esengine/source/src/ECS/Components/TiledSpriteRenderer.ts

///<reference path="./SpriteRenderer.ts" />
module es {
    /**
     * 滚动由两张图片组合而成
     */
    export class TiledSpriteRenderer extends SpriteRenderer {
        protected sourceRect: Rectangle;
        protected leftTexture: egret.Bitmap;
        protected rightTexture: egret.Bitmap;

        constructor(sprite: Sprite) {
            super(sprite);

            this.leftTexture = new egret.Bitmap();
            this.rightTexture = new egret.Bitmap();
            this.leftTexture.texture = sprite.texture2D;
            this.rightTexture.texture = sprite.texture2D;

            this.setSprite(sprite);
            this.sourceRect = sprite.sourceRect;
        }

        public get scrollX() {
            return this.sourceRect.x;
        }

        public set scrollX(value: number) {
            this.sourceRect.x = value;
        }

        public get scrollY() {
            return this.sourceRect.y;
        }

        public set scrollY(value: number) {
            this.sourceRect.y = value;
        }

        public render(camera: es.Camera) {
            if (!this.sprite)
                return;

            super.render(camera);

            let renderTexture = new egret.RenderTexture();
            let cacheBitmap = new egret.DisplayObjectContainer();
            cacheBitmap.removeChildren();
            cacheBitmap.addChild(this.leftTexture);
            cacheBitmap.addChild(this.rightTexture);

            this.leftTexture.x = this.sourceRect.x;
            this.rightTexture.x = this.sourceRect.x - this.sourceRect.width;
            this.leftTexture.y = this.sourceRect.y;
            this.rightTexture.y = this.sourceRect.y;

            cacheBitmap.cacheAsBitmap = true;
            renderTexture.drawToTexture(cacheBitmap, new egret.Rectangle(0, 0, this.sourceRect.width, this.sourceRect.height));
        }
    }
}