import { RenderTexture } from '@pixi/core';
import { CanvasRenderTarget } from '@pixi/utils';
import { Rectangle } from '@pixi/math';
const TEMP_RECT = new Rectangle();
const BYTES_PER_PIXEL = 4;
/**
* This class provides renderer-specific plugins for exporting content from a renderer.
* For instance, these plugins can be used for saving an Image, Canvas element or for exporting the raw image data (pixels).
*
* Do not instantiate these plugins directly. It is available from the `renderer.plugins` property.
* See {@link PIXI.CanvasRenderer#plugins} or {@link PIXI.Renderer#plugins}.
* @example
* // Create a new app (will auto-add extract plugin to renderer)
* const app = new PIXI.Application();
*
* // Draw a red circle
* const graphics = new PIXI.Graphics()
* .beginFill(0xFF0000)
* .drawCircle(0, 0, 50);
*
* // Render the graphics as an HTMLImageElement
* const image = app.renderer.plugins.extract.image(graphics);
* document.body.appendChild(image);
* @class
* @memberof PIXI
*/
export class Extract
{
/**
* @param {PIXI.Renderer} renderer - A reference to the current renderer
*/
constructor(renderer)
{
this.renderer = renderer;
/**
* Collection of methods for extracting data (image, pixels, etc.) from a display object or render texture
*
* @member {PIXI.Extract} extract
* @memberof PIXI.Renderer#
* @see PIXI.Extract
*/
renderer.extract = this;
}
/**
* Will return a HTML Image of the target
*
* @param {PIXI.DisplayObject|PIXI.RenderTexture} target - A displayObject or renderTexture
* to convert. If left empty will use the main renderer
* @param {string} [format] - Image format, e.g. "image/jpeg" or "image/webp".
* @param {number} [quality] - JPEG or Webp compression from 0 to 1. Default is 0.92.
* @return {HTMLImageElement} HTML Image of the target
*/
image(target, format, quality)
{
const image = new Image();
image.src = this.base64(target, format, quality);
return image;
}
/**
* Will return a a base64 encoded string of this target. It works by calling
* `Extract.getCanvas` and then running toDataURL on that.
*
* @param {PIXI.DisplayObject|PIXI.RenderTexture} target - A displayObject or renderTexture
* to convert. If left empty will use the main renderer
* @param {string} [format] - Image format, e.g. "image/jpeg" or "image/webp".
* @param {number} [quality] - JPEG or Webp compression from 0 to 1. Default is 0.92.
* @return {string} A base64 encoded string of the texture.
*/
base64(target, format, quality)
{
return this.canvas(target).toDataURL(format, quality);
}
/**
* Creates a Canvas element, renders this target to it and then returns it.
*
* @param {PIXI.DisplayObject|PIXI.RenderTexture} target - A displayObject or renderTexture
* to convert. If left empty will use the main renderer
* @return {HTMLCanvasElement} A Canvas element with the texture rendered on.
*/
canvas(target)
{
const renderer = this.renderer;
let resolution;
let frame;
let flipY = false;
let renderTexture;
let generated = false;
if (target)
{
if (target instanceof RenderTexture)
{
renderTexture = target;
}
else
{
renderTexture = this.renderer.generateTexture(target);
generated = true;
}
}
if (renderTexture)
{
resolution = renderTexture.baseTexture.resolution;
frame = renderTexture.frame;
flipY = false;
renderer.renderTexture.bind(renderTexture);
}
else
{
resolution = this.renderer.resolution;
flipY = true;
frame = TEMP_RECT;
frame.width = this.renderer.width;
frame.height = this.renderer.height;
renderer.renderTexture.bind(null);
}
const width = Math.floor((frame.width * resolution) + 1e-4);
const height = Math.floor((frame.height * resolution) + 1e-4);
let canvasBuffer = new CanvasRenderTarget(width, height, 1);
const webglPixels = new Uint8Array(BYTES_PER_PIXEL * width * height);
// read pixels to the array
const gl = renderer.gl;
gl.readPixels(frame.x * resolution, frame.y * resolution, width, height, gl.RGBA, gl.UNSIGNED_BYTE, webglPixels);
// add the pixels to the canvas
const canvasData = canvasBuffer.context.getImageData(0, 0, width, height);
Extract.arrayPostDivide(webglPixels, canvasData.data);
canvasBuffer.context.putImageData(canvasData, 0, 0);
// pulling pixels
if (flipY)
{
const target = new CanvasRenderTarget(canvasBuffer.width, canvasBuffer.height, 1);
target.context.scale(1, -1);
// we can't render to itself because we should be empty before render.
target.context.drawImage(canvasBuffer.canvas, 0, -height);
canvasBuffer.destroy();
canvasBuffer = target;
}
if (generated)
{
renderTexture.destroy(true);
}
// send the canvas back..
return canvasBuffer.canvas;
}
/**
* Will return a one-dimensional array containing the pixel data of the entire texture in RGBA
* order, with integer values between 0 and 255 (included).
*
* @param {PIXI.DisplayObject|PIXI.RenderTexture} target - A displayObject or renderTexture
* to convert. If left empty will use the main renderer
* @return {Uint8Array} One-dimensional array containing the pixel data of the entire texture
*/
pixels(target)
{
const renderer = this.renderer;
let resolution;
let frame;
let renderTexture;
let generated = false;
if (target)
{
if (target instanceof RenderTexture)
{
renderTexture = target;
}
else
{
renderTexture = this.renderer.generateTexture(target);
generated = true;
}
}
if (renderTexture)
{
resolution = renderTexture.baseTexture.resolution;
frame = renderTexture.frame;
// bind the buffer
renderer.renderTexture.bind(renderTexture);
}
else
{
resolution = renderer.resolution;
frame = TEMP_RECT;
frame.width = renderer.width;
frame.height = renderer.height;
renderer.renderTexture.bind(null);
}
const width = frame.width * resolution;
const height = frame.height * resolution;
const webglPixels = new Uint8Array(BYTES_PER_PIXEL * width * height);
// read pixels to the array
const gl = renderer.gl;
gl.readPixels(frame.x * resolution, frame.y * resolution, width, height, gl.RGBA, gl.UNSIGNED_BYTE, webglPixels);
if (generated)
{
renderTexture.destroy(true);
}
Extract.arrayPostDivide(webglPixels, webglPixels);
return webglPixels;
}
/**
* Destroys the extract
*
*/
destroy()
{
this.renderer.extract = null;
this.renderer = null;
}
/**
* Takes premultiplied pixel data and produces regular pixel data
*
* @private
* @param pixels {number[] | Uint8Array | Uint8ClampedArray} array of pixel data
* @param out {number[] | Uint8Array | Uint8ClampedArray} output array
*/
static arrayPostDivide(pixels, out)
{
for (let i = 0; i < pixels.length; i += 4)
{
const alpha = out[i + 3] = pixels[i + 3];
if (alpha !== 0)
{
out[i] = Math.round(Math.min(pixels[i] * 255.0 / alpha, 255.0));
out[i + 1] = Math.round(Math.min(pixels[i + 1] * 255.0 / alpha, 255.0));
out[i + 2] = Math.round(Math.min(pixels[i + 2] * 255.0 / alpha, 255.0));
}
else
{
out[i] = pixels[i];
out[i + 1] = pixels[i + 1];
out[i + 2] = pixels[i + 2];
}
}
}
}