transmute / core

The Transmute library

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Good places to start21 results
Getting startedInstall the engine and build your first game.GuidesArchitectureUnderstand the engine, managers, and game loop.GuidesExamplesStart with a working platformer, RPG, or hello world.GuidesHeadless testingVerify gameplay without opening a window.GuidesAPI overviewExplore the building blocks of the engine.APIGame lifecycleConfigure, initialize, update, and render your game.APIAssets and manifestsLoad sprites, fonts, and audio with GameSpec.APIWorlds and physicsBuild tile worlds, movement, and collision.APIHeadless harnessSimulate input and assert frames and audio.APIhello worldA hands-on walkthrough of hello world.Tutorialssprites and animationA hands-on walkthrough of sprites and animation.Tutorialsinput and movementA hands-on walkthrough of input and movement.Tutorialscollision detectionA hands-on walkthrough of collision detection.Tutorialsstate managementA hands-on walkthrough of state management.Tutorialsaudio systemA hands-on walkthrough of audio system.Tutorialslevel designA hands-on walkthrough of level design.TutorialsAuthoring gamesTurn a prompt and assets into a verified game.GuidesCookbookFind practical recipes for common game features.GuidesContributingSet up Flox and run the project checks.GuidesWebsite developmentDevelop, preview, and deploy this website.GuidesCLI distributionBuild and distribute the game scaffolding CLI.Guides
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Headless harness

GameHarness owns a game instance and advances a chosen number of frames. Use try-with-resources so the harness always closes.

Create a harness

GameConfig config = new GameConfig.Builder()
    .title("Test").version("0").size(320, 180).scale(1)
    .headless(true).showStartScreen(false).build();

try (GameHarness harness = GameHarness.of(() -> new MyGame(config))) {
    harness.step(1);
    FrameAssert.assertPixel(harness.renderer(), 0, 0, expectedArgb);
}

GameHarness and FrameAssert are in TransmuteCore.util.verify. MyGame and expectedArgb are supplied by your test.

Simulate input

SimulatedInput input = (SimulatedInput)
    harness.game().getManager().getInputHandler();
input.pressKey(KeyEvent.VK_SPACE);
harness.step(1);
input.releaseKey(KeyEvent.VK_SPACE);
harness.step(1);

SimulatedInput is in TransmuteCore.input; KeyEvent is in java.awt.event. Headless mode installs simulated input automatically. Release keys explicitly when testing transitions.

More assertions

Use AudioProbe to inspect requested sounds without requiring an audio device, and PlaytestScript for data-driven input sequences. See headless testing for the repository verification loop.

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