BlitterRenderState.ts

    export class BlitterRenderState implements core.IPreRenderState {
        constructor(public cache: RuntimeCache) {
        }

        visit(node: Node) {
            const vs = node.rendererObject as pixi.VectorSprite;
            if (vs && vs.model) {
                //  && vs.model.preferredCache === pixi.CacheType.RuntimeWebGL ?
                this.cache.foundVectors.push(vs);
            }
        }

        screenStack: Array<core.Rectangle> = [new core.Rectangle()];
        prStack: Array<PreRenderStackElement> = [new PreRenderStackElement()];
        preRenderId = 0;
        prNum = 0;

        start(screen: core.Rectangle) {
			this.screenStack[0].copyFrom(screen);
			this.prNum = 0;
			this.prStack[0].reset();
		}

        pushFilters(target: pixi.systems.FilterTarget, filters: Array<pixi.Filter>) {
            this.screenStack.push(target.filterArea);
            this.prNum++;
            while (!this.prStack[this.prNum]) {
            	this.prStack.push(new PreRenderStackElement());
			}
            this.prStack[this.prNum].reset();
        }

        popFilters() {
            this.screenStack.pop();
            this.prNum--;
        }

        get sourceFrame() {
            return this.screenStack[this.screenStack.length - 1];
        }

        get current() {
        	return this.prStack[this.prNum];
		}
    }

    export class PreRenderStackElement {
		snapFlags = 0;
		renderObjectsNum = 0;
		multiplyBlendMode = 2;
		maskBalance = 0;

		reset() {
			this.snapFlags = 0;
			this.renderObjectsNum = 0;
			this.multiplyBlendMode = 2;
			this.maskBalance = 0;
		}
	}