Refactors shared/pattern.js into core/ and display/

src/display/pattern_helper.js

@@ -0,0 +1,210 @@
+/* -*- Mode: Java; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set shiftwidth=2 tabstop=2 autoindent cindent expandtab: */
+/* Copyright 2014 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.
+ */
+/* globals CanvasGraphics, CachedCanvases, ColorSpace, Util, error, info,
+           isArray */
+
+'use strict';
+
+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;
+      }
+    };
+  }
+};
+
+ShadingIRs.Dummy = {
+  fromIR: function Dummy_fromIR() {
+    return {
+      type: 'Pattern',
+      getPattern: function Dummy_fromIR_getPattern() {
+        return 'hotpink';
+      }
+    };
+  }
+};
+
+function getShadingPatternFromIR(raw) {
+  return ShadingIRs[raw[0]].fromIR(raw);
+}
+
+var TilingPattern = (function TilingPatternClosure() {
+  var PaintType = {
+    COLORED: 1,
+    UNCOLORED: 2
+  };
+
+  var MAX_PATTERN_SIZE = 3000; // 10in @ 300dpi shall be enough
+
+  function TilingPattern(IR, color, ctx, objs, commonObjs, baseTransform) {
+    this.name = IR[1][0].name;
+    this.operatorList = IR[2];
+    this.matrix = IR[3] || [1, 0, 0, 1, 0, 0];
+    this.bbox = IR[4];
+    this.xstep = IR[5];
+    this.ystep = IR[6];
+    this.paintType = IR[7];
+    this.tilingType = IR[8];
+    this.color = color;
+    this.objs = objs;
+    this.commonObjs = commonObjs;
+    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 objs = this.objs;
+      var commonObjs = this.commonObjs;
+      var ctx = this.ctx;
+
+      info('TilingType: ' + tilingType);
+
+      var x0 = bbox[0], y0 = bbox[1], x1 = bbox[2], y1 = bbox[3];
+
+      var topLeft = [x0, y0];
+      // we want the canvas to be as large as the step size
+      var botRight = [x0 + xstep, y0 + ystep];
+
+      var width = botRight[0] - topLeft[0];
+      var height = botRight[1] - topLeft[1];
+
+      // Obtain scale from matrix and current transformation matrix.
+      var matrixScale = Util.singularValueDecompose2dScale(this.matrix);
+      var curMatrixScale = Util.singularValueDecompose2dScale(
+        this.baseTransform);
+      var combinedScale = [matrixScale[0] * curMatrixScale[0],
+        matrixScale[1] * curMatrixScale[1]];
+
+      // MAX_PATTERN_SIZE is used to avoid OOM situation.
+      // Use width and height values that are as close as possible to the end
+      // result when the pattern is used. Too low value makes the pattern look
+      // blurry. Too large value makes it look too crispy.
+      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 = CachedCanvases.getCanvas('pattern', width, height, true);
+      var tmpCtx = tmpCanvas.context;
+      var graphics = new CanvasGraphics(tmpCtx, commonObjs, objs);
+      graphics.groupLevel = owner.groupLevel;
+
+      this.setFillAndStrokeStyleToContext(tmpCtx, paintType, color);
+
+      this.setScale(width, height, xstep, ystep);
+      this.transformToScale(graphics);
+
+      // transform coordinates to pattern space
+      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 (bbox && isArray(bbox) && 4 == bbox.length) {
+        var bboxWidth = x1 - x0;
+        var bboxHeight = y1 - y0;
+        graphics.rectangle(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 rgbColor = ColorSpace.singletons.rgb.getRgb(color, 0);
+            var cssColor = Util.makeCssRgb(rgbColor);
+            context.fillStyle = cssColor;
+            context.strokeStyle = cssColor;
+            break;
+          default:
+            error('Unsupported paint type: ' + paintType);
+        }
+      },
+
+    getPattern: function TilingPattern_getPattern(ctx, owner) {
+      var temporaryPatternCanvas = this.createPatternCanvas(owner);
+
+      var ctx = this.ctx;
+      ctx.setTransform.apply(ctx, this.baseTransform);
+      ctx.transform.apply(ctx, this.matrix);
+      this.scaleToContext();
+
+      return ctx.createPattern(temporaryPatternCanvas, 'repeat');
+    }
+  };
+
+  return TilingPattern;
+})();