game-engine/modules/game-objects/player.js

118 lines
2.9 KiB
JavaScript

import { GAME_HEIGHT, GAME_WIDTH, TILE_SIZE } from "../constants.js";
import { GameObject } from "./game-object.js";
export class Sprite extends GameObject {
constructor({ image, x = 0, y = 0, width = 0, height = 0 }) {
super({ x, y, height, width });
this.image = image;
this.imageWidth = this.image.width;
this.imageHeight = this.image.height;
}
render(ctx, sourceX, sourceY) {
ctx.drawImage(
this.image,
this.x,
this.y,
this.width,
this.height,
sourceX,
sourceY,
this.width,
this.height
);
}
}
export class SpriteSheet extends GameObject {
constructor({
imageId,
x = 0,
y = 0,
tileWidth = 16,
tileHeight = 16,
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;
this.sprites = this._getSprites();
}
_getSprites() {
const sprites = [];
for (let row = 0; row < this.imageHeight; row += this.tileHeight) {
for (let col = 0; col < this.imageWidth; col += this.tileHeight) {
sprites.push(
new Sprite({
image: this.image,
x: col + this.offsetX,
y: row + this.offsetY,
width: this.tileWidth,
height: this.tileHeight,
})
);
}
}
return sprites;
}
}
export class Player extends GameObject {
constructor({ gameObjects = [], x = 0, y = 0, speed = 1, ...args }) {
super({ x, y, gameObjects, ...args });
this.speed = speed;
this.keys = [
{ key: "ArrowUp", pressed: false, value: [0, -1] },
{ key: "ArrowDown", pressed: false, value: [0, 1] },
{ key: "ArrowLeft", pressed: false, value: [-1, 0] },
{ key: "ArrowRight", pressed: false, value: [1, 0] },
];
this.availableKeys = this.keys.reduce(
(acc, item) => ({ ...acc, [item.key]: item }),
{}
);
this.eventEmitter.on("levelChanged", (...args) => {
this.x = x;
this.y = y;
});
}
update(delta) {
this.keys.forEach((item) => {
if (item.pressed) {
this.moveCharacter(...item.value, delta);
}
});
}
onKeyPressed(key) {
if (!this.availableKeys[key]) return;
this.availableKeys[key].pressed = true;
}
onKeyReleased(key) {
if (!this.availableKeys[key]) return;
this.availableKeys[key].pressed = false;
}
render(ctx, ...args) {
const [x, y] = args;
const [spriteSheet] = this.gameObjects;
const [item] = spriteSheet.sprites;
item.render(ctx, this.x - x, this.y - y);
}
moveCharacter(dx, dy, delta) {
const speed = Math.floor(delta * this.speed * 100);
this.x = this.x + dx * speed;
this.y = this.y + dy * speed;
// TODO: Check for collisions and stop movement if needed
}
}