Migration guide for ct.js v4.0.

Ct.js lost its ct.! 🙀

All the ct.something lines are now just something, with few exceptions:

• ct.sound is now sounds, in plural form.
  • ct.sound.spawn is now sounds.play
  • Some options and methods may be different; see the new sounds docs.
• ct.delta is now u.delta, ct.deltaUi is u.deltaUi.
• ct.room is now rooms.current.
• ct.pixiApp is now just pixiApp.
• ct.roomWidth and ct.roomHeight are now rooms.current.viewWidth and rooms.current.viewHeight.
• ct.speed is now settings.targetFps.

Example. Old code:

// A snippet from the catsteroids demo
this.targetx = ct.random.range(75, ct.camera.width - 75);
this.targety = ct.random.range(75, 300);
ct.tween.add({
    obj: this,
    fields: {
        x: this.targetx,
        y: this.targety
    },
    duration: 1500
});

New code:

// A snippet from the catsteroids demo
this.targetx = random.range(75, camera.width - 75);
this.targety = random.range(75, 300);
tween.add({
    obj: this,
    fields: {
        x: this.targetx,
        y: this.targety
    },
    duration: 1500
});

camera is not writable now

You can't assign a new camera to the camera variable.

New values for tracking time and changes in this.move() and backgrounds

Aside from u.delta and u.deltaUi, ct.js now also has u.time and u.timeUi, which are computed in secods and show the time passed between the last frame and the current one. It is recommended that you use these values for velocity and other time-dependent variables instead of u.delta and u.deltaUi, as the latter two won't provide smooth movement if you change the framerate cap in-game.

• Due to that, this.move() method now uses these values as well, and you will need to multiply your speed values by your Max FPS number you've defined in project's rendering settings. (Defaults to 60.)

• This also affects place.moveSmart and place.moveBullet, as well as backgrounds' movement speed.

• With acceleration values like those in this.gravity and this.addSpeed, you will need to multiply these with your max framerate twice (which is 3600 with default framerate), because physics.

• u.delta and u.deltaUi are now deprecated, though still available for use.

FitToScreen catmod is now a part of ct.js core library

Viewport settings are moved to project's render settings. Moreover, you can change viewport settings on the fly in the game with the new settings API!

Skeletal animations are no longer supported

Ct.js updated its underlying graphics library pixi.js, and though it brought various benefits for development and rendering performance, the DragonBones runtime is no longer supported by it, thus the skeletal animations are no longer supported in ct.js. Ct.js will probably add support for another runtime if its license is MIT-compatible.

Pixi.js was updated from v5.3 to v7.1

This includes some breaking changes and deprecations from the underlying graphics library. Unless you are using pixi.js API directly, this should not affect your projects.

Catmods

The option useUiDelta in tween.add was renamed to be isUi to match how other ct.js code names similar options.

The /*!%start%*/ injection was removed. Instead, write code in the index.js file.

Catmods mouse and touch were removed. Use pointer module instead, or the built-in pointer events you can add to event lists of your templates.

ct.u.ext (aka ct.u.extend) were removed

Use Object.assign(target, valuesObject) instead — it works the same.