CloudInvaders/js/entity.js

class Entity {
    constructor(x, y, w, h) {
        this.x = x;
        this.y = y;
        this.w = w;
        this.h = h;
        this.element = document.createElement('div');
        this.alive = true;
    }

    getScreenCoords() {
        return {
            x: (this.x - this.w / 2) * CANVAS.width,
            y: (this.y - this.h / 2) * CANVAS.height,
            w: this.w * CANVAS.width,
            h: this.h * CANVAS.height,
        }
    }

    draw() {
        if (this.alive) {
            const { x, y, w, h } = this.getScreenCoords();

            if (this.image) {
                CTX.drawImage(this.image, x, y, w, h);
            } else {
                CTX.fillStyle = this.color ?? 'red';
                CTX.fillRect(x, y, w, h);
            }
        }
    }

    destroy() {
        this.alive = false;
    }

    isOverlapped(other) {
        if (!this.alive || !other.alive) return false;
        if (other.x + other.w / 2 < this.x - this.w / 2) return false;
        if (other.x - other.w / 2 > this.x + this.w / 2) return false;
        if (other.y + other.h / 2 < this.y - this.h / 2) return false;
        if (other.y - other.h / 2 > this.y + this.h / 2) return false;

        return true;
    }
}