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// Generated by CoffeeScript 1.4.0
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/*
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  Loads an image and gives access to pixel data.
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  @class bkcore.ImageData
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  @author Thibaut 'BKcore' Despoulain <http://bkcore.com>
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*/
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(function() {
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  var ImageData, exports;
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  ImageData = (function() {
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    /*
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        Creates a new ImageData object
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        @param path string The path of the image
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        @param callback function A callback function to be called
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          once th eimage is loaded
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    */
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    function ImageData(path, callback) {
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      var _this = this;
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      this.image = new Image;
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      this.pixels = null;
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      this.canvas = null;
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      this.loaded = false;
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      this.image.onload = function() {
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        var context;
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        _this.canvas = document.createElement('canvas');
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        _this.canvas.width = _this.image.width;
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        _this.canvas.height = _this.image.height;
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        context = _this.canvas.getContext('2d');
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        context.drawImage(_this.image, 0, 0);
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        _this.pixels = context.getImageData(0, 0, _this.canvas.width, _this.canvas.height);
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        _this.loaded = true;
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        context = null;
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        _this.canvas = null;
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        _this.image = null;
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        return callback != null ? callback.call(_this) : void 0;
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      };
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      this.image.crossOrigin = "anonymous";
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      this.image.src = path;
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    }
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    /*
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        Gets pixel RGBA data at given index
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        @param x int In pixels
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        @param y int In pixels
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        @return Object{r,g,b,a}
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    */
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    ImageData.prototype.getPixel = function(x, y) {
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      var i;
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      if (!(this.pixels != null) || x < 0 || y < 0 || x >= this.pixels.width || y >= this.pixels.height) {
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        return {
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          r: 0,
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          g: 0,
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          b: 0,
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          a: 0
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        };
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      }
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      i = (y * this.pixels.width + x) * 4;
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      return {
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        r: this.pixels.data[i],
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        g: this.pixels.data[i + 1],
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        b: this.pixels.data[i + 2],
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        a: this.pixels.data[i + 3]
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      };
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    };
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    /*
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        Gets pixel RGBA data at given float index using bilinear interpolation
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        @param x float In subpixels
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        @param y float In subpixels
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        @return Object{r,g,b,a}
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    */
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    ImageData.prototype.getPixelBilinear = function(fx, fy) {
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      var ax, ay, c, cf1, cf2, cx, cxy, cy, dx, dy, rx, ry, x, y;
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      x = Math.floor(fx);
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      y = Math.floor(fy);
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      rx = fx - x - .5;
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      ry = fy - y - .5;
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      ax = Math.abs(rx);
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      ay = Math.abs(ry);
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      dx = rx < 0 ? -1 : 1;
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      dy = ry < 0 ? -1 : 1;
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      c = this.getPixel(x, y);
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      cx = this.getPixel(x + dx, y);
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      cy = this.getPixel(x, y + dy);
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      cxy = this.getPixel(x + dx, y + dy);
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      cf1 = [(1 - ax) * c.r + ax * cx.r, (1 - ax) * c.g + ax * cx.g, (1 - ax) * c.b + ax * cx.b, (1 - ax) * c.a + ax * cx.a];
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      cf2 = [(1 - ax) * cy.r + ax * cxy.r, (1 - ax) * cy.g + ax * cxy.g, (1 - ax) * cy.b + ax * cxy.b, (1 - ax) * cy.a + ax * cxy.a];
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      return {
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        r: (1 - ay) * cf1[0] + ay * cf2[0],
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        g: (1 - ay) * cf1[1] + ay * cf2[1],
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        b: (1 - ay) * cf1[2] + ay * cf2[2],
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        a: (1 - ay) * cf1[3] + ay * cf2[3]
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      };
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    };
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    /*
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        Gets pixel data at given index
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        as 3-bytes integer (for floating-point textures erzats, from RGB values)
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        @param x int In pixels
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        @param y int In pixels
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        @return int (R + G*255 + B*255*255)
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    */
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    ImageData.prototype.getPixelF = function(x, y) {
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      var c;
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      c = this.getPixel(x, y);
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      return c.r + c.g * 255 + c.b * 255 * 255;
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    };
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    /*
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        Gets pixel data at given float index using bilinear interpolationas
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        as 3-bytes integer (for floating-point textures erzats, from RGB values)
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        @param x float In subpixels
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        @param y float In subpixels
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        @return Object{r,g,b,a}
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    */
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    ImageData.prototype.getPixelFBilinear = function(fx, fy) {
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      var c;
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      c = this.getPixelBilinear(fx, fy);
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      return c.r + c.g * 255 + c.b * 255 * 255;
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    };
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    return ImageData;
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  })();
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  /*
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    Exports
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    @package bkcore
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  */
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  exports = exports != null ? exports : this;
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  exports.bkcore || (exports.bkcore = {});
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  exports.bkcore.ImageData = ImageData;
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}).call(this);
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