From fe7c8b52f645e60c5569f319fa52e074813d53c7 Mon Sep 17 00:00:00 2001
From: Julian Viereck <julian.viereck@gmail.com>
Date: Wed, 22 Jun 2011 14:25:21 +0200
Subject: [PATCH] Add very simple GradientProxy support - makes page 11 render.

---
 canvas_proxy.js    | 35 +++++++++++++++++++++++++++++++++--
 viewer_worker.html | 19 ++++++++++++++++++-
 2 files changed, 51 insertions(+), 3 deletions(-)

diff --git a/canvas_proxy.js b/canvas_proxy.js
index c7234d9c9..0670762e5 100644
--- a/canvas_proxy.js
+++ b/canvas_proxy.js
@@ -51,6 +51,16 @@ var JpegStreamProxy = (function() {
     return constructor;
 })();
 
+// Really simple GradientProxy. There is currently only one active gradient at
+// the time, meaning you can't create a gradient, create a second one and then
+// use the first one again. As this isn't used in pdf.js right now, it's okay.
+function GradientProxy(stack, x0, y0, x1, y1) {
+    stack.push(["$createLinearGradient", [x0, y0, x1, y1]]);
+    this.addColorStop = function(i, rgba) {
+        stack.push(["$addColorStop", [i, rgba]]);
+    }
+}
+
 function CanvasProxy(width, height) {
     var stack = this.$stack = [];
 
@@ -79,7 +89,7 @@ function CanvasProxy(width, height) {
         "translate",
         "transform",
         "setTransform",
-        "createLinearGradient",
+        // "createLinearGradient",
         "createPattern",
         "clearRect",
         "fillRect",
@@ -104,6 +114,10 @@ function CanvasProxy(width, height) {
         "$showText"
     ];
 
+    this.createLinearGradient = function(x0, y0, x1, y1) {
+        return new GradientProxy(stack, x0, y0, x1, y1);
+    }
+
     this.drawImage = function(image, x, y, width, height, sx, sy, swidth, sheight) {
         if (image instanceof ImageCanvasProxy) {
             stack.push(["$drawCanvas", [image.imgData, x, y, image.width, image.height]]);
@@ -168,7 +182,24 @@ function CanvasProxy(width, height) {
     for (var name in ctxProp) {
         this["$" + name] = ctxProp[name];
         this.__defineGetter__(name, buildGetter(name));
-        this.__defineSetter__(name, buildSetter(name));
+
+        // Special treatment for `fillStyle` and `strokeStyle`: The passed style
+        // might be a gradient. Need to check for that.
+        if (name == "fillStyle" || name == "strokeStyle") {
+            function buildSetterStyle(name) {
+                return function(value) {
+                    if (value instanceof GradientProxy) {
+                        stack.push(["$" + name + "Gradient"]);
+                    } else {
+                        stack.push(["$", name, value]);
+                        return this["$" + name] = value;
+                    }
+                }
+            }
+            this.__defineSetter__(name, buildSetterStyle(name));
+        } else {
+            this.__defineSetter__(name, buildSetter(name));
+        }
     }
 }
 
diff --git a/viewer_worker.html b/viewer_worker.html
index fd436db75..83c41e6e0 100644
--- a/viewer_worker.html
+++ b/viewer_worker.html
@@ -14,6 +14,7 @@ function toc(msg) {
 
 var myWorker = new Worker('worker.js');
 var images = {};
+var gradient;
 
 var currentX = 0;
 var currentXStack = [];
@@ -57,6 +58,22 @@ var special = {
         }
         ctx.drawImage(image, x, y, image.width, image.height,
             sx, sy, swidth, sheight);
+    },
+
+    "$createLinearGradient": function(x0, y0, x1, y1) {
+        gradient = ctx.createLinearGradient(x0, y0, x1, y1);
+    },
+
+    "$addColorStop": function(i, rgba) {
+        gradient.addColorStop(i, rgba);
+    },
+
+    "$fillStyleGradient": function() {
+        ctx.fillStyle = gradient;
+    },
+
+    "$strokeStyleGradient": function() {
+        ctx.strokeStyle = gradient;
     }
 }
 
@@ -196,7 +213,7 @@ function open(url) {
         var data = req.mozResponseArrayBuffer || req.mozResponse ||
                    req.responseArrayBuffer || req.response;
         myWorker.postMessage(data);
-        showPage("1");
+        showPage("11");
       }
     };
     req.send(null);