starling-framework/lib/starling/filters/IFilterHelper.d.ts

A fast, productive library for 2D cross-platform development.

import DisplayObject from "./../display/DisplayObject";
import Texture from "./../textures/Texture";
import Rectangle from "openfl/geom/Rectangle";

declare namespace starling.filters
{
	/** An interface describing the methods available on the <code>helper</code> object passed
	 *  to the <code>process</code> call of fragment filters. It provides information about the
	 *  target object and methods to acquire and release pass textures.
	 *
	 *  @see FragmentFilter#process()
	 */
	export class IFilterHelper
	{
		/** Gets a pass texture from the pool, or creates a new one (cleared and ready to be used
		 *  as render target). Its size is dictated by the bounds of the target display object
		 *  plus padding.
		 *
		 *  <p>Beware: each call of this method counts as one render pass. For performance reasons,
		 *  the filter may be configured to render the last pass directly to the back buffer. In
		 *  that case, this method will return <code>null</code> for the last pass! That's the
		 *  sign for the <code>process</code> method to draw to the back buffer. If you receive
		 *  <code>null</code> too soon, the filter class probably didn't correctly override
		 *  <code>numPasses</code>.</p>
		 */
		getTexture(resolution?:number):Texture;
	
		/** Puts a texture back into the pool to be reused later (or to be disposed
		 *  with the pool). */
		putTexture(texture:Texture):void;
	
		/** The bounds of the target object (plus padding) in stage coordinates. */
		readonly targetBounds:Rectangle;
	
		/** The display object the filter is currently attached to. */
		readonly target:DisplayObject;
	}
}

export default starling.filters.IFilterHelper;