import { BaseTexture, BLEND_MODES, Color, extensions, ExtensionType, Matrix, SCALE_MODES } from '@pixi/core';
import { mapCanvasBlendModesToPixi } from './utils/mapCanvasBlendModesToPixi';
import type { ColorSource, ExtensionMetadata, ICanvasRenderingContext2D, ISystem } from '@pixi/core';
import type { CanvasRenderer } from './CanvasRenderer';
const tempMatrix = new Matrix();
/**
* Rendering context for all browsers. This includes platform-specific
* properties that are not included in the spec for CanvasRenderingContext2D
*/
export interface CrossPlatformCanvasRenderingContext2D extends ICanvasRenderingContext2D
{
webkitImageSmoothingEnabled: boolean;
mozImageSmoothingEnabled: boolean;
oImageSmoothingEnabled: boolean;
msImageSmoothingEnabled: boolean;
}
/*
* Different browsers support different smoothing property names
* this is the list of all platform props.
*/
export type SmoothingEnabledProperties =
'imageSmoothingEnabled' |
'webkitImageSmoothingEnabled' |
'mozImageSmoothingEnabled' |
'oImageSmoothingEnabled' |
'msImageSmoothingEnabled';
/**
* System that manages the canvas `2d` contexts
* @memberof PIXI
*/
export class CanvasContextSystem implements ISystem
{
/** @ignore */
static extension: ExtensionMetadata = {
type: ExtensionType.CanvasRendererSystem,
name: 'canvasContext',
};
/** A reference to the current renderer */
private renderer: CanvasRenderer;
/** The root canvas 2d context that everything is drawn with. */
public rootContext: CrossPlatformCanvasRenderingContext2D;
/** The currently active canvas 2d context (could change with renderTextures) */
public activeContext: CrossPlatformCanvasRenderingContext2D;
public activeResolution = 1;
/** The canvas property used to set the canvas smoothing property. */
public smoothProperty: SmoothingEnabledProperties = 'imageSmoothingEnabled';
/** Tracks the blend modes useful for this renderer. */
public readonly blendModes: string[] = mapCanvasBlendModesToPixi();
_activeBlendMode: BLEND_MODES = null;
/** Projection transform, passed in render() stored here */
_projTransform: Matrix = null;
/** @private */
_outerBlend = false;
/** @param renderer - A reference to the current renderer */
constructor(renderer: CanvasRenderer)
{
this.renderer = renderer;
}
/** initiates the system */
init(): void
{
const alpha = this.renderer.background.alpha < 1;
this.rootContext = this.renderer.view.getContext('2d', { alpha }) as
CrossPlatformCanvasRenderingContext2D;
this.activeContext = this.rootContext;
if (!this.rootContext.imageSmoothingEnabled)
{
const rc = this.rootContext;
if (rc.webkitImageSmoothingEnabled)
{
this.smoothProperty = 'webkitImageSmoothingEnabled';
}
else if (rc.mozImageSmoothingEnabled)
{
this.smoothProperty = 'mozImageSmoothingEnabled';
}
else if (rc.oImageSmoothingEnabled)
{
this.smoothProperty = 'oImageSmoothingEnabled';
}
else if (rc.msImageSmoothingEnabled)
{
this.smoothProperty = 'msImageSmoothingEnabled';
}
}
}
/**
* Sets matrix of context.
* called only from render() methods
* takes care about resolution
* @param transform - world matrix of current element
* @param roundPixels - whether to round (tx,ty) coords
* @param localResolution - If specified, used instead of `renderer.resolution` for local scaling
*/
setContextTransform(transform: Matrix, roundPixels?: boolean, localResolution?: number): void
{
let mat = transform;
const proj = this._projTransform;
const contextResolution = this.activeResolution;
localResolution = localResolution || contextResolution;
if (proj)
{
mat = tempMatrix;
mat.copyFrom(transform);
mat.prepend(proj);
}
if (roundPixels)
{
this.activeContext.setTransform(
mat.a * localResolution,
mat.b * localResolution,
mat.c * localResolution,
mat.d * localResolution,
(mat.tx * contextResolution) | 0,
(mat.ty * contextResolution) | 0
);
}
else
{
this.activeContext.setTransform(
mat.a * localResolution,
mat.b * localResolution,
mat.c * localResolution,
mat.d * localResolution,
mat.tx * contextResolution,
mat.ty * contextResolution
);
}
}
/**
* Clear the canvas of renderer.
* @param {string} [clearColor] - Clear the canvas with this color, except the canvas is transparent.
* @param {number} [alpha] - Alpha to apply to the background fill color.
*/
public clear(clearColor?: ColorSource, alpha?: number): void
{
const { activeContext: context, renderer } = this;
const fillColor = clearColor
? Color.shared.setValue(clearColor)
: this.renderer.background.backgroundColor;
context.clearRect(0, 0, renderer.width, renderer.height);
if (clearColor)
{
context.globalAlpha = alpha ?? this.renderer.background.alpha;
context.fillStyle = fillColor.toHex();
context.fillRect(0, 0, renderer.width, renderer.height);
context.globalAlpha = 1;
}
}
/**
* Sets the blend mode of the renderer.
* @param {number} blendMode - See PIXI.BLEND_MODES for valid values.
* @param {boolean} [readyForOuterBlend=false] - Some blendModes are dangerous, they affect outer space of sprite.
* Pass `true` only if you are ready to use them.
*/
setBlendMode(blendMode: BLEND_MODES, readyForOuterBlend?: boolean): void
{
const outerBlend = blendMode === BLEND_MODES.SRC_IN
|| blendMode === BLEND_MODES.SRC_OUT
|| blendMode === BLEND_MODES.DST_IN
|| blendMode === BLEND_MODES.DST_ATOP;
if (!readyForOuterBlend && outerBlend)
{
blendMode = BLEND_MODES.NORMAL;
}
if (this._activeBlendMode === blendMode)
{
return;
}
this._activeBlendMode = blendMode;
this._outerBlend = outerBlend;
this.activeContext.globalCompositeOperation = this.blendModes[blendMode];
}
resize(): void
{
// reset the scale mode.. oddly this seems to be reset when the canvas is resized.
// surely a browser bug?? Let PixiJS fix that for you..
if (this.smoothProperty)
{
this.rootContext[this.smoothProperty] = (BaseTexture.defaultOptions.scaleMode === SCALE_MODES.LINEAR);
}
}
/** Checks if blend mode has changed. */
invalidateBlendMode(): void
{
this._activeBlendMode = this.blendModes.indexOf(this.activeContext.globalCompositeOperation);
}
public destroy(): void
{
this.renderer = null;
this.rootContext = null;
this.activeContext = null;
this.smoothProperty = null;
}
}
extensions.add(CanvasContextSystem);