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starling-framework

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

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import SubTexture from "./SubTexture"; import DisplayObject from "../display/DisplayObject"; import Vector3D from "openfl/geom/Vector3D"; import Matrix from "openfl/geom/Matrix"; declare namespace starling.textures { /** * A RenderTexture is a dynamic texture onto which you can draw any display object. * * * * <p>After creating a render texture, just call the <code>draw</code> method to render * * an object directly onto the texture. The object will be drawn onto the texture at its current * * position, adhering its current rotation, scale and alpha properties.</p> * * * * <p>Drawing is done very efficiently, as it is happening directly in graphics memory. After * * you have drawn objects onto the texture, the performance will be just like that of a normal * * texture — no matter how many objects you have drawn.</p> * * * * <p>If you draw lots of objects at once, it is recommended to bundle the drawing calls in * * a block via the <code>drawBundled</code> method, like shown below. That will speed it up * * immensely, allowing you to draw hundreds of objects very quickly.</p> * * * * <pre> * * renderTexture.drawBundled(function():void * * { * * for (var i:int=0; i&lt;numDrawings; ++i) * * { * * image.rotation = (2 &#42; Math.PI / numDrawings) &#42; i; * * renderTexture.draw(image); * * } * * }); * * </pre> * * * * <p>To erase parts of a render texture, you can use any display object like a "rubber" by * * setting its blending mode to <code>BlendMode.ERASE</code>. To wipe it completely clean, * * use the <code>clear</code> method.</p> * * * * <strong>Persistence</strong> * * * * <p>Older devices may require double buffering to support persistent render textures. Thus, * * you should disable the <code>persistent</code> parameter in the constructor if you only * * need to make one draw operation on the texture. The static <code>useDoubleBuffering</code> * * property allows you to customize if new textures will be created with or without double * * buffering.</p> * * * * <strong>Context Loss</strong> * * * * <p>Unfortunately, render textures are wiped clean when the render context is lost. * * This means that you need to manually recreate all their contents in such a case. * * One way to do that is by using the <code>root.onRestore</code> callback, like here:</p> * * * * <listing> * * renderTexture.root.onRestore = function():void * * { * * var quad:Quad = new Quad(100, 100, 0xff00ff); * * renderTexture.clear(); // required on texture restoration * * renderTexture.draw(quad); * * });</listing> * * * * <p>For example, a drawing app would need to store information about all draw operations * * when they occur, and then recreate them inside <code>onRestore</code> on a context loss * * (preferably using <code>drawBundled</code> instead).</p> * * * * <p>However, there is one problem: when that callback is executed, it's very likely that * * not all of your textures are already available, since they need to be restored, too (and * * that might take a while). You probably loaded your textures with the "AssetManager". * * In that case, you can listen to its <code>TEXTURES_RESTORED</code> event instead:</p> * * * * <listing> * * assetManager.addEventListener(Event.TEXTURES_RESTORED, function():void * * { * * var brush:Image = new Image(assetManager.getTexture("brush")); * * renderTexture.draw(brush); * * });</listing> * * * * <p>[Note that this time, there is no need to call <code>clear</code>, because that's the * * default behavior of <code>onRestore</code>, anyway — and we didn't modify that.]</p> * * * */ export class RenderTexture extends SubTexture { /** * Creates a new RenderTexture with a certain size (in points). If the texture is * * persistent, its contents remains intact after each draw call, allowing you to use the * * texture just like a canvas. If it is not, it will be cleared before each draw call. * * * * <p>Non-persistent textures can be used more efficiently on older devices; on modern * * hardware, it does not make a difference. For more information, have a look at the * * documentation of the <code>useDoubleBuffering</code> property.</p> * */ constructor(width: number, height: number, persistent?: boolean, scale?: number, format?: string, forcePotTexture?: boolean); /** * Indicates if new persistent textures should use double buffering. Single buffering * * is faster and requires less memory, but is not supported on all hardware. * * * * <p>By default, applications running with the profile "baseline" or "baselineConstrained" * * will use double buffering; all others use just a single buffer. You can override this * * behavior, though, by assigning a different value at runtime.</p> * * * * @default true for "baseline" and "baselineConstrained", false otherwise * */ static get useDoubleBuffering(): boolean; static set useDoubleBuffering(value: boolean) /** * @inheritDoc */ override dispose(): void; /** * Draws an object into the texture. * * * * @param object The object to draw. * * @param matrix If 'matrix' is null, the object will be drawn adhering its * * properties for position, scale, and rotation. If it is not null, * * the object will be drawn in the orientation depicted by the matrix. * * @param alpha The object's alpha value will be multiplied with this value. * * @param antiAliasing Values range from 0 (no antialiasing) to 4 (best quality). * * Beginning with AIR 22, this feature is supported on all platforms * * (except for software rendering mode). * * @param cameraPos When drawing a 3D object, you can optionally pass in a custom * * camera position. If left empty, the camera will be placed with * * its default settings (centered over the texture, fov = 1.0). * */ draw(object: DisplayObject, matrix?: Matrix, alpha?: number, antiAliasing?: number, cameraPos?: Vector3D): void; /** * Bundles several calls to <code>draw</code> together in a block. This avoids buffer * * switches and allows you to draw multiple objects into a non-persistent texture. * * Note that the 'antiAliasing' setting provided here overrides those provided in * * individual 'draw' calls. * * * * @param drawingBlock a callback with the form: <pre>function():void;</pre> * * @param antiAliasing Values range from 0 (no antialiasing) to 4 (best quality). * * Beginning with AIR 22, this feature is supported on all platforms * * (except for software rendering mode). * * @param cameraPos When drawing a 3D object, you can optionally pass in a custom * * camera position. If left empty, the camera will be placed with * * its default settings (centered over the texture, fov = 1.0). * */ drawBundled(drawingBlock: () => void, antiAliasing?: number, cameraPos?: Vector3D): void; /** * Clears the render texture with a certain color and alpha value. Call without any * * arguments to restore full transparency. */ clear(color?: number, alpha?: number): void; /** * Indicates if the texture is persistent over multiple draw calls. */ get isPersistent(): boolean; } } export default starling.textures.RenderTexture;