+
+    }
+
+    LinkedList<GameObject> eshots = collectObjects("enmyShot", true);
+    for (GameObject _eshot : eshots) {
+      deleteObject(_eshot.getId());
+    }
+    setLevelFlag("detailedStatus", "dying");
+    setLevelFlag("t0", gameTime);
+    ego.setActive(false);
+    createExplosion(gameTime, ego, "egoexp", DYING_INTERVAL, Color.WHITE);
+    LinkedList<GameObject> enemies = collectObjects("enemy", false);
+    for (GameObject enemy : enemies) {
+      enemy.setY(0);
+      enemy.setActive(false);
+    }
+
+  }
+
+
+
+}
--- a/src/playground/SpaceInvadersLevelTest.java
+++ b/src/playground/SpaceInvadersLevelTest.java
@ -0,0 +1,81 @@
+package playground;
+
+import static org.junit.Assert.assertTrue;
+import java.awt.Color;
+import org.junit.jupiter.api.AfterAll;
+import org.junit.jupiter.api.BeforeAll;
+import org.junit.jupiter.api.Test;
+import gameobjects.EgoObject;
+import gameobjects.GameObject;
+import gameobjects.RectObject;
+
+/**
+ * Tests {@link SpaceInvadersLevel} for
+ * <ol>
+ * <li>calcEnemySpeedX() returns the same value as constant SpaceInvadersLevel.ENEMYSPEEDX
+ * <li>calcEnemySpeedY() returns the same value as constant SpaceInvadersLevel.ENEMYSPEEDY
+ * <li>calcNrEnemies() returns the same value as constant SpaceInvadersLevel.NR_ENEMIES
+ * <li>actionIfEnemyIsHit() adds 200 points to score
+ * <li>actionIfEgoObjectIsHit() reduces number of lives (egoLives)
+ * </ol>
+ * @author jkonert
+ *
+ */
+class SpaceInvadersLevelTest {
+
+  private static SpaceInvadersLevel myLevel;
+
+  @BeforeAll
+  static void setUpBeforeClass() throws Exception {
+    myLevel = new SpaceInvadersLevel();
+    SpaceInvadersLevel.setGlobalFlag("egoLives",  5);
+    SpaceInvadersLevel.setGlobalFlag("points",  500);
+    SpaceInvadersLevel.setGlobalFlag("highscore", 5000);
+  }
+
+  @AfterAll
+  static void tearDownAfterClass() throws Exception {
+    // nothing 
+  }
+
+  @Test
+  void testCalcEnemySpeedX() {
+    assertTrue("EnemySpeedX is as in SpaceInvadersLevel defined", myLevel.calcEnemySpeedX() == SpaceInvadersLevel.ENEMYSPEEDX);
+  }
+
+  @Test
+  void testCalcEnemySpeedY() {
+    assertTrue("EnemySpeedY is as in SpaceInvadersLevel defined", myLevel.calcEnemySpeedY() == SpaceInvadersLevel.ENEMYSPEEDY);
+  }
+
+  @Test
+  void testCalcNrEnemies() {
+    assertTrue("NrOfEnemies is as in SpaceInvadersLevel defined", myLevel.calcNrEnemies() == SpaceInvadersLevel.NR_ENEMIES);
+  }
+
+  
+  @Test
+  void testActionIfEnemyIsHitPointsUp() {
+    Integer numPointsBefore = (Integer)myLevel.getGlobalFlag("points");
+    GameObject dummyShot = new RectObject("shot1", myLevel, 0,0,0,0, 12, 12, Color.WHITE);
+    GameObject dummyEnemy = new RectObject("ego1", myLevel, 0,0,0,0, 12, 12, Color.BLACK);
+    myLevel.addObject(dummyShot);
+    myLevel.addObject(dummyEnemy);
+    myLevel.actionIfEnemyIsHit(dummyEnemy, dummyShot);;  // this is the call under test
+    Integer numPointsAfter = (Integer)myLevel.getGlobalFlag("points");  // changed?
+    assertTrue("numPoints is up +200 after EnemyIsHit", numPointsAfter == numPointsBefore + 200); // points are set +200 , check.
+  }
+
+  @Test
+  void testActionIfEgoObjectIsHitLivesDown() {
+    Integer numLivesBefore = (Integer)myLevel.getGlobalFlag("egoLives");
+    GameObject dummyShot = new RectObject("shot1", myLevel, 0,0,0,0, 12, 12, Color.RED);
+    GameObject dummyEgo = new EgoObject("ego1", myLevel, 0,0,0,0, 5);
+    myLevel.addObject(dummyShot);
+    myLevel.actionIfEgoObjectIsHit(dummyShot, dummyEgo);  // this is the call under test
+    Integer numLivesAfter = (Integer)myLevel.getGlobalFlag("egoLives");  // changed?
+    assertTrue("numLives is reduced by one ifEgoIsHit", numLivesAfter == numLivesBefore - 1); // lives is reduced by one
+    
+  }
+
+}
--- a/src/rendering/AnimationArtist.java
+++ b/src/rendering/AnimationArtist.java
@ -0,0 +1,93 @@
+package rendering;
+
+import gameobjects.GameObject;
+import playground.Animation;
+import java.awt.Graphics2D;
+import java.awt.image.BufferedImage;
+import java.util.LinkedList;
+import org.apache.logging.log4j.Logger;
+import org.apache.logging.log4j.LogManager;
+
+public class AnimationArtist extends Artist {
+
+  protected LinkedList<BufferedImage> imageArray;
+  protected LinkedList<Double> showtime;
+  protected double t0;
+
+  protected int loopFrame = 0;
+
+  protected double w = 0, h = 0, scale = 0;
+  protected String playmode = ""; // can be loop, forward, backward
+  private static Logger logger = LogManager.getLogger(AnimationArtist.class);
+
+
+  public AnimationArtist(GameObject go, Animation anim, double t0, String playmode, double scale) {
+    super(go);
+
+    this.imageArray = anim.getImageList();
+    this.showtime = anim.getShowtimeList();
+    this.t0 = t0;
+    logger.debug("AnimationArtist start = ") ;
+    this.loopFrame = 0;
+
+    for (int i = 0; i < imageArray.size(); i++) {
+      logger.trace("ANIMRAWWH="+imageArray.get(i).getWidth()) ;
+      this.w = Math.max(this.w, imageArray.get(i).getWidth());
+      this.h = Math.max(imageArray.get(i).getHeight(), this.h);
+    }
+    
+    logger.debug("AnimationArtist RAW WH = "+this.w+"/"+this.h) ;
+    
+    this.playmode = playmode;
+    this.w *= scale;
+    this.h *= scale;
+  }
+
+  public double getW() {
+    return w;
+  }
+
+  public double getH() {
+    return h;
+  }
+
+
+  @Override
+  public void draw(Graphics2D g) {
+    double i2 = this.getGameTime();
+
+    double elapsedTime = i2 - t0;
+
+    // Diff chance from sec to millis
+    double mseconds = (double) elapsedTime;
+     logger.debug("showtime= "+showtime.get(loopFrame)+" elapsed= "+elapsedTime+" i2= "+i2);
+
+    if (playmode.equals("loop")) {
+      if (mseconds >= showtime.get(loopFrame)) {
+        loopFrame++;
+        if (loopFrame >= imageArray.size())
+          loopFrame = 0;
+        t0 = i2;
+      }
+    }
+
+    if (playmode.equals("forward")) {
+      if (mseconds >= showtime.get(loopFrame) && loopFrame < imageArray.size() - 1) {
+        loopFrame++;
+        t0 = i2;
+      }
+    }
+
+    if (playmode.equals("backward")) {
+      if (mseconds >= showtime.get(loopFrame) && loopFrame > 1) {
+        loopFrame--;
+        t0 = i2;
+      }
+    }
+
+    g.drawImage(imageArray.get(loopFrame), (int) Math.round(this.getX() - w / 2.),
+        (int) Math.round(this.getY() - h / 2.), (int) w, (int) h, null);
+
+  }
+
+}
--- a/src/rendering/Artist.java
+++ b/src/rendering/Artist.java
@ -0,0 +1,40 @@
+package rendering;
+
+import gameobjects.GameObject;
+import java.awt.Graphics2D;
+
+public abstract class Artist {
+  protected GameObject gameObject;
+
+  Artist(GameObject go) {
+    this.gameObject = go;
+  }
+
+  public double getX() {
+    return this.gameObject.getX();
+  }
+
+
+  public double getY() {
+    return this.gameObject.getY();
+  }
+
+
+  public double getVX() {
+    return this.gameObject.getX();
+  }
+
+  public double getVY() {
+    return this.gameObject.getX();
+  }
+
+
+  public double getGameTime() {
+    return this.gameObject.getGameTime();
+  }
+
+
+
+  public abstract void draw(Graphics2D g);
+
+}
--- a/src/rendering/CircleArtist.java
+++ b/src/rendering/CircleArtist.java
@ -0,0 +1,34 @@
+package rendering;
+
+import gameobjects.GameObject;
+import java.awt.Color;
+import java.awt.Graphics2D;
+
+public class CircleArtist extends Artist {
+
+  protected double egoRad;
+  protected Color color;
+
+  public CircleArtist(GameObject go) {
+    super(go);
+    this.egoRad = 15.0;
+  }
+
+  public CircleArtist(GameObject go, double egoRad, Color color) {
+    super(go);
+    this.egoRad = egoRad;
+    this.color = color;
+  }
+
+  @Override
+  public void draw(Graphics2D g) {
+    g.setColor(this.color);
+    double x = this.getX();
+    double y = this.getY();
+    int posX = (int) (x - egoRad);
+    int posY = (int) (y - egoRad);
+    int rad = (int) (2 * egoRad);
+    g.fillOval(posX, posY, rad, rad);
+  }
+
+}
--- a/src/rendering/RectArtist.java
+++ b/src/rendering/RectArtist.java
@ -0,0 +1,33 @@
+package rendering;
+
+import gameobjects.GameObject;
+import java.awt.Color;
+import java.awt.Graphics2D;
+
+public class RectArtist extends Artist {
+
+  protected Color color;
+  protected double width, height;
+
+  public RectArtist(GameObject go, double width, double height, Color color) {
+    super(go);
+    this.color = color;
+    this.width = width;
+    this.height = height;
+  }
+
+  @Override
+  public void draw(Graphics2D g) {
+    g.setColor(this.color);
+
+    // g.drawLine((int) (Math.round(this.getX())), (int) (Math.round(this.getY()-this.height/2.)),
+    // (int) Math.round(this.getX()),
+    // (int) Math.round(this.getY() + this.height/2.));
+    int x = (int) this.getX();
+    int y = (int) this.getY();
+    g.fillRect((int) (this.getX() - this.width / 2.), (int) (this.getY() - this.height / 2.),
+        (int) this.width, (int) this.height);
+
+  }
+
+}
--- a/src/rendering/TextArtist.java
+++ b/src/rendering/TextArtist.java
@ -0,0 +1,81 @@
+package rendering;
+
+import gameobjects.GameObject;
+import java.awt.Color;
+import java.awt.Font;
+import java.awt.Graphics2D;
+import java.awt.font.FontRenderContext;
+import java.awt.font.TextAttribute;
+import java.text.AttributedString;
+
+/**
+ * Rendering an object as a text of a specified color, size and font.
+ */
+public class TextArtist extends Artist {
+
+  private String text = null;
+  private int size = 1;
+  private Color textColor = null;
+  protected double textWidth, textHeight;
+  Font serifFont = null;
+
+  public TextArtist(GameObject go, String text, int size, Color textColor) {
+    super(go);
+    this.size = size;
+    this.text = text;
+
+    this.serifFont = new Font("Serif", Font.PLAIN, size);
+    FontRenderContext frc = new FontRenderContext(null, false, false);
+    this.textWidth = (int) (serifFont.getStringBounds(text, frc).getWidth());
+    this.textHeight = (int) (serifFont.getStringBounds(text, frc).getHeight());
+
+    this.textColor = textColor;
+  }
+
+
+  public String getText() {
+    return this.text;
+  }
+
+  public void setText(String s) {
+    this.text = s;
+  }
+
+
+
+  public double getTextWidth() {
+    return textWidth;
+  }
+
+
+  public void setTextWidth(double textWidth) {
+    this.textWidth = textWidth;
+  }
+
+
+
+  public double getTextHeight() {
+    return textHeight;
+  }
+
+
+  public void setTextHeight(double textHeight) {
+    this.textHeight = textHeight;
+  }
+
+  /**
+   * Draw the text.
+   * 
+   * @param g The Swing graphics context.
+   */
+  @Override
+  public void draw(Graphics2D g) {
+    AttributedString as = new AttributedString(this.text);
+    as.addAttribute(TextAttribute.FONT, this.serifFont);
+    as.addAttribute(TextAttribute.FOREGROUND, this.textColor);
+
+    g.drawString(as.getIterator(), (int) Math.round(this.getX() - this.textWidth / 2.),
+        (int) Math.round(this.getY() + this.textHeight / 2.));
+  }
+
+}