jrpg-stellar-engine
Version:
Retro JRPG browser game engine.
96 lines (75 loc) • 2.46 kB
JavaScript
/**
* AnimSprite - animated sprite
*/
class AnimSprite extends Sprite {
/**
* Create animated sprite
* All Sprite params plus:
* @param animations: Object - map of animations { animName: [{frame: nr, duration: ms}, ...], ... }
*/
constructor(args) {
super(args);
// Animation map
this.animations = 'animations' in args ? args.animations : {};
// Current animation state
this.anim = {
// Animation name
name: null,
// Frames list from this.animations
frames: null,
// Current frame counter
index: 0,
// Current time of the animation frame
time: 0,
// Start new anim
start: function(name, animation) {
this.name = name;
this.frames = animation;
this.index = 0;
this.time = 0;
},
// Play forward a little bit
advance: function(deltaTime, loop = true) {
this.time += deltaTime;
if (this.time * 1000 >= this.frames[this.index].duration) {
this.time = 0;
if (this.index < this.frames.length - 1) this.index ++;
else if (loop) this.index = 0;
}
},
// Get current tile index
frame: function() {
return this.frames ? this.frames[this.index].frame : 0;
}
};
}
/**
* Update animation
* @param name: string - name of the animation
* @param deltaTime: Number - time passed since last frame
* @param loop: bool - should be looped
*/
animate(name, deltaTime = 0, loop = true) {
if (this.anim.name != name) {
if (name in this.animations) this.anim.start(name, this.animations[name]);
else console.error(`Can't find animation '${name}' in the ${this.name}!`)
}
else {
this.anim.advance(deltaTime, loop);
}
}
/**
* Render animated sprite
*/
render(view) {
super.position(this.transform.x, this.transform.y);
super.cell(this.anim.frame());
super.render(view);
}
/**
* Update animated sprite with default animation
*/
update(args) {
if (this.anim.name) this.animate(this.anim.name, args.deltaTime);
}
}