game-engine/modules/game-objects/sprite-sheet.js

49 lines
1.2 KiB
JavaScript

import { TILE_SIZE } from "../constants.js";
import { GameObject } from "./game-object.js";
import { Sprite } from "./sprite.js";
export class SpriteSheet extends GameObject {
constructor({
imageId,
x = 0,
y = 0,
tileWidth = TILE_SIZE,
tileHeight = TILE_SIZE,
offsetX = 0,
offsetY = 0,
}) {
super({ x, y });
this.image = document.getElementById(imageId);
this.imageWidth = this.image.width;
this.imageHeight = this.image.height;
this.tileWidth = tileWidth;
this.tileHeight = tileHeight;
this.offsetX = offsetX;
this.offsetY = offsetY;
}
get sprites() {
if (this.gameObjects?.length) {
return this.gameObjects;
}
const sprites = [];
let index = 0;
for (let row = 0; row < this.imageHeight; row += this.tileHeight) {
for (let col = 0; col < this.imageWidth; col += this.tileWidth) {
sprites.push(
new Sprite({
image: this.image,
index,
x: col + this.offsetX,
y: row + this.offsetY,
width: this.tileWidth,
height: this.tileHeight,
})
);
index++;
}
}
return (this.gameObjects = sprites);
}
}