Leikr Game System

A Game System for making games and programs in Groovy. (A Fantasy Console idea)

Why Groovy?

Groovy: If you describe something as groovy, you mean that it is attractive, fashionable, or exciting. https://www.collinsdictionary.com/dictionary/english/groovy

Apache Groovy is a powerful, optionally typed and dynamic language, with static-typing and static compilation capabilities, for the Java platform aimed at improving developer productivity thanks to a concise, familiar and easy to learn syntax. – http://groovy-lang.org/

Technologies

Once you’ve mastered Leikr and feel the need to expand into bigger waters, you can take your knowledge and move up to Mini2Dx itself.

Preview

Running from release

note: If downloading from itch.io, make sure to document where the install path is for accessing the files.

A release is a folder which contains everything required to run the Leikr Game System. Releases can be found from one of the distribution sources (Currently: flathub.org, itch.io or github)

Inside this folder should look something like this:

Leikr/
    Data/
    Programs/
    Leikr
    Leikr.bat
    Leikr.jar
    Sys/    

Depending on your system, you can either launch the system through the Leikr shell script or Leikr.bat. If you’d rather, You can even launch the system manually the java way using the command java -jar Leikr.jar

Running from source

notes: `Programs` and `Data` are in the `/leikr/assets/` directory. It is NOT recommended to run untrusted user programs from this method. Gradle currently does not apply the security sandbox policy.

`>` is the terminal icon, don’t type this.

Java is required to run this program. Best used with AdoptOpenJDK. Version 1.0.0 is tested with Java 15 at a minimum

git clone the project. Then enter the leikr directory.

> git clone https://github.com/torbuntu/leikr.git
> cd Leikr

Run the gradlew command:

>./gradlew launchDesktop

Building a release

to build a release:

>./gradlew clean build deployLeikr

the release will show up in the Leikr/deploy directory. You should end up with the following:

Data/
Programs/
Sys/
Leikr
Leikr.bat
Leikr.jar

Starting your own Program

From the Leikr terminal view, you can run either new GameName to quickly generated a project from an internal template, or you can run new and walk through a generator.

Projects structure

Data/
Sys/
Programs/
  YourGameName/
     /Art/
         icon.png
         city.png
     /Audio/
        /Sound/
            walk.wav
        /Music/
            theme.wav
            intro.wav
     /Code/ 
         YourGameName.groovy
     /Maps/
         overworld.tmx
         underworld.tmx
     /Sprites/
         Sprites.png
     program.properties

In order for your game to be runnable, the main class file should be similar to the following template:

// Extend the engine to get the API 
class MyGame extends leikr.Engine{

  void create(){
      //Initialize classes and variables here. Runs on first load.
  }
  
  void update(float delta){
      // Runs every frame. Used for updating variables and game state.
  }
  
  void render(){
      // Draws to the screen after update.
  }
}

note however that all three of the main methods (create, update and render) are optional. You can make smaller graphic demos just using the render method.

Specs:

Spec
Resolution	240x160
Sprites	128 max draw calls per frame. Sprites.png gets split into 8x8, 16x16, 32x32 and 64x64 pixel sprites.
Art	Can load images to be used as backgrounds or however else you wish.
Maps	.tmx maps loadabled from `Maps` directory. (Animated tiles are supported)
Audio	16bit .WAV, .OGG, or MP3 files loaded from `Audio/Sound` and `Audio/Music`
Controls	Primary: Keyboard, Mouse. Secondary: USB Controllers (snes layout). Tested using SNES style controllers on Linux. Note: The controllers are configurable using the Program `Controllers` which comes with the system. It maps inputs to the file `Data/system.properties`