pdfjs-dist/lib/display/pattern_helper.js

/* Copyright 2017 Mozilla Foundation
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
'use strict';
var sharedUtil = require('../shared/util.js');
var displayWebGL = require('./webgl.js');
var Util = sharedUtil.Util;
var info = sharedUtil.info;
var isArray = sharedUtil.isArray;
var error = sharedUtil.error;
var WebGLUtils = displayWebGL.WebGLUtils;
var ShadingIRs = {};
ShadingIRs.RadialAxial = {
 fromIR: function RadialAxial_fromIR(raw) {
  var type = raw[1];
  var colorStops = raw[2];
  var p0 = raw[3];
  var p1 = raw[4];
  var r0 = raw[5];
  var r1 = raw[6];
  return {
   type: 'Pattern',
   getPattern: function RadialAxial_getPattern(ctx) {
    var grad;
    if (type === 'axial') {
     grad = ctx.createLinearGradient(p0[0], p0[1], p1[0], p1[1]);
    } else if (type === 'radial') {
     grad = ctx.createRadialGradient(p0[0], p0[1], r0, p1[0], p1[1], r1);
    }
    for (var i = 0, ii = colorStops.length; i < ii; ++i) {
     var c = colorStops[i];
     grad.addColorStop(c[0], c[1]);
    }
    return grad;
   }
  };
 }
};
var createMeshCanvas = function createMeshCanvasClosure() {
 function drawTriangle(data, context, p1, p2, p3, c1, c2, c3) {
  var coords = context.coords, colors = context.colors;
  var bytes = data.data, rowSize = data.width * 4;
  var tmp;
  if (coords[p1 + 1] > coords[p2 + 1]) {
   tmp = p1;
   p1 = p2;
   p2 = tmp;
   tmp = c1;
   c1 = c2;
   c2 = tmp;
  }
  if (coords[p2 + 1] > coords[p3 + 1]) {
   tmp = p2;
   p2 = p3;
   p3 = tmp;
   tmp = c2;
   c2 = c3;
   c3 = tmp;
  }
  if (coords[p1 + 1] > coords[p2 + 1]) {
   tmp = p1;
   p1 = p2;
   p2 = tmp;
   tmp = c1;
   c1 = c2;
   c2 = tmp;
  }
  var x1 = (coords[p1] + context.offsetX) * context.scaleX;
  var y1 = (coords[p1 + 1] + context.offsetY) * context.scaleY;
  var x2 = (coords[p2] + context.offsetX) * context.scaleX;
  var y2 = (coords[p2 + 1] + context.offsetY) * context.scaleY;
  var x3 = (coords[p3] + context.offsetX) * context.scaleX;
  var y3 = (coords[p3 + 1] + context.offsetY) * context.scaleY;
  if (y1 >= y3) {
   return;
  }
  var c1r = colors[c1], c1g = colors[c1 + 1], c1b = colors[c1 + 2];
  var c2r = colors[c2], c2g = colors[c2 + 1], c2b = colors[c2 + 2];
  var c3r = colors[c3], c3g = colors[c3 + 1], c3b = colors[c3 + 2];
  var minY = Math.round(y1), maxY = Math.round(y3);
  var xa, car, cag, cab;
  var xb, cbr, cbg, cbb;
  var k;
  for (var y = minY; y <= maxY; y++) {
   if (y < y2) {
    k = y < y1 ? 0 : y1 === y2 ? 1 : (y1 - y) / (y1 - y2);
    xa = x1 - (x1 - x2) * k;
    car = c1r - (c1r - c2r) * k;
    cag = c1g - (c1g - c2g) * k;
    cab = c1b - (c1b - c2b) * k;
   } else {
    k = y > y3 ? 1 : y2 === y3 ? 0 : (y2 - y) / (y2 - y3);
    xa = x2 - (x2 - x3) * k;
    car = c2r - (c2r - c3r) * k;
    cag = c2g - (c2g - c3g) * k;
    cab = c2b - (c2b - c3b) * k;
   }
   k = y < y1 ? 0 : y > y3 ? 1 : (y1 - y) / (y1 - y3);
   xb = x1 - (x1 - x3) * k;
   cbr = c1r - (c1r - c3r) * k;
   cbg = c1g - (c1g - c3g) * k;
   cbb = c1b - (c1b - c3b) * k;
   var x1_ = Math.round(Math.min(xa, xb));
   var x2_ = Math.round(Math.max(xa, xb));
   var j = rowSize * y + x1_ * 4;
   for (var x = x1_; x <= x2_; x++) {
    k = (xa - x) / (xa - xb);
    k = k < 0 ? 0 : k > 1 ? 1 : k;
    bytes[j++] = car - (car - cbr) * k | 0;
    bytes[j++] = cag - (cag - cbg) * k | 0;
    bytes[j++] = cab - (cab - cbb) * k | 0;
    bytes[j++] = 255;
   }
  }
 }
 function drawFigure(data, figure, context) {
  var ps = figure.coords;
  var cs = figure.colors;
  var i, ii;
  switch (figure.type) {
  case 'lattice':
   var verticesPerRow = figure.verticesPerRow;
   var rows = Math.floor(ps.length / verticesPerRow) - 1;
   var cols = verticesPerRow - 1;
   for (i = 0; i < rows; i++) {
    var q = i * verticesPerRow;
    for (var j = 0; j < cols; j++, q++) {
     drawTriangle(data, context, ps[q], ps[q + 1], ps[q + verticesPerRow], cs[q], cs[q + 1], cs[q + verticesPerRow]);
     drawTriangle(data, context, ps[q + verticesPerRow + 1], ps[q + 1], ps[q + verticesPerRow], cs[q + verticesPerRow + 1], cs[q + 1], cs[q + verticesPerRow]);
    }
   }
   break;
  case 'triangles':
   for (i = 0, ii = ps.length; i < ii; i += 3) {
    drawTriangle(data, context, ps[i], ps[i + 1], ps[i + 2], cs[i], cs[i + 1], cs[i + 2]);
   }
   break;
  default:
   error('illigal figure');
   break;
  }
 }
 function createMeshCanvas(bounds, combinesScale, coords, colors, figures, backgroundColor, cachedCanvases) {
  var EXPECTED_SCALE = 1.1;
  var MAX_PATTERN_SIZE = 3000;
  var BORDER_SIZE = 2;
  var offsetX = Math.floor(bounds[0]);
  var offsetY = Math.floor(bounds[1]);
  var boundsWidth = Math.ceil(bounds[2]) - offsetX;
  var boundsHeight = Math.ceil(bounds[3]) - offsetY;
  var width = Math.min(Math.ceil(Math.abs(boundsWidth * combinesScale[0] * EXPECTED_SCALE)), MAX_PATTERN_SIZE);
  var height = Math.min(Math.ceil(Math.abs(boundsHeight * combinesScale[1] * EXPECTED_SCALE)), MAX_PATTERN_SIZE);
  var scaleX = boundsWidth / width;
  var scaleY = boundsHeight / height;
  var context = {
   coords: coords,
   colors: colors,
   offsetX: -offsetX,
   offsetY: -offsetY,
   scaleX: 1 / scaleX,
   scaleY: 1 / scaleY
  };
  var paddedWidth = width + BORDER_SIZE * 2;
  var paddedHeight = height + BORDER_SIZE * 2;
  var canvas, tmpCanvas, i, ii;
  if (WebGLUtils.isEnabled) {
   canvas = WebGLUtils.drawFigures(width, height, backgroundColor, figures, context);
   tmpCanvas = cachedCanvases.getCanvas('mesh', paddedWidth, paddedHeight, false);
   tmpCanvas.context.drawImage(canvas, BORDER_SIZE, BORDER_SIZE);
   canvas = tmpCanvas.canvas;
  } else {
   tmpCanvas = cachedCanvases.getCanvas('mesh', paddedWidth, paddedHeight, false);
   var tmpCtx = tmpCanvas.context;
   var data = tmpCtx.createImageData(width, height);
   if (backgroundColor) {
    var bytes = data.data;
    for (i = 0, ii = bytes.length; i < ii; i += 4) {
     bytes[i] = backgroundColor[0];
     bytes[i + 1] = backgroundColor[1];
     bytes[i + 2] = backgroundColor[2];
     bytes[i + 3] = 255;
    }
   }
   for (i = 0; i < figures.length; i++) {
    drawFigure(data, figures[i], context);
   }
   tmpCtx.putImageData(data, BORDER_SIZE, BORDER_SIZE);
   canvas = tmpCanvas.canvas;
  }
  return {
   canvas: canvas,
   offsetX: offsetX - BORDER_SIZE * scaleX,
   offsetY: offsetY - BORDER_SIZE * scaleY,
   scaleX: scaleX,
   scaleY: scaleY
  };
 }
 return createMeshCanvas;
}();
ShadingIRs.Mesh = {
 fromIR: function Mesh_fromIR(raw) {
  var coords = raw[2];
  var colors = raw[3];
  var figures = raw[4];
  var bounds = raw[5];
  var matrix = raw[6];
  var background = raw[8];
  return {
   type: 'Pattern',
   getPattern: function Mesh_getPattern(ctx, owner, shadingFill) {
    var scale;
    if (shadingFill) {
     scale = Util.singularValueDecompose2dScale(ctx.mozCurrentTransform);
    } else {
     scale = Util.singularValueDecompose2dScale(owner.baseTransform);
     if (matrix) {
      var matrixScale = Util.singularValueDecompose2dScale(matrix);
      scale = [
       scale[0] * matrixScale[0],
       scale[1] * matrixScale[1]
      ];
     }
    }
    var temporaryPatternCanvas = createMeshCanvas(bounds, scale, coords, colors, figures, shadingFill ? null : background, owner.cachedCanvases);
    if (!shadingFill) {
     ctx.setTransform.apply(ctx, owner.baseTransform);
     if (matrix) {
      ctx.transform.apply(ctx, matrix);
     }
    }
    ctx.translate(temporaryPatternCanvas.offsetX, temporaryPatternCanvas.offsetY);
    ctx.scale(temporaryPatternCanvas.scaleX, temporaryPatternCanvas.scaleY);
    return ctx.createPattern(temporaryPatternCanvas.canvas, 'no-repeat');
   }
  };
 }
};
ShadingIRs.Dummy = {
 fromIR: function Dummy_fromIR() {
  return {
   type: 'Pattern',
   getPattern: function Dummy_fromIR_getPattern() {
    return 'hotpink';
   }
  };
 }
};
function getShadingPatternFromIR(raw) {
 var shadingIR = ShadingIRs[raw[0]];
 if (!shadingIR) {
  error('Unknown IR type: ' + raw[0]);
 }
 return shadingIR.fromIR(raw);
}
var TilingPattern = function TilingPatternClosure() {
 var PaintType = {
  COLORED: 1,
  UNCOLORED: 2
 };
 var MAX_PATTERN_SIZE = 3000;
 function TilingPattern(IR, color, ctx, canvasGraphicsFactory, baseTransform) {
  this.operatorList = IR[2];
  this.matrix = IR[3] || [
   1,
   0,
   0,
   1,
   0,
   0
  ];
  this.bbox = Util.normalizeRect(IR[4]);
  this.xstep = IR[5];
  this.ystep = IR[6];
  this.paintType = IR[7];
  this.tilingType = IR[8];
  this.color = color;
  this.canvasGraphicsFactory = canvasGraphicsFactory;
  this.baseTransform = baseTransform;
  this.type = 'Pattern';
  this.ctx = ctx;
 }
 TilingPattern.prototype = {
  createPatternCanvas: function TilinPattern_createPatternCanvas(owner) {
   var operatorList = this.operatorList;
   var bbox = this.bbox;
   var xstep = this.xstep;
   var ystep = this.ystep;
   var paintType = this.paintType;
   var tilingType = this.tilingType;
   var color = this.color;
   var canvasGraphicsFactory = this.canvasGraphicsFactory;
   info('TilingType: ' + tilingType);
   var x0 = bbox[0], y0 = bbox[1], x1 = bbox[2], y1 = bbox[3];
   var topLeft = [
    x0,
    y0
   ];
   var botRight = [
    x0 + xstep,
    y0 + ystep
   ];
   var width = botRight[0] - topLeft[0];
   var height = botRight[1] - topLeft[1];
   var matrixScale = Util.singularValueDecompose2dScale(this.matrix);
   var curMatrixScale = Util.singularValueDecompose2dScale(this.baseTransform);
   var combinedScale = [
    matrixScale[0] * curMatrixScale[0],
    matrixScale[1] * curMatrixScale[1]
   ];
   width = Math.min(Math.ceil(Math.abs(width * combinedScale[0])), MAX_PATTERN_SIZE);
   height = Math.min(Math.ceil(Math.abs(height * combinedScale[1])), MAX_PATTERN_SIZE);
   var tmpCanvas = owner.cachedCanvases.getCanvas('pattern', width, height, true);
   var tmpCtx = tmpCanvas.context;
   var graphics = canvasGraphicsFactory.createCanvasGraphics(tmpCtx);
   graphics.groupLevel = owner.groupLevel;
   this.setFillAndStrokeStyleToContext(tmpCtx, paintType, color);
   this.setScale(width, height, xstep, ystep);
   this.transformToScale(graphics);
   var tmpTranslate = [
    1,
    0,
    0,
    1,
    -topLeft[0],
    -topLeft[1]
   ];
   graphics.transform.apply(graphics, tmpTranslate);
   this.clipBbox(graphics, bbox, x0, y0, x1, y1);
   graphics.executeOperatorList(operatorList);
   return tmpCanvas.canvas;
  },
  setScale: function TilingPattern_setScale(width, height, xstep, ystep) {
   this.scale = [
    width / xstep,
    height / ystep
   ];
  },
  transformToScale: function TilingPattern_transformToScale(graphics) {
   var scale = this.scale;
   var tmpScale = [
    scale[0],
    0,
    0,
    scale[1],
    0,
    0
   ];
   graphics.transform.apply(graphics, tmpScale);
  },
  scaleToContext: function TilingPattern_scaleToContext() {
   var scale = this.scale;
   this.ctx.scale(1 / scale[0], 1 / scale[1]);
  },
  clipBbox: function clipBbox(graphics, bbox, x0, y0, x1, y1) {
   if (isArray(bbox) && bbox.length === 4) {
    var bboxWidth = x1 - x0;
    var bboxHeight = y1 - y0;
    graphics.ctx.rect(x0, y0, bboxWidth, bboxHeight);
    graphics.clip();
    graphics.endPath();
   }
  },
  setFillAndStrokeStyleToContext: function setFillAndStrokeStyleToContext(context, paintType, color) {
   switch (paintType) {
   case PaintType.COLORED:
    var ctx = this.ctx;
    context.fillStyle = ctx.fillStyle;
    context.strokeStyle = ctx.strokeStyle;
    break;
   case PaintType.UNCOLORED:
    var cssColor = Util.makeCssRgb(color[0], color[1], color[2]);
    context.fillStyle = cssColor;
    context.strokeStyle = cssColor;
    break;
   default:
    error('Unsupported paint type: ' + paintType);
   }
  },
  getPattern: function TilingPattern_getPattern(ctx, owner) {
   var temporaryPatternCanvas = this.createPatternCanvas(owner);
   ctx = this.ctx;
   ctx.setTransform.apply(ctx, this.baseTransform);
   ctx.transform.apply(ctx, this.matrix);
   this.scaleToContext();
   return ctx.createPattern(temporaryPatternCanvas, 'repeat');
  }
 };
 return TilingPattern;
}();
exports.getShadingPatternFromIR = getShadingPatternFromIR;
exports.TilingPattern = TilingPattern;