Source: \core\renderers\canvas\CanvasRenderer.js
import SystemRenderer from '../SystemRenderer';
import CanvasMaskManager from './utils/CanvasMaskManager';
import CanvasRenderTarget from './utils/CanvasRenderTarget';
import mapCanvasBlendModesToPixi from './utils/mapCanvasBlendModesToPixi';
import { pluginTarget } from '../../utils';
import { RENDERER_TYPE, SCALE_MODES, BLEND_MODES } from '../../const';
import settings from '../../settings';
/**
* The CanvasRenderer draws the scene and all its content onto a 2d canvas. This renderer should
* be used for browsers that do not support WebGL. Don't forget to add the CanvasRenderer.view to
* your DOM or you will not see anything :)
*
* @class
* @memberof PIXI
* @extends PIXI.SystemRenderer
*/
export default class CanvasRenderer extends SystemRenderer
{
// eslint-disable-next-line valid-jsdoc
/**
* @param {object} [options] - The optional renderer parameters
* @param {number} [options.width=800] - the width of the screen
* @param {number} [options.height=600] - the height of the screen
* @param {HTMLCanvasElement} [options.view] - the canvas to use as a view, optional
* @param {boolean} [options.transparent=false] - If the render view is transparent, default false
* @param {boolean} [options.autoResize=false] - If the render view is automatically resized, default false
* @param {boolean} [options.antialias=false] - sets antialias (only applicable in chrome at the moment)
* @param {number} [options.resolution=1] - The resolution / device pixel ratio of the renderer. The
* resolution of the renderer retina would be 2.
* @param {boolean} [options.clearBeforeRender=true] - This sets if the CanvasRenderer will clear the canvas or
* not before the new render pass.
* @param {number} [options.backgroundColor=0x000000] - The background color of the rendered area
* (shown if not transparent).
* @param {boolean} [options.roundPixels=false] - If true Pixi will Math.floor() x/y values when rendering,
* stopping pixel interpolation.
*/
constructor(options, arg2, arg3)
{
super('Canvas', options, arg2, arg3);
this.type = RENDERER_TYPE.CANVAS;
/**
* The canvas 2d context that everything is drawn with.
*
* @member {CanvasRenderingContext2D}
*/
this.rootContext = this.view.getContext('2d', { alpha: this.transparent });
/**
* Boolean flag controlling canvas refresh.
*
* @member {boolean}
*/
this.refresh = true;
/**
* Instance of a CanvasMaskManager, handles masking when using the canvas renderer.
*
* @member {PIXI.CanvasMaskManager}
*/
this.maskManager = new CanvasMaskManager(this);
/**
* The canvas property used to set the canvas smoothing property.
*
* @member {string}
*/
this.smoothProperty = 'imageSmoothingEnabled';
if (!this.rootContext.imageSmoothingEnabled)
{
if (this.rootContext.webkitImageSmoothingEnabled)
{
this.smoothProperty = 'webkitImageSmoothingEnabled';
}
else if (this.rootContext.mozImageSmoothingEnabled)
{
this.smoothProperty = 'mozImageSmoothingEnabled';
}
else if (this.rootContext.oImageSmoothingEnabled)
{
this.smoothProperty = 'oImageSmoothingEnabled';
}
else if (this.rootContext.msImageSmoothingEnabled)
{
this.smoothProperty = 'msImageSmoothingEnabled';
}
}
this.initPlugins();
this.blendModes = mapCanvasBlendModesToPixi();
this._activeBlendMode = null;
this.context = null;
this.renderingToScreen = false;
this.resize(this.options.width, this.options.height);
}
/**
* Renders the object to this canvas view
*
* @param {PIXI.DisplayObject} displayObject - The object to be rendered
* @param {PIXI.RenderTexture} [renderTexture] - A render texture to be rendered to.
* If unset, it will render to the root context.
* @param {boolean} [clear=false] - Whether to clear the canvas before drawing
* @param {PIXI.Transform} [transform] - A transformation to be applied
* @param {boolean} [skipUpdateTransform=false] - Whether to skip the update transform
*/
render(displayObject, renderTexture, clear, transform, skipUpdateTransform)
{
if (!this.view)
{
return;
}
// can be handy to know!
this.renderingToScreen = !renderTexture;
this.emit('prerender');
const rootResolution = this.resolution;
if (renderTexture)
{
renderTexture = renderTexture.baseTexture || renderTexture;
if (!renderTexture._canvasRenderTarget)
{
renderTexture._canvasRenderTarget = new CanvasRenderTarget(
renderTexture.width,
renderTexture.height,
renderTexture.resolution
);
renderTexture.source = renderTexture._canvasRenderTarget.canvas;
renderTexture.valid = true;
}
this.context = renderTexture._canvasRenderTarget.context;
this.resolution = renderTexture._canvasRenderTarget.resolution;
}
else
{
this.context = this.rootContext;
}
const context = this.context;
if (!renderTexture)
{
this._lastObjectRendered = displayObject;
}
if (!skipUpdateTransform)
{
// update the scene graph
const cacheParent = displayObject.parent;
const tempWt = this._tempDisplayObjectParent.transform.worldTransform;
if (transform)
{
transform.copy(tempWt);
// lets not forget to flag the parent transform as dirty...
this._tempDisplayObjectParent.transform._worldID = -1;
}
else
{
tempWt.identity();
}
displayObject.parent = this._tempDisplayObjectParent;
displayObject.updateTransform();
displayObject.parent = cacheParent;
// displayObject.hitArea = //TODO add a temp hit area
}
context.setTransform(1, 0, 0, 1, 0, 0);
context.globalAlpha = 1;
context.globalCompositeOperation = this.blendModes[BLEND_MODES.NORMAL];
if (navigator.isCocoonJS && this.view.screencanvas)
{
context.fillStyle = 'black';
context.clear();
}
if (clear !== undefined ? clear : this.clearBeforeRender)
{
if (this.renderingToScreen)
{
if (this.transparent)
{
context.clearRect(0, 0, this.width, this.height);
}
else
{
context.fillStyle = this._backgroundColorString;
context.fillRect(0, 0, this.width, this.height);
}
} // else {
// TODO: implement background for CanvasRenderTarget or RenderTexture?
// }
}
// TODO RENDER TARGET STUFF HERE..
const tempContext = this.context;
this.context = context;
displayObject.renderCanvas(this);
this.context = tempContext;
this.resolution = rootResolution;
this.emit('postrender');
}
/**
* Clear the canvas of renderer.
*
* @param {string} [clearColor] - Clear the canvas with this color, except the canvas is transparent.
*/
clear(clearColor)
{
const context = this.context;
clearColor = clearColor || this._backgroundColorString;
if (!this.transparent && clearColor)
{
context.fillStyle = clearColor;
context.fillRect(0, 0, this.width, this.height);
}
else
{
context.clearRect(0, 0, this.width, this.height);
}
}
/**
* Sets the blend mode of the renderer.
*
* @param {number} blendMode - See {@link PIXI.BLEND_MODES} for valid values.
*/
setBlendMode(blendMode)
{
if (this._activeBlendMode === blendMode)
{
return;
}
this._activeBlendMode = blendMode;
this.context.globalCompositeOperation = this.blendModes[blendMode];
}
/**
* Removes everything from the renderer and optionally removes the Canvas DOM element.
*
* @param {boolean} [removeView=false] - Removes the Canvas element from the DOM.
*/
destroy(removeView)
{
this.destroyPlugins();
// call the base destroy
super.destroy(removeView);
this.context = null;
this.refresh = true;
this.maskManager.destroy();
this.maskManager = null;
this.smoothProperty = null;
}
/**
* Resizes the canvas view to the specified width and height.
*
* @extends PIXI.SystemRenderer#resize
*
* @param {number} screenWidth - the new width of the screen
* @param {number} screenHeight - the new height of the screen
*/
resize(screenWidth, screenHeight)
{
super.resize(screenWidth, screenHeight);
// reset the scale mode.. oddly this seems to be reset when the canvas is resized.
// surely a browser bug?? Let pixi fix that for you..
if (this.smoothProperty)
{
this.rootContext[this.smoothProperty] = (settings.SCALE_MODE === SCALE_MODES.LINEAR);
}
}
}
pluginTarget.mixin(CanvasRenderer);