Source: tiny/core/sprites/Sprite.js

import { Point, ObservablePoint, Rectangle } from '../math';
import { TextureCache } from '../utils';
import { BLEND_MODES } from '../const';
import Texture from '../textures/Texture';
import Container from '../display/Container';

const tempPoint = new Point();

/**
 * The Sprite object is the base for all textured objects that are rendered to the screen
 *
 * A sprite can be created directly from an image like this:
 *
 *  ```js
 *  let sprite = new Tiny.Sprite.fromImage('assets/image.png');
 *  ```
 *
 * @class
 * @extends Tiny.Container
 * @memberof Tiny
 */
export default class Sprite extends Container {
  /**
   * @param {Tiny.Texture} texture - The texture for this sprite
   */
  constructor(texture) {
    super();

    /**
     * The anchor sets the origin point of the texture.
     * The default is 0,0 or taken from the {@link Tiny.Texture#defaultAnchor|Texture} passed to the constructor. A value of 0,0 means the texture's origin is the top left.
     * Setting the anchor to 0.5,0.5 means the texture's origin is centered.
     * Setting the anchor to 1,1 would mean the texture's origin point will be the bottom right corner.
     * Note: Updating the {@link Tiny.Texture#defaultAnchor} after a Texture is created does _not_ update the Sprite's anchor values.
     *
     * @member {Tiny.ObservablePoint}
     * @private
     */
    this._anchor = new ObservablePoint(
      this._onAnchorUpdate,
      this,
      (texture ? texture.defaultAnchor.x : 0),
      (texture ? texture.defaultAnchor.y : 0)
    );

    /**
     * The texture that the sprite is using
     *
     * @private
     * @member {Tiny.Texture}
     */
    this._texture = null;

    /**
     * The width of the sprite (this is initially set by the texture)
     *
     * @private
     * @member {number}
     */
    this._width = 0;

    /**
     * The height of the sprite (this is initially set by the texture)
     *
     * @private
     * @member {number}
     */
    this._height = 0;

    /**
     * The tint applied to the sprite. This is a hex value. A value of 0xFFFFFF will remove any tint effect.
     *
     * @private
     * @member {number}
     * @default 0xFFFFFF
     */
    this._tint = null;
    this._tintRGB = null;
    this.tint = 0xFFFFFF;

    /**
     * The blend mode to be applied to the sprite. Apply a value of `Tiny.BLEND_MODES.NORMAL` to reset the blend mode.
     *
     * @member {number}
     * @default Tiny.BLEND_MODES.NORMAL
     * @see Tiny.BLEND_MODES
     */
    this.blendMode = BLEND_MODES.NORMAL;

    /**
     * The shader that will be used to render the sprite. Set to null to remove a current shader.
     *
     * @member {Tiny.Filter|Tiny.Shader}
     */
    this.shader = null;

    /**
     * An internal cached value of the tint.
     *
     * @private
     * @member {number}
     * @default 0xFFFFFF
     */
    this.cachedTint = 0xFFFFFF;

    // call texture setter
    this.texture = texture || Texture.EMPTY;

    /**
     * this is used to store the vertex data of the sprite (basically a quad)
     *
     * @private
     * @member {Float32Array}
     */
    this.vertexData = new Float32Array(8);

    /**
     * This is used to calculate the bounds of the object IF it is a trimmed sprite
     *
     * @private
     * @member {Float32Array}
     */
    this.vertexTrimmedData = null;

    this._transformID = -1;
    this._textureID = -1;

    this._transformTrimmedID = -1;
    this._textureTrimmedID = -1;

    /**
     * Plugin that is responsible for rendering this element.
     * Allows to customize the rendering process without overriding '_renderWebGL' & '_renderCanvas' methods.
     *
     * @member {string}
     * @default 'sprite'
     */
    this.pluginName = 'sprite';
  }

  /**
   * When the texture is updated, this event will fire to update the scale and frame
   *
   * @private
   */
  _onTextureUpdate() {
    this._textureID = -1;
    this._textureTrimmedID = -1;
    this.cachedTint = 0xFFFFFF;

    // so if _width is 0 then width was not set..
    if (this._width) {
      this.scale.x = Math.sign(this.scale.x) * this._width / this._texture.orig.width;
    }

    if (this._height) {
      this.scale.y = Math.sign(this.scale.y) * this._height / this._texture.orig.height;
    }
  }

  /**
   * Called when the anchor position updates.
   *
   * @private
   */
  _onAnchorUpdate() {
    this._transformID = -1;
    this._transformTrimmedID = -1;
  }

  /**
   * calculates worldTransform * vertices, store it in vertexData
   */
  calculateVertices() {
    if (this._transformID === this.transform._worldID && this._textureID === this._texture._updateID) {
      return;
    }

    this._transformID = this.transform._worldID;
    this._textureID = this._texture._updateID;

    // set the vertex data

    const texture = this._texture;
    const wt = this.transform.worldTransform;
    const a = wt.a;
    const b = wt.b;
    const c = wt.c;
    const d = wt.d;
    const tx = wt.tx;
    const ty = wt.ty;
    const vertexData = this.vertexData;
    const trim = texture.trim;
    const orig = texture.orig;
    const anchor = this._anchor;

    let w0 = 0;
    let w1 = 0;
    let h0 = 0;
    let h1 = 0;

    if (trim) {
      // if the sprite is trimmed and is not a tilingsprite then we need to add the extra
      // space before transforming the sprite coords.
      w1 = trim.x - (anchor._x * orig.width);
      w0 = w1 + trim.width;

      h1 = trim.y - (anchor._y * orig.height);
      h0 = h1 + trim.height;
    } else {
      w1 = -anchor._x * orig.width;
      w0 = w1 + orig.width;

      h1 = -anchor._y * orig.height;
      h0 = h1 + orig.height;
    }

    // xy
    vertexData[0] = (a * w1) + (c * h1) + tx;
    vertexData[1] = (d * h1) + (b * w1) + ty;

    // xy
    vertexData[2] = (a * w0) + (c * h1) + tx;
    vertexData[3] = (d * h1) + (b * w0) + ty;

    // xy
    vertexData[4] = (a * w0) + (c * h0) + tx;
    vertexData[5] = (d * h0) + (b * w0) + ty;

    // xy
    vertexData[6] = (a * w1) + (c * h0) + tx;
    vertexData[7] = (d * h0) + (b * w1) + ty;
  }

  /**
   * calculates worldTransform * vertices for a non texture with a trim. store it in vertexTrimmedData
   * This is used to ensure that the true width and height of a trimmed texture is respected
   */
  calculateTrimmedVertices() {
    if (!this.vertexTrimmedData) {
      this.vertexTrimmedData = new Float32Array(8);
    } else if (this._transformTrimmedID === this.transform._worldID && this._textureTrimmedID === this._texture._updateID) {
      return;
    }

    this._transformTrimmedID = this.transform._worldID;
    this._textureTrimmedID = this._texture._updateID;

    // lets do some special trim code!
    const texture = this._texture;
    const vertexData = this.vertexTrimmedData;
    const orig = texture.orig;
    const anchor = this._anchor;

    // lets calculate the new untrimmed bounds..
    const wt = this.transform.worldTransform;
    const a = wt.a;
    const b = wt.b;
    const c = wt.c;
    const d = wt.d;
    const tx = wt.tx;
    const ty = wt.ty;

    const w1 = -anchor._x * orig.width;
    const w0 = w1 + orig.width;

    const h1 = -anchor._y * orig.height;
    const h0 = h1 + orig.height;

    // xy
    vertexData[0] = (a * w1) + (c * h1) + tx;
    vertexData[1] = (d * h1) + (b * w1) + ty;

    // xy
    vertexData[2] = (a * w0) + (c * h1) + tx;
    vertexData[3] = (d * h1) + (b * w0) + ty;

    // xy
    vertexData[4] = (a * w0) + (c * h0) + tx;
    vertexData[5] = (d * h0) + (b * w0) + ty;

    // xy
    vertexData[6] = (a * w1) + (c * h0) + tx;
    vertexData[7] = (d * h0) + (b * w1) + ty;
  }

  /**
   *
   * Renders the object using the WebGL renderer
   *
   * @private
   * @param {Tiny.WebGLRenderer} renderer - The webgl renderer to use.
   */
  _renderWebGL(renderer) {
    this.calculateVertices();

    renderer.setObjectRenderer(renderer.plugins[this.pluginName]);
    renderer.plugins[this.pluginName].render(this);
  }

  /**
   * Renders the object using the Canvas renderer
   *
   * @private
   * @param {Tiny.CanvasRenderer} renderer - The renderer
   */
  _renderCanvas(renderer) {
    renderer.plugins[this.pluginName].render(this);
  }

  /**
   * Updates the bounds of the sprite.
   *
   * @private
   */
  _calculateBounds() {
    const trim = this._texture.trim;
    const orig = this._texture.orig;

    // First lets check to see if the current texture has a trim..
    if (!trim || (trim.width === orig.width && trim.height === orig.height)) {
      // no trim! lets use the usual calculations..
      this.calculateVertices();
      this._bounds.addQuad(this.vertexData);
    } else {
      // lets calculate a special trimmed bounds...
      this.calculateTrimmedVertices();
      this._bounds.addQuad(this.vertexTrimmedData);
    }
  }

  /**
   * Gets the local bounds of the sprite object.
   *
   * @param {Tiny.Rectangle} rect - The output rectangle.
   * @return {Tiny.Rectangle} The bounds.
   */
  getLocalBounds(rect) {
    // we can do a fast local bounds if the sprite has no children!
    if (this.children.length === 0) {
      this._bounds.minX = this._texture.orig.width * -this._anchor._x;
      this._bounds.minY = this._texture.orig.height * -this._anchor._y;
      this._bounds.maxX = this._texture.orig.width * (1 - this._anchor._x);
      this._bounds.maxY = this._texture.orig.height * (1 - this._anchor._y);

      if (!rect) {
        if (!this._localBoundsRect) {
          this._localBoundsRect = new Rectangle();
        }

        rect = this._localBoundsRect;
      }

      return this._bounds.getRectangle(rect);
    }

    return super.getLocalBounds.call(this, rect);
  }

  /**
   * Tests if a point is inside this sprite
   *
   * @param {Tiny.Point} point - the point to test
   * @return {boolean} the result of the test
   */
  containsPoint(point) {
    this.worldTransform.applyInverse(point, tempPoint);

    const width = this._texture.orig.width;
    const height = this._texture.orig.height;
    const x1 = -width * this.anchor.x;
    let y1 = 0;

    if (tempPoint.x >= x1 && tempPoint.x < x1 + width) {
      y1 = -height * this.anchor.y;

      if (tempPoint.y >= y1 && tempPoint.y < y1 + height) {
        return true;
      }
    }

    return false;
  }

  /**
   * Destroys this sprite and optionally its texture and children
   *
   * @param {object|boolean} [options] - Options parameter. A boolean will act as if all options have been set to that value
   * @param {boolean} [options.children=false] - If set to true, all the children will have their destroy method called as well. 'options' will be passed on to those calls.
   * @param {boolean} [options.texture=false] - Should it destroy the current texture of the sprite as well
   * @param {boolean} [options.baseTexture=false] - Should it destroy the base texture of the sprite as well
   */
  destroy(options) {
    super.destroy(options);

    // @version 1.2.3 @2018-01-03 修复重复调用精灵对象的 destroy 方法导致找不到 this._texture 对象
    this._texture && this._texture.off('update', this._onTextureUpdate, this);

    this._anchor = null;

    const destroyTexture = typeof options === 'boolean' ? options : options && options.texture;

    if (destroyTexture && this._texture) {
      const destroyBaseTexture = typeof options === 'boolean' ? options : options && options.baseTexture;

      this._texture.destroy(!!destroyBaseTexture);
    }

    this._texture = null;
    this.shader = null;
  }

  // some helper functions..

  /**
   * Helper function that creates a new sprite 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.Sprite} The newly created texture
   */
  static from(source) {
    return new Sprite(Texture.from(source));
  }

  /**
   * 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.Sprite} A new Sprite using a texture from the texture cache matching the frameId
   */
  static fromFrame(frameId) {
    const texture = TextureCache[frameId];

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

    return new Sprite(texture);
  }

  /**
   * Helper function that creates a sprite that will contain a texture based on an image url
   * If the image is not in the texture cache it will be loaded
   *
   * @static
   * @param {string} imageId - The image url of the texture
   * @param {boolean} [crossorigin=(auto)] - if you want to specify the cross-origin parameter
   * @param {number} [scaleMode=Tiny.settings.SCALE_MODE] - if you want to specify the scale mode,
   *  see {@link Tiny.SCALE_MODES} for possible values
   * @return {Tiny.Sprite} A new Sprite using a texture from the texture cache matching the image id
   */
  static fromImage(imageId, crossorigin, scaleMode) {
    return new Sprite(Texture.fromImage(imageId, crossorigin, scaleMode));
  }

  /**
   *
   * @param x
   * @param y
   */
  setAnchor(x, y) {
    this.anchor.set(x, y === void 0 ? x : y);
  }

  /**
   *
   * @return {object}
   */
  getAnchor() {
    return this.anchor;
  }

  /**
   * The width of the sprite, setting this will actually modify the scale to achieve the value set
   *
   * @member {number}
   */
  get width() {
    return Math.abs(this.scale.x) * this._texture.orig.width;
  }

  set width(value) {
    const s = Math.sign(this.scale.x) || 1;

    this.scale.x = s * value / this._texture.orig.width;
    this._width = value;
  }

  /**
   * The height of the sprite, setting this will actually modify the scale to achieve the value set
   *
   * @member {number}
   */
  get height() {
    return Math.abs(this.scale.y) * this._texture.orig.height;
  }

  set height(value) {
    const s = Math.sign(this.scale.y) || 1;

    this.scale.y = s * value / this._texture.orig.height;
    this._height = value;
  }

  /**
   * The anchor sets the origin point of the texture.
   * The default is 0,0 or taken from the {@link Tiny.Texture|Texture} passed to the constructor.
   * Setting the texture at a later point of time does not change the anchor.
   *
   * 0,0 means the texture's origin is the top left, 0.5,0.5 is the center, 1,1 the bottom right corner.
   *
   * @member {Tiny.ObservablePoint}
   */
  get anchor() {
    return this._anchor;
  }

  set anchor(value) {
    this._anchor.copy(value);
  }

  /**
   * The tint applied to the sprite. This is a hex value.
   * A value of 0xFFFFFF will remove any tint effect.
   *
   * @member {number}
   * @default 0xFFFFFF
   */
  get tint() {
    return this._tint;
  }

  set tint(value) {
    this._tint = value;
    this._tintRGB = (value >> 16) + (value & 0xff00) + ((value & 0xff) << 16);
  }

  /**
   * The texture that the sprite is using
   *
   * @member {Tiny.Texture}
   */
  get texture() {
    return this._texture;
  }

  set texture(value) {
    if (this._texture === value) {
      return;
    }

    this._texture = value || Texture.EMPTY;
    this.cachedTint = 0xFFFFFF;

    this._textureID = -1;
    this._textureTrimmedID = -1;

    if (value) {
      // wait for the texture to load
      if (value.baseTexture.hasLoaded) {
        this._onTextureUpdate();
      } else {
        value.once('update', this._onTextureUpdate, this);
      }
    }
  }
}
Documentation generated by JSDoc 3.4.3 on Mon May 25 2020 18:08:44 GMT+0800 (CST)