KAPLAY v4000 Alpha 23

lajbel, 11/5/2025, from the inside of the Pumpka

Hey! lajbel here. Let me introduce you to the next version of KAPLAY, the alpha 23. Before getting into all the new features, let’s see how to install it:

npm install kaplay@4000.0.0-alpha.23

Lifetime Scopes

The first thing I would like to introduce is the Lifetime Scopes feature. Before, it was impossible to have event handlers that wouldn’t be destroyed in scene change, now it is! There are three scopes:

app: These event handlers are not canceled automatically.
scene: These event handlers are canceled on scene change. (Note that now you can access scene as an object, also still use scene())
obj: These event handlers need to be used with an object (obj = add([])) and them are canceled on object destroy

The list of supported handlers is in the type GameEventHandlers.

Let’s see this quick example:

kaplay({
    defaultLifetimeScope: "scene", // "scene" is default
});

loadBean();

app.onKeyPress("a", () => {
    debug.log("I run until cancelled");
});

scene("bean", () => {
    const obj = add([sprite("bean")]);

    obj.onKeyPress("o", () => {
        debug.log("I run until obj get destroyed");
        obj.destroy();
    });

    scene.onKeyPress("s", () => { // or just onUpdate(() => {
        debug.log("I run until scene is changed", "current scene is bean");
        go("rice");
    });
});

scene("rice", () => {
    scene.onKeyPress("s", () => { // or just onUpdate(() => {
        debug.log("I run until scene is changed", "current scene is rice");
    });
});

go("bean");

More explanations will come in a future guide, as it is a quite big feature.

The skew property in Text Transformation

Now in the Text Transformation API (TextCompOpt.styles) you can use the skew property, let’s see an example creating text italics:

kaplay({
    background: "black"
});

add([
    pos(100, 100),
    text(
        "oh [i]hi[/i]", {
            styles: {
                i: {
                    skew: 20,
                },
            },
        },
    ),
]);

Little perfomance improvements

If you were using maxFps you might get better perfomance with this version thanks to some bug fixes related to this.

So, that’s all for this version, next version will include UI and Hover Refactor, we’ll talk more about it in the next release. Thank you, I leave you with the changelog.

[4000.0.0-alpha.23] - 2025-11-05

Added

Added getGamepadAnalogButton() to read the analog value of buttons like the triggers - @dragoncoder047

isGamepadButtonDown("rtrigger"); // -> true/false, 0/1
getGamepadAnalogButton("rtrigger"); // -> analog value between 0 (not pressed) and 1 (fully pressed)

Added chorded button bindings using the Buttons API, so you can bind different actions to tab and shift+tab, and handle them like normal. Also works with gamepads and mouse! - @dragoncoder047

kaplay({
    buttons: {
        forward: {
            keyboard: "tab",
            gamepad: "south",
        },
        backward: {
            keyboard: "shift+tab",
            gamepad: "rshoulder+south",
        },
    },
});

Added skew to text formatting, so now italics is possible - @dragoncoder047
Added lifetime scopes, a way to define the lifetime of an event handler using a specific scope, scene, app or a game object - @lajbel, @dragoncoder047
```
app.onUpdate(() => {
    // runs until it is cancelled
});

scene("game", () => {
    const obj = add([]);

    obj.onUpdate(() => {
        // runs until obj is destroyed
    });

    scene.onUpdate(() => { // or just onUpdate(() => {
        // runs until scene is changed
    });
});
```
All the available handlers in the scopes are GameEventHandlers ones:
- onKeyDown()
- onKeyPress()
- onKeyPressRepeat()
- onKeyRelease()
- onCharInput()
- onMouseDown()
- onMousePress()
- onMouseRelease()
- onMouseMove()
- onScroll()
- onTouchStart()
- onTouchMove()
- onTouchEnd()
- onGamepadConnect()
- onGamepadDisconnect()
- onGamepadButtonDown()
- onGamepadButtonPress()
- onGamepadButtonRelease()
- onGamepadStick()
- onButtonDown()
- onButtonPress()
- onButtonRelease()
- onTabHide()
- onTabShow()
And this game object handlers may differ when using it with obj and scene/app:
- onFixedUpdate()
- onUpdate()
- onDraw()

Added app scope for app event handlers - @lajbel

app.onUpdate(() => {
    // runs until it is cancelled
});

Added KAPLAYOpt.defaultLifetimeScope for setting the default lifetime scope used for event handlers - @lajbel

kaplay({
    defaultLifetimeScope: "app", // default is "scene"
});

onKeyPress("space", () => {
    // runs until is cancelled
});

Added skew to text formatting, so now italics is possible - @dragoncoder047

Changed

(!) Renamed onShow() to onTabShow() and onHide() to onTabHide() - @lajbel

In addition to being the scene() function, now scene is also a scope for scene event handlers - @lajbel

scene("game", () => {
    scene.onUpdate(() => { // or just onUpdate(() => {
        // runs until scene is changed
    });
});

Fixed

Now pushScene() and popScene() give the arguments to the scene in the same way that go() does rather than passing them all to the first argument as an array - @dragoncoder047
Fixed a flicker due to the fadeIn not setting opacity until the next frame - @mflerackers
Fixed FPS cap not working correctly - @mflerackers, @dragoncoder047