JLud2D

JLud2D is an old-school engine for games, currently in Java 8. It is compatible with Tiled maps, RPG-style characters and sprites, and MP3, MIDI, VGM, S3M, MOD and XM music formats.

Overview

The engine provides useful classes and methods for rapid development.

Below is an example of switching from a map to another one:

	void exit() {
		mapswitch(Planet.PALMA, 84, 49);		
	}

Here is an example of a map script used when talking with an entity:

 void robot() {
		EntStart();
		PSMenu.Stext("You are trespassing. Go back!"));
		EntFinish();
	}

List of Features

• 2D Engine;
• Multi-plataform;
• Tiled support (JSON format), a free, easy to use and flexible tile map editor;
• You could run and debug the game code in some advanced IDE like Eclipse or Netbeans;
• Music formats: MP3, MIDI, VGM, S3M, MOD and XM;
• Sound formats: WAV, VOC and MP3;
• Graphic formats: PNG, JPG, GIF, PCX and others - basically all you can load using Java;
• Easy-to-use API;
• Suitable for 2D board games, RPG games, platform games and many more.

Getting Started: I want to play

Running Pre-built JARs (Original Method)

You can download just the demo / game you want to play and execute it with Java 8 command line:

java -jar Demo.jar

They are located in the /redist folder.

Running from Source (Updated Method)

Prerequisites:

• Maven installed
• Java 8+ (tested with Java 21)

Build the project:

mvn clean compile

Copy demo assets to classpath:

# For Demo1 (Island World)
mkdir -p target/classes/demos/demo1 && cp src/demos/demo1/* target/classes/demos/demo1/

# For Demo2 (Golden Warrior)
mkdir -p target/classes/demos/demo2 && cp src/demos/demo2/* target/classes/demos/demo2/

# For Alex Kidd Demo
mkdir -p target/classes/demos/ak && cp -r src/demos/ak/* target/classes/demos/ak/

# For Phantasy Star Demo
mkdir -p target/classes/demos/ps && cp -r src/demos/ps/* target/classes/demos/ps/

Run demos with proper Java module access:

# Demo1 - Island World
MAVEN_OPTS="--add-opens java.desktop/java.awt.image=ALL-UNNAMED --add-opens java.desktop/java.awt.color=ALL-UNNAMED --add-opens java.desktop/java.awt=ALL-UNNAMED --add-opens java.desktop/sun.java2d=ALL-UNNAMED --add-opens java.desktop/sun.awt.image=ALL-UNNAMED --add-opens java.base/java.lang=ALL-UNNAMED --add-opens java.base/java.lang.reflect=ALL-UNNAMED" mvn exec:java -Dexec.mainClass="demos.demo1.Demo1"

# Demo2 - Golden Warrior
MAVEN_OPTS="--add-opens java.desktop/java.awt.image=ALL-UNNAMED --add-opens java.desktop/java.awt.color=ALL-UNNAMED --add-opens java.desktop/java.awt=ALL-UNNAMED --add-opens java.desktop/sun.java2d=ALL-UNNAMED --add-opens java.desktop/sun.awt.image=ALL-UNNAMED --add-opens java.base/java.lang=ALL-UNNAMED --add-opens java.base/java.lang.reflect=ALL-UNNAMED" mvn exec:java -Dexec.mainClass="demos.demo2.Demo2"

# Alex Kidd Demo
MAVEN_OPTS="--add-opens java.desktop/java.awt.image=ALL-UNNAMED --add-opens java.desktop/java.awt.color=ALL-UNNAMED --add-opens java.desktop/java.awt=ALL-UNNAMED --add-opens java.desktop/sun.java2d=ALL-UNNAMED --add-opens java.desktop/sun.awt.image=ALL-UNNAMED --add-opens java.base/java.lang=ALL-UNNAMED --add-opens java.base/java.lang.reflect=ALL-UNNAMED" mvn exec:java -Dexec.mainClass="demos.ak.AK"

# Phantasy Star Demo
MAVEN_OPTS="--add-opens java.desktop/java.awt.image=ALL-UNNAMED --add-opens java.desktop/java.awt.color=ALL-UNNAMED --add-opens java.desktop/java.awt=ALL-UNNAMED --add-opens java.desktop/sun.java2d=ALL-UNNAMED --add-opens java.desktop/sun.awt.image=ALL-UNNAMED --add-opens java.base/java.lang=ALL-UNNAMED --add-opens java.base/java.lang.reflect=ALL-UNNAMED" mvn exec:java -Dexec.mainClass="demos.ps.Phantasy"

Note: The --add-opens flags are required for Java 9+ to allow the older Gson library to access private fields via reflection.

Game Controls:

• F5 for sound off/on
• F6 for full screen
• F7/F8 to increase/decrease frame delay.

Getting Started: I want to develop

JLud2D uses Maven as a Dependency Management system. An intermediate to experienced Java developer should have no problem working with the repository. Feel free to fork it and contribute.

Tips

• Jar files are case-sensitive, so be sure to check when looking for resources inside it: sounds, maps, animations, images, etc
• Develop always with internationalization in mind. Internationalization Links: http://java.sun.com/developer/technicalArticles/Intl/ResourceBundles and http://www.roseindia.net/java/example/java/swing/internationalization.shtml

Planned features:

• Caching for fast loading
• Implement music volume
• Joystick support
• Socket implementation
• Movie playback implementation
• LUA parser for easy scripting
• Mobile support
• Check 3D API with fixed-z (~2D) to enable Video optimization

Bugs and Updates:

• Check VGM loops (right now they aren't looping)
• VGMs don't play, just VGZ.
• Implement key mapping (b1,b2,b3,b4)
• Verify ColorFilter, Implement Rotate, Flip, etc (See Graphics2d Rotate, Scale, etc)
• Make it more OO (less static methods, no public properties, no static imports)
• Entities' movement get screwed after talking to them
• Investigate why sometimes the transparency stops working (when swapping window/full screen)