Source: tiny/core/textures/Texture.js

import BaseTexture from './BaseTexture';
import VideoBaseTexture from './VideoBaseTexture';
import TextureUvs from './TextureUvs';
import EventEmitter from 'eventemitter3';
import { Rectangle, Point } from '../math';
import { TextureCache } from '../utils';
import { getResolutionOfUrl } from '../../../utils';
import settings from '../settings';

/**
 * A texture stores the information that represents an image or part of an image. It cannot be added to the display list directly. Instead use it as the texture for a Sprite. If no frame is provided then the whole image is used.
 *
 * You can directly create a texture from an image and then reuse it multiple times like this :
 *
 * ```js
 * let texture = Tiny.Texture.fromImage('assets/image.png');
 * let sprite1 = new Tiny.Sprite(texture);
 * let sprite2 = new Tiny.Sprite(texture);
 * ```
 *
 * Textures made from SVGs, loaded or not, cannot be used before the file finishes processing.
 * You can check for this by checking the sprite's _textureID property.
 * ```js
 * var texture = Tiny.Texture.fromImage('assets/image.svg');
 * var sprite1 = new Tiny.Sprite(texture);
 * //sprite1._textureID should not be undefined if the texture has finished processing the SVG file
 * ```
 * You can use a ticker or rAF to ensure your sprites load the finished textures after processing. See issue #3068.
 *
 * @class
 * @extends EventEmitter
 * @memberof Tiny
 */
export default class Texture extends EventEmitter {
  /**
   * @param {Tiny.BaseTexture} baseTexture - The base texture source to create the texture from
   * @param {Tiny.Rectangle} [frame] - The rectangle frame of the texture to show
   * @param {Tiny.Rectangle} [orig] - The area of original texture
   * @param {Tiny.Rectangle} [trim] - Trimmed rectangle of original texture
   * @param {number} [rotate] - indicates how the texture was rotated by texture packer. See {@link Tiny.GroupD8}
   * @param {Tiny.Point} [anchor] - Default anchor point used for sprite placement / rotation
   */
  constructor(baseTexture, frame, orig, trim, rotate, anchor) {
    super();

    /**
     * Does this Texture have any frame data assigned to it?
     *
     * @member {boolean}
     */
    this.noFrame = false;

    if (!frame) {
      this.noFrame = true;
      frame = new Rectangle(0, 0, 1, 1);
    }

    if (baseTexture instanceof Texture) {
      baseTexture = baseTexture.baseTexture;
    }

    /**
     * The base texture that this texture uses.
     *
     * @member {Tiny.BaseTexture}
     */
    this.baseTexture = baseTexture;

    /**
     * This is the area of the BaseTexture image to actually copy to the Canvas / WebGL when rendering, irrespective of the actual frame size or placement (which can be influenced by trimmed texture atlases)
     *
     * @member {Tiny.Rectangle}
     */
    this._frame = frame;

    /**
     * This is the trimmed area of original texture, before it was put in atlas
     * Please call `_updateUvs()` after you change coordinates of `trim` manually.
     *
     * @member {Tiny.Rectangle}
     */
    this.trim = trim;

    /**
     * This will let the renderer know if the texture is valid. If it's not then it cannot be rendered.
     *
     * @member {boolean}
     */
    this.valid = false;

    /**
     * This will let a renderer know that a texture has been updated (used mainly for webGL uv updates)
     *
     * @member {boolean}
     */
    this.requiresUpdate = false;

    /**
     * The WebGL UV data cache.
     *
     * @member {Tiny.TextureUvs}
     * @private
     */
    this._uvs = null;

    /**
     * This is the area of original texture, before it was put in atlas
     *
     * @member {Tiny.Rectangle}
     */
    this.orig = orig || frame; // new Rectangle(0, 0, 1, 1);

    this._rotate = Number(rotate || 0);

    if (rotate === true) {
      // this is old texturepacker legacy, some games/libraries are passing "true" for rotated textures
      this._rotate = 2;
    } else if (this._rotate % 2 !== 0) {
      throw new Error('attempt to use diamond-shaped UVs. If you are sure, set rotation manually');
    }

    if (baseTexture.hasLoaded) {
      if (this.noFrame) {
        frame = new Rectangle(0, 0, baseTexture.width, baseTexture.height);

        // if there is no frame we should monitor for any base texture changes..
        baseTexture.on('update', this.onBaseTextureUpdated, this);
      }
      this.frame = frame;
    } else {
      baseTexture.once('loaded', this.onBaseTextureLoaded, this);
    }

    /**
     * Anchor point that is used as default if sprite is created with this texture.
     * Changing the `defaultAnchor` at a later point of time will not update Sprite's anchor point.
     *
     * @version 1.2.0
     * @member {Tiny.Point}
     * @default {0,0}
     */
    this.defaultAnchor = anchor ? new Point(anchor.x, anchor.y) : new Point(0, 0);

    /**
     * Fired when the texture is updated. This happens if the frame or the baseTexture is updated.
     *
     * @event update
     * @memberof Tiny.Texture#
     * @protected
     */

    this._updateID = 0;

    /**
     * Contains data for uvs. May contain clamp settings and some matrices.
     * Its a bit heavy, so by default that object is not created.
     *
     * @member {Tiny.TextureTransform}
     * @default null
     */
    this.transform = null;

    /**
     * The ids under which this Texture has been added to the texture cache. This is automatically set as long as Texture.addToCache is used, but may not be set if a
     * Texture is added directly to the TextureCache array.
     *
     * @member {string[]}
     */
    this.textureCacheIds = [];
  }

  /**
   * Updates this texture on the gpu.
   *
   */
  update() {
    this.baseTexture.update();
  }

  /**
   * Called when the base texture is loaded
   *
   * @private
   * @param {Tiny.BaseTexture} baseTexture - The base texture.
   */
  onBaseTextureLoaded(baseTexture) {
    this._updateID++;

    // TODO this code looks confusing.. boo to abusing getters and setters!
    if (this.noFrame) {
      this.frame = new Rectangle(0, 0, baseTexture.width, baseTexture.height);
    } else {
      this.frame = this._frame;
    }

    this.baseTexture.on('update', this.onBaseTextureUpdated, this);
    this.emit('update', this);
  }

  /**
   * Called when the base texture is updated
   *
   * @private
   * @param {Tiny.BaseTexture} baseTexture - The base texture.
   */
  onBaseTextureUpdated(baseTexture) {
    this._updateID++;

    this._frame.width = baseTexture.width;
    this._frame.height = baseTexture.height;

    this.emit('update', this);
  }

  /**
   * Destroys this texture
   *
   * @param {boolean} [destroyBase=false] - Whether to destroy the base texture as well
   */
  destroy(destroyBase) {
    if (this.baseTexture) {
      if (destroyBase) {
        // delete the texture if it exists in the texture cache..
        // this only needs to be removed if the base texture is actually destroyed too..
        if (TextureCache[this.baseTexture.imageUrl]) {
          Texture.removeFromCache(this.baseTexture.imageUrl);
        }

        this.baseTexture.destroy();
      }

      this.baseTexture.off('update', this.onBaseTextureUpdated, this);
      this.baseTexture.off('loaded', this.onBaseTextureLoaded, this);

      this.baseTexture = null;
    }

    this._frame = null;
    this._uvs = null;
    this.trim = null;
    this.orig = null;

    this.valid = false;

    Texture.removeFromCache(this);
    this.textureCacheIds = null;
  }

  /**
   * Creates a new texture object that acts the same as this one.
   *
   * @return {Tiny.Texture} The new texture
   */
  clone() {
    return new Texture(this.baseTexture, this.frame, this.orig, this.trim, this.rotate, this.defaultAnchor);
  }

  /**
   * Updates the internal WebGL UV cache. Use it after you change `frame` or `trim` of the texture.
   */
  _updateUvs() {
    if (!this._uvs) {
      this._uvs = new TextureUvs();
    }

    this._uvs.set(this._frame, this.baseTexture, this.rotate);

    this._updateID++;
  }

  /**
   * Helper function that creates a Texture object from the given image url.
   * If the image is not in the texture cache it will be  created and loaded.
   *
   * @static
   * @param {string} imageUrl - The image url of the texture
   * @param {boolean} [crossorigin] - Whether requests should be treated as crossorigin
   * @param {number} [scaleMode=Tiny.settings.SCALE_MODE] - See {@link Tiny.SCALE_MODES} for possible values
   * @param {number} [sourceScale=(auto)] - Scale for the original image, used with SVG images.
   * @return {Tiny.Texture} The newly created texture
   */
  static fromImage(imageUrl, crossorigin, scaleMode, sourceScale) {
    let texture = TextureCache[imageUrl];

    if (!texture) {
      texture = new Texture(BaseTexture.fromImage(imageUrl, crossorigin, scaleMode, sourceScale));
      Texture.addToCache(texture, imageUrl);
    }

    return texture;
  }

  /**
   * Helper function that creates a sprite that will contain a texture from the TextureCache based on the frameId
   * The frame ids are created when a Texture packer file has been loaded
   *
   * @static
   * @param {string} frameId - The frame Id of the texture in the cache
   * @return {Tiny.Texture} The newly created texture
   */
  static fromFrame(frameId) {
    const texture = TextureCache[frameId];

    if (!texture) {
      throw new Error(`The frameId "${frameId}" does not exist in the texture cache`);
    }

    return texture;
  }

  /**
   * Helper function that creates a new Texture based on the given canvas element.
   *
   * @static
   * @param {HTMLCanvasElement} canvas - The canvas element source of the texture
   * @param {number} [scaleMode=Tiny.settings.SCALE_MODE] - See {@link Tiny.SCALE_MODES} for possible values
   * @param {string} [origin='canvas'] - A string origin of who created the base texture
   * @return {Tiny.Texture} The newly created texture
   */
  static fromCanvas(canvas, scaleMode, origin = 'canvas') {
    return new Texture(BaseTexture.fromCanvas(canvas, scaleMode, origin));
  }

  /**
   * Helper function that creates a new Texture based on the given video element.
   *
   * @static
   * @param {HTMLVideoElement|string} video - The URL or actual element of the video
   * @param {number} [scaleMode=Tiny.settings.SCALE_MODE] - See {@link Tiny.SCALE_MODES} for possible values
   * @param {boolean} [crossorigin=(auto)] - Should use anonymous CORS? Defaults to true if the URL is not a data-URI.
   * @param {boolean} [autoPlay=true] - Start playing video as soon as it is loaded
   * @return {Tiny.Texture} The newly created texture
   */
  static fromVideo(video, scaleMode, crossorigin, autoPlay) {
    if (typeof video === 'string') {
      return Texture.fromVideoUrl(video, scaleMode, crossorigin, autoPlay);
    }

    return new Texture(VideoBaseTexture.fromVideo(video, scaleMode, autoPlay));
  }

  /**
   * Helper function that creates a new Texture based on the video url.
   *
   * @static
   * @param {string} videoUrl - URL of the video
   * @param {number} [scaleMode=Tiny.settings.SCALE_MODE] - See {@link Tiny.SCALE_MODES} for possible values
   * @param {boolean} [crossorigin=(auto)] - Should use anonymous CORS? Defaults to true if the URL is not a data-URI.
   * @param {boolean} [autoPlay=true] - Start playing video as soon as it is loaded
   * @return {Tiny.Texture} The newly created texture
   */
  static fromVideoUrl(videoUrl, scaleMode, crossorigin, autoPlay) {
    return new Texture(VideoBaseTexture.fromUrl(videoUrl, scaleMode, crossorigin, autoPlay));
  }

  /**
   * Helper function that creates a new Texture based on the source you provide.
   * The source can be - frame id, image url, video url, canvas element, video element, base texture
   *
   * @static
   * @param {number|string|Tiny.BaseTexture|HTMLCanvasElement|HTMLVideoElement} source - Source to create texture from
   * @return {Tiny.Texture} The newly created texture
   */
  static from(source) {
    // TODO auto detect cross origin..
    // TODO pass in scale mode?
    if (typeof source === 'string') {
      const texture = TextureCache[source];

      if (!texture) {
        // check if its a video..
        const isVideo = source.match(/\.(mp4|webm|ogg|h264|avi|mov)$/) !== null;

        if (isVideo) {
          return Texture.fromVideoUrl(source);
        }

        return Texture.fromImage(source);
      }

      return texture;
    } else if (source instanceof HTMLImageElement) {
      return new Texture(BaseTexture.from(source));
    } else if (source instanceof HTMLCanvasElement) {
      return Texture.fromCanvas(source, settings.SCALE_MODE, 'HTMLCanvasElement');
    } else if (source instanceof HTMLVideoElement) {
      return Texture.fromVideo(source);
    } else if (source instanceof BaseTexture) {
      return new Texture(source);
    }

    // lets assume its a texture!
    return source;
  }

  /**
   * Create a texture from a source and add to the cache.
   *
   * @static
   * @param {HTMLImageElement|HTMLCanvasElement} source - The input source.
   * @param {string} imageUrl - File name of texture, for cache and resolving resolution.
   * @param {string} [name] - Human readible name for the texture cache. If no name is specified, only `imageUrl` will be used as the cache ID.
   * @return {Tiny.Texture} Output texture
   */
  static fromLoader(source, imageUrl, name) {
    const baseTexture = new BaseTexture(source, undefined, getResolutionOfUrl(imageUrl));
    const texture = new Texture(baseTexture);

    baseTexture.imageUrl = imageUrl;

    // No name, use imageUrl instead
    if (!name) {
      name = imageUrl;
    }

    // lets also add the frame to the global cache for fromFrame and fromImage fucntions
    BaseTexture.addToCache(texture.baseTexture, name);
    Texture.addToCache(texture, name);

    // also add references by url if they are different.
    if (name !== imageUrl) {
      BaseTexture.addToCache(texture.baseTexture, imageUrl);
      Texture.addToCache(texture, imageUrl);
    }

    return texture;
  }

  /**
   * Adds a Texture to the global TextureCache. This cache is shared across the whole Tiny object.
   *
   * @static
   * @param {Tiny.Texture} texture - The Texture to add to the cache.
   * @param {string} id - The id that the Texture will be stored against.
   */
  static addToCache(texture, id) {
    if (id) {
      if (texture.textureCacheIds.indexOf(id) === -1) {
        texture.textureCacheIds.push(id);
      }

      /* @debug@
       if (TextureCache[id]) {
       console.warn(`Texture added to the cache with an id [${id}] that already had an entry`);
       }
       */

      TextureCache[id] = texture;
    }
  }

  /**
   * Remove a Texture from the global TextureCache.
   *
   * @static
   * @param {string|Tiny.Texture} texture - id of a Texture to be removed, or a Texture instance itself
   * @return {Tiny.Texture|null} The Texture that was removed
   */
  static removeFromCache(texture) {
    if (typeof texture === 'string') {
      const textureFromCache = TextureCache[texture];

      if (textureFromCache) {
        const index = textureFromCache.textureCacheIds.indexOf(texture);

        if (index > -1) {
          textureFromCache.textureCacheIds.splice(index, 1);
        }

        delete TextureCache[texture];

        return textureFromCache;
      }
    } else if (texture && texture.textureCacheIds) {
      for (let i = 0; i < texture.textureCacheIds.length; ++i) {
        // Check that texture matches the one being passed in before deleting it from the cache.
        if (TextureCache[texture.textureCacheIds[i]] === texture) {
          delete TextureCache[texture.textureCacheIds[i]];
        }
      }

      texture.textureCacheIds.length = 0;

      return texture;
    }

    return null;
  }

  /**
   * The frame specifies the region of the base texture that this texture uses.
   * Please call `_updateUvs()` after you change coordinates of `frame` manually.
   *
   * @member {Tiny.Rectangle}
   */
  get frame() {
    return this._frame;
  }

  set frame(frame) {
    this._frame = frame;

    this.noFrame = false;

    const { x, y, width, height } = frame;
    const xNotFit = x + width > this.baseTexture.width;
    const yNotFit = y + height > this.baseTexture.height;

    if (xNotFit || yNotFit) {
      const relationship = xNotFit && yNotFit ? 'and' : 'or';
      const errorX = `X: ${x} + ${width} = ${x + width} > ${this.baseTexture.width}`;
      const errorY = `Y: ${y} + ${height} = ${y + height} > ${this.baseTexture.height}`;

      throw new Error('Texture Error: frame does not fit inside the base Texture dimensions: ' +
        `${errorX} ${relationship} ${errorY}`);
    }

    // this.valid = width && height && this.baseTexture.source && this.baseTexture.hasLoaded;
    this.valid = width && height && this.baseTexture.hasLoaded;

    if (!this.trim && !this.rotate) {
      this.orig = frame;
    }

    if (this.valid) {
      this._updateUvs();
    }
  }

  /**
   * Indicates whether the texture is rotated inside the atlas, set to 2 to compensate for texture packer rotation, set to 6 to compensate for spine packer rotation, can be used to rotate or mirror sprites
   * See {@link Tiny.GroupD8} for explanation
   *
   * @member {number}
   */
  get rotate() {
    return this._rotate;
  }

  set rotate(rotate) {
    this._rotate = rotate;
    if (this.valid) {
      this._updateUvs();
    }
  }

  /**
   * The width of the Texture in pixels.
   *
   * @member {number}
   */
  get width() {
    return this.orig.width;
  }

  /**
   * The height of the Texture in pixels.
   *
   * @member {number}
   */
  get height() {
    return this.orig.height;
  }
}

function createWhiteTexture() {
  const canvas = document.createElement('canvas');

  canvas.width = 10;
  canvas.height = 10;

  const context = canvas.getContext('2d');

  context.fillStyle = 'white';
  context.fillRect(0, 0, 10, 10);

  return new Texture(new BaseTexture(canvas));
}

function removeAllHandlers(tex) {
  tex.destroy = function _emptyDestroy() { /* empty */ };
  tex.on = function _emptyOn() { /* empty */ };
  tex.once = function _emptyOnce() { /* empty */ };
  tex.emit = function _emptyEmit() { /* empty */ };
}

/**
 * An empty texture, used often to not have to create multiple empty textures.
 * Can not be destroyed.
 *
 * @static
 * @constant
 */
Texture.EMPTY = new Texture(new BaseTexture());
removeAllHandlers(Texture.EMPTY);
removeAllHandlers(Texture.EMPTY.baseTexture);

/**
 * A white texture of 10x10 size, used for graphics and other things
 * Can not be destroyed.
 *
 * @static
 * @constant
 */
Texture.WHITE = createWhiteTexture();
removeAllHandlers(Texture.WHITE);
removeAllHandlers(Texture.WHITE.baseTexture);
Documentation generated by JSDoc 3.4.3 on Fri Jul 09 2021 19:32:25 GMT+0800 (CST)