Source: \core\textures\BaseTexture.js
import {
uid, getUrlFileExtension, decomposeDataUri, getSvgSize,
getResolutionOfUrl, BaseTextureCache, TextureCache,
} from '../utils';
import settings from '../settings';
import EventEmitter from 'eventemitter3';
import determineCrossOrigin from '../utils/determineCrossOrigin';
import bitTwiddle from 'bit-twiddle';
/**
* A texture stores the information that represents an image. All textures have a base texture.
*
* @class
* @extends EventEmitter
* @memberof PIXI
*/
export default class BaseTexture extends EventEmitter
{
/**
* @param {HTMLImageElement|HTMLCanvasElement} [source] - the source object of the texture.
* @param {number} [scaleMode=PIXI.settings.SCALE_MODE] - See {@link PIXI.SCALE_MODES} for possible values
* @param {number} [resolution=1] - The resolution / device pixel ratio of the texture
*/
constructor(source, scaleMode, resolution)
{
super();
this.uid = uid();
this.touched = 0;
/**
* The resolution / device pixel ratio of the texture
*
* @member {number}
* @default 1
*/
this.resolution = resolution || settings.RESOLUTION;
/**
* The width of the base texture set when the image has loaded
*
* @readonly
* @member {number}
*/
this.width = 100;
/**
* The height of the base texture set when the image has loaded
*
* @readonly
* @member {number}
*/
this.height = 100;
// TODO docs
// used to store the actual dimensions of the source
/**
* Used to store the actual width of the source of this texture
*
* @readonly
* @member {number}
*/
this.realWidth = 100;
/**
* Used to store the actual height of the source of this texture
*
* @readonly
* @member {number}
*/
this.realHeight = 100;
/**
* The scale mode to apply when scaling this texture
*
* @member {number}
* @default PIXI.settings.SCALE_MODE
* @see PIXI.SCALE_MODES
*/
this.scaleMode = scaleMode !== undefined ? scaleMode : settings.SCALE_MODE;
/**
* Set to true once the base texture has successfully loaded.
*
* This is never true if the underlying source fails to load or has no texture data.
*
* @readonly
* @member {boolean}
*/
this.hasLoaded = false;
/**
* Set to true if the source is currently loading.
*
* If an Image source is loading the 'loaded' or 'error' event will be
* dispatched when the operation ends. An underyling source that is
* immediately-available bypasses loading entirely.
*
* @readonly
* @member {boolean}
*/
this.isLoading = false;
/**
* The image source that is used to create the texture.
*
* TODO: Make this a setter that calls loadSource();
*
* @readonly
* @member {HTMLImageElement|HTMLCanvasElement}
*/
this.source = null; // set in loadSource, if at all
/**
* The image source that is used to create the texture. This is used to
* store the original Svg source when it is replaced with a canvas element.
*
* TODO: Currently not in use but could be used when re-scaling svg.
*
* @readonly
* @member {Image}
*/
this.origSource = null; // set in loadSvg, if at all
/**
* Type of image defined in source, eg. `png` or `svg`
*
* @readonly
* @member {string}
*/
this.imageType = null; // set in updateImageType
/**
* Scale for source image. Used with Svg images to scale them before rasterization.
*
* @readonly
* @member {number}
*/
this.sourceScale = 1.0;
/**
* Controls if RGB channels should be pre-multiplied by Alpha (WebGL only)
* All blend modes, and shaders written for default value. Change it on your own risk.
*
* @member {boolean}
* @default true
*/
this.premultipliedAlpha = true;
/**
* The image url of the texture
*
* @member {string}
*/
this.imageUrl = null;
/**
* Whether or not the texture is a power of two, try to use power of two textures as much
* as you can
*
* @private
* @member {boolean}
*/
this.isPowerOfTwo = false;
// used for webGL
/**
*
* Set this to true if a mipmap of this texture needs to be generated. This value needs
* to be set before the texture is used
* Also the texture must be a power of two size to work
*
* @member {boolean}
* @see PIXI.MIPMAP_TEXTURES
*/
this.mipmap = settings.MIPMAP_TEXTURES;
/**
*
* WebGL Texture wrap mode
*
* @member {number}
* @see PIXI.WRAP_MODES
*/
this.wrapMode = settings.WRAP_MODE;
/**
* A map of renderer IDs to webgl textures
*
* @private
* @member {object}
*/
this._glTextures = {};
this._enabled = 0;
this._virtalBoundId = -1;
// if no source passed don't try to load
if (source)
{
this.loadSource(source);
}
/**
* If the object has been destroyed via destroy(). If true, it should not be used.
*
* @member {boolean}
* @private
* @readonly
*/
this._destroyed = false;
/**
* Fired when a not-immediately-available source finishes loading.
*
* @protected
* @event loaded
* @memberof PIXI.BaseTexture#
*/
/**
* Fired when a not-immediately-available source fails to load.
*
* @protected
* @event error
* @memberof PIXI.BaseTexture#
*/
}
/**
* Updates the texture on all the webgl renderers, this also assumes the src has changed.
*
* @fires update
*/
update()
{
// Svg size is handled during load
if (this.imageType !== 'svg')
{
this.realWidth = this.source.naturalWidth || this.source.videoWidth || this.source.width;
this.realHeight = this.source.naturalHeight || this.source.videoHeight || this.source.height;
this._updateDimensions();
}
this.emit('update', this);
}
/**
* Update dimensions from real values
*/
_updateDimensions()
{
this.width = this.realWidth / this.resolution;
this.height = this.realHeight / this.resolution;
this.isPowerOfTwo = bitTwiddle.isPow2(this.realWidth) && bitTwiddle.isPow2(this.realHeight);
}
/**
* Load a source.
*
* If the source is not-immediately-available, such as an image that needs to be
* downloaded, then the 'loaded' or 'error' event will be dispatched in the future
* and `hasLoaded` will remain false after this call.
*
* The logic state after calling `loadSource` directly or indirectly (eg. `fromImage`, `new BaseTexture`) is:
*
* if (texture.hasLoaded) {
* // texture ready for use
* } else if (texture.isLoading) {
* // listen to 'loaded' and/or 'error' events on texture
* } else {
* // not loading, not going to load UNLESS the source is reloaded
* // (it may still make sense to listen to the events)
* }
*
* @protected
* @param {HTMLImageElement|HTMLCanvasElement} source - the source object of the texture.
*/
loadSource(source)
{
const wasLoading = this.isLoading;
this.hasLoaded = false;
this.isLoading = false;
if (wasLoading && this.source)
{
this.source.onload = null;
this.source.onerror = null;
}
const firstSourceLoaded = !this.source;
this.source = source;
// Apply source if loaded. Otherwise setup appropriate loading monitors.
if (((source.src && source.complete) || source.getContext) && source.width && source.height)
{
this._updateImageType();
if (this.imageType === 'svg')
{
this._loadSvgSource();
}
else
{
this._sourceLoaded();
}
if (firstSourceLoaded)
{
// send loaded event if previous source was null and we have been passed a pre-loaded IMG element
this.emit('loaded', this);
}
}
else if (!source.getContext)
{
// Image fail / not ready
this.isLoading = true;
const scope = this;
source.onload = () =>
{
scope._updateImageType();
source.onload = null;
source.onerror = null;
if (!scope.isLoading)
{
return;
}
scope.isLoading = false;
scope._sourceLoaded();
if (scope.imageType === 'svg')
{
scope._loadSvgSource();
return;
}
scope.emit('loaded', scope);
};
source.onerror = () =>
{
source.onload = null;
source.onerror = null;
if (!scope.isLoading)
{
return;
}
scope.isLoading = false;
scope.emit('error', scope);
};
// Per http://www.w3.org/TR/html5/embedded-content-0.html#the-img-element
// "The value of `complete` can thus change while a script is executing."
// So complete needs to be re-checked after the callbacks have been added..
// NOTE: complete will be true if the image has no src so best to check if the src is set.
if (source.complete && source.src)
{
// ..and if we're complete now, no need for callbacks
source.onload = null;
source.onerror = null;
if (scope.imageType === 'svg')
{
scope._loadSvgSource();
return;
}
this.isLoading = false;
if (source.width && source.height)
{
this._sourceLoaded();
// If any previous subscribers possible
if (wasLoading)
{
this.emit('loaded', this);
}
}
// If any previous subscribers possible
else if (wasLoading)
{
this.emit('error', this);
}
}
}
}
/**
* Updates type of the source image.
*/
_updateImageType()
{
if (!this.imageUrl)
{
return;
}
const dataUri = decomposeDataUri(this.imageUrl);
let imageType;
if (dataUri && dataUri.mediaType === 'image')
{
// Check for subType validity
const firstSubType = dataUri.subType.split('+')[0];
imageType = getUrlFileExtension(`.${firstSubType}`);
if (!imageType)
{
throw new Error('Invalid image type in data URI.');
}
}
else
{
imageType = getUrlFileExtension(this.imageUrl);
if (!imageType)
{
imageType = 'png';
}
}
this.imageType = imageType;
}
/**
* Checks if `source` is an SVG image and whether it's loaded via a URL or a data URI. Then calls
* `_loadSvgSourceUsingDataUri` or `_loadSvgSourceUsingXhr`.
*/
_loadSvgSource()
{
if (this.imageType !== 'svg')
{
// Do nothing if source is not svg
return;
}
const dataUri = decomposeDataUri(this.imageUrl);
if (dataUri)
{
this._loadSvgSourceUsingDataUri(dataUri);
}
else
{
// We got an URL, so we need to do an XHR to check the svg size
this._loadSvgSourceUsingXhr();
}
}
/**
* Reads an SVG string from data URI and then calls `_loadSvgSourceUsingString`.
*
* @param {string} dataUri - The data uri to load from.
*/
_loadSvgSourceUsingDataUri(dataUri)
{
let svgString;
if (dataUri.encoding === 'base64')
{
if (!atob)
{
throw new Error('Your browser doesn\'t support base64 conversions.');
}
svgString = atob(dataUri.data);
}
else
{
svgString = dataUri.data;
}
this._loadSvgSourceUsingString(svgString);
}
/**
* Loads an SVG string from `imageUrl` using XHR and then calls `_loadSvgSourceUsingString`.
*/
_loadSvgSourceUsingXhr()
{
const svgXhr = new XMLHttpRequest();
// This throws error on IE, so SVG Document can't be used
// svgXhr.responseType = 'document';
// This is not needed since we load the svg as string (breaks IE too)
// but overrideMimeType() can be used to force the response to be parsed as XML
// svgXhr.overrideMimeType('image/svg+xml');
svgXhr.onload = () =>
{
if (svgXhr.readyState !== svgXhr.DONE || svgXhr.status !== 200)
{
throw new Error('Failed to load SVG using XHR.');
}
this._loadSvgSourceUsingString(svgXhr.response);
};
svgXhr.onerror = () => this.emit('error', this);
svgXhr.open('GET', this.imageUrl, true);
svgXhr.send();
}
/**
* Loads texture using an SVG string. The original SVG Image is stored as `origSource` and the
* created canvas is the new `source`. The SVG is scaled using `sourceScale`. Called by
* `_loadSvgSourceUsingXhr` or `_loadSvgSourceUsingDataUri`.
*
* @param {string} svgString SVG source as string
*
* @fires loaded
*/
_loadSvgSourceUsingString(svgString)
{
const svgSize = getSvgSize(svgString);
const svgWidth = svgSize.width;
const svgHeight = svgSize.height;
if (!svgWidth || !svgHeight)
{
throw new Error('The SVG image must have width and height defined (in pixels), canvas API needs them.');
}
// Scale realWidth and realHeight
this.realWidth = Math.round(svgWidth * this.sourceScale);
this.realHeight = Math.round(svgHeight * this.sourceScale);
this._updateDimensions();
// Create a canvas element
const canvas = document.createElement('canvas');
canvas.width = this.realWidth;
canvas.height = this.realHeight;
canvas._pixiId = `canvas_${uid()}`;
// Draw the Svg to the canvas
canvas
.getContext('2d')
.drawImage(this.source, 0, 0, svgWidth, svgHeight, 0, 0, this.realWidth, this.realHeight);
// Replace the original source image with the canvas
this.origSource = this.source;
this.source = canvas;
// Add also the canvas in cache (destroy clears by `imageUrl` and `source._pixiId`)
BaseTextureCache[canvas._pixiId] = this;
this.isLoading = false;
this._sourceLoaded();
this.emit('loaded', this);
}
/**
* Used internally to update the width, height, and some other tracking vars once
* a source has successfully loaded.
*
* @private
*/
_sourceLoaded()
{
this.hasLoaded = true;
this.update();
}
/**
* Destroys this base texture
*
*/
destroy()
{
if (this.imageUrl)
{
delete TextureCache[this.imageUrl];
this.imageUrl = null;
if (!navigator.isCocoonJS)
{
this.source.src = '';
}
}
this.source = null;
this.dispose();
for (const prop in BaseTextureCache)
{
if (BaseTextureCache[prop] === this)
{
delete BaseTextureCache[prop];
}
}
this._destroyed = true;
}
/**
* Frees the texture from WebGL memory without destroying this texture object.
* This means you can still use the texture later which will upload it to GPU
* memory again.
*
*/
dispose()
{
this.emit('dispose', this);
}
/**
* Changes the source image of the texture.
* The original source must be an Image element.
*
* @param {string} newSrc - the path of the image
*/
updateSourceImage(newSrc)
{
this.source.src = newSrc;
this.loadSource(this.source);
}
/**
* Helper function that creates a base texture from the given image url.
* If the image is not in the base texture cache it will be created and loaded.
*
* @static
* @param {string} imageUrl - The image url of the texture
* @param {boolean} [crossorigin=(auto)] - Should use anonymous CORS? Defaults to true if the URL is not a data-URI.
* @param {number} [scaleMode=PIXI.settings.SCALE_MODE] - See {@link PIXI.SCALE_MODES} for possible values
* @param {number} [sourceScale=(auto)] - Scale for the original image, used with Svg images.
* @return {PIXI.BaseTexture} The new base texture.
*/
static fromImage(imageUrl, crossorigin, scaleMode, sourceScale)
{
let baseTexture = BaseTextureCache[imageUrl];
if (!baseTexture)
{
// new Image() breaks tex loading in some versions of Chrome.
// See https://code.google.com/p/chromium/issues/detail?id=238071
const image = new Image();// document.createElement('img');
if (crossorigin === undefined && imageUrl.indexOf('data:') !== 0)
{
image.crossOrigin = determineCrossOrigin(imageUrl);
}
baseTexture = new BaseTexture(image, scaleMode);
baseTexture.imageUrl = imageUrl;
if (sourceScale)
{
baseTexture.sourceScale = sourceScale;
}
// if there is an @2x at the end of the url we are going to assume its a highres image
baseTexture.resolution = getResolutionOfUrl(imageUrl);
image.src = imageUrl; // Setting this triggers load
BaseTextureCache[imageUrl] = baseTexture;
}
return baseTexture;
}
/**
* Helper function that creates a base texture from the given canvas element.
*
* @static
* @param {HTMLCanvasElement} canvas - The canvas element source of the texture
* @param {number} scaleMode - See {@link PIXI.SCALE_MODES} for possible values
* @return {PIXI.BaseTexture} The new base texture.
*/
static fromCanvas(canvas, scaleMode)
{
if (!canvas._pixiId)
{
canvas._pixiId = `canvas_${uid()}`;
}
let baseTexture = BaseTextureCache[canvas._pixiId];
if (!baseTexture)
{
baseTexture = new BaseTexture(canvas, scaleMode);
BaseTextureCache[canvas._pixiId] = baseTexture;
}
return baseTexture;
}
/**
* Helper function that creates a base texture based on the source you provide.
* The source can be - image url, image element, canvas element.
*
* @static
* @param {string|HTMLImageElement|HTMLCanvasElement} source - The source to create base texture from.
* @param {number} [scaleMode=PIXI.settings.SCALE_MODE] - See {@link PIXI.SCALE_MODES} for possible values
* @param {number} [sourceScale=(auto)] - Scale for the original image, used with Svg images.
* @return {PIXI.BaseTexture} The new base texture.
*/
static from(source, scaleMode, sourceScale)
{
if (typeof source === 'string')
{
return BaseTexture.fromImage(source, undefined, scaleMode, sourceScale);
}
else if (source instanceof HTMLImageElement)
{
const imageUrl = source.src;
let baseTexture = BaseTextureCache[imageUrl];
if (!baseTexture)
{
baseTexture = new BaseTexture(source, scaleMode);
baseTexture.imageUrl = imageUrl;
if (sourceScale)
{
baseTexture.sourceScale = sourceScale;
}
// if there is an @2x at the end of the url we are going to assume its a highres image
baseTexture.resolution = getResolutionOfUrl(imageUrl);
BaseTextureCache[imageUrl] = baseTexture;
}
return baseTexture;
}
else if (source instanceof HTMLCanvasElement)
{
return BaseTexture.fromCanvas(source, scaleMode);
}
// lets assume its a base texture!
return source;
}
}