Source: packages/core/src/textures/resources/ImageResource.js

packages/core/src/textures/resources/ImageResource.js

import { BaseImageResource } from './BaseImageResource';
import { settings } from '@pixi/settings';
import { ALPHA_MODES } from '@pixi/constants';
/**
 * Resource type for HTMLImageElement.
 * @class
 * @extends PIXI.resources.BaseImageResource
 * @memberof PIXI.resources
 */
export class ImageResource extends BaseImageResource {
    /**
     * @param {HTMLImageElement|string} source - image source or URL
     * @param {object} [options]
     * @param {boolean} [options.autoLoad=true] - start loading process
     * @param {boolean} [options.createBitmap=PIXI.settings.CREATE_IMAGE_BITMAP] - whether its required to create
     *        a bitmap before upload
     * @param {boolean} [options.crossorigin=true] - Load image using cross origin
     * @param {PIXI.ALPHA_MODES} [options.alphaMode=PIXI.ALPHA_MODES.UNPACK] - Premultiply image alpha in bitmap
     */
    constructor(source, options) {
        options = options || {};
        if (!(source instanceof HTMLImageElement)) {
            const imageElement = new Image();
            BaseImageResource.crossOrigin(imageElement, source, options.crossorigin);
            imageElement.src = source;
            source = imageElement;
        }
        super(source);
        // FireFox 68, and possibly other versions, seems like setting the HTMLImageElement#width and #height
        // to non-zero values before its loading completes if images are in a cache.
        // Because of this, need to set the `_width` and the `_height` to zero to avoid uploading incomplete images.
        // Please refer to the issue #5968 (https://github.com/pixijs/pixi.js/issues/5968).
        if (!source.complete && !!this._width && !!this._height) {
            this._width = 0;
            this._height = 0;
        }
        /**
         * URL of the image source
         * @member {string}
         */
        this.url = source.src;
        /**
         * When process is completed
         * @member {Promise<void>}
         * @private
         */
        this._process = null;
        /**
         * If the image should be disposed after upload
         * @member {boolean}
         * @default false
         */
        this.preserveBitmap = false;
        /**
         * If capable, convert the image using createImageBitmap API
         * @member {boolean}
         * @default PIXI.settings.CREATE_IMAGE_BITMAP
         */
        this.createBitmap = (options.createBitmap !== undefined
            ? options.createBitmap : settings.CREATE_IMAGE_BITMAP) && !!window.createImageBitmap;
        /**
         * Controls texture alphaMode field
         * Copies from options
         * Default is `null`, copies option from baseTexture
         *
         * @member {PIXI.ALPHA_MODES|null}
         * @readonly
         */
        this.alphaMode = typeof options.alphaMode === 'number' ? options.alphaMode : null;
        if (options.premultiplyAlpha !== undefined) {
            // triggers deprecation
            this.premultiplyAlpha = options.premultiplyAlpha;
        }
        /**
         * The ImageBitmap element created for HTMLImageElement
         * @member {ImageBitmap}
         * @default null
         */
        this.bitmap = null;
        /**
         * Promise when loading
         * @member {Promise<void>}
         * @private
         * @default null
         */
        this._load = null;
        if (options.autoLoad !== false) {
            this.load();
        }
    }
    /**
     * returns a promise when image will be loaded and processed
     *
     * @param {boolean} [createBitmap] - whether process image into bitmap
     * @returns {Promise<void>}
     */
    load(createBitmap) {
        if (this._load) {
            return this._load;
        }
        if (createBitmap !== undefined) {
            this.createBitmap = createBitmap;
        }
        this._load = new Promise((resolve, reject) => {
            const source = this.source;
            this.url = source.src;
            const completed = () => {
                if (this.destroyed) {
                    return;
                }
                source.onload = null;
                source.onerror = null;
                this.resize(source.width, source.height);
                this._load = null;
                if (this.createBitmap) {
                    resolve(this.process());
                }
                else {
                    resolve(this);
                }
            };
            if (source.complete && source.src) {
                completed();
            }
            else {
                source.onload = completed;
                source.onerror = (event) => {
                    // Avoids Promise freezing when resource broken
                    reject(event);
                    this.onError.emit(event);
                };
            }
        });
        return this._load;
    }
    /**
     * Called when we need to convert image into BitmapImage.
     * Can be called multiple times, real promise is cached inside.
     *
     * @returns {Promise<void>} cached promise to fill that bitmap
     */
    process() {
        const source = this.source;
        if (this._process !== null) {
            return this._process;
        }
        if (this.bitmap !== null || !window.createImageBitmap) {
            return Promise.resolve(this);
        }
        this._process = window.createImageBitmap(source, 0, 0, source.width, source.height, {
            premultiplyAlpha: this.alphaMode === ALPHA_MODES.UNPACK ? 'premultiply' : 'none',
        })
            .then((bitmap) => {
            if (this.destroyed) {
                return Promise.reject();
            }
            this.bitmap = bitmap;
            this.update();
            this._process = null;
            return Promise.resolve(this);
        });
        return this._process;
    }
    /**
     * Upload the image resource to GPU.
     *
     * @param {PIXI.Renderer} renderer - Renderer to upload to
     * @param {PIXI.BaseTexture} baseTexture - BaseTexture for this resource
     * @param {PIXI.GLTexture} glTexture - GLTexture to use
     * @returns {boolean} true is success
     */
    upload(renderer, baseTexture, glTexture) {
        if (typeof this.alphaMode === 'number') {
            // bitmap stores unpack premultiply flag, we dont have to notify texImage2D about it
            baseTexture.alphaMode = this.alphaMode;
        }
        if (!this.createBitmap) {
            return super.upload(renderer, baseTexture, glTexture);
        }
        if (!this.bitmap) {
            // yeah, ignore the output
            this.process();
            if (!this.bitmap) {
                return false;
            }
        }
        super.upload(renderer, baseTexture, glTexture, this.bitmap);
        if (!this.preserveBitmap) {
            // checks if there are other renderers that possibly need this bitmap
            let flag = true;
            const glTextures = baseTexture._glTextures;
            for (const key in glTextures) {
                const otherTex = glTextures[key];
                if (otherTex !== glTexture && otherTex.dirtyId !== baseTexture.dirtyId) {
                    flag = false;
                    break;
                }
            }
            if (flag) {
                if (this.bitmap.close) {
                    this.bitmap.close();
                }
                this.bitmap = null;
            }
        }
        return true;
    }
    /**
     * Destroys this texture
     * @override
     */
    dispose() {
        this.source.onload = null;
        this.source.onerror = null;
        super.dispose();
        if (this.bitmap) {
            this.bitmap.close();
            this.bitmap = null;
        }
        this._process = null;
        this._load = null;
    }
    /**
     * Used to auto-detect the type of resource.
     *
     * @static
     * @param {string|HTMLImageElement} source - The source object
     * @return {boolean} `true` if source is string or HTMLImageElement
     */
    static test(source) {
        return typeof source === 'string' || source instanceof HTMLImageElement;
    }
}