From 7336835d3c5e0e779a61dc1e5dbfef4484416eaf Mon Sep 17 00:00:00 2001
From: Tj Holowaychuk <tj@vision-media.ca>
Date: Tue, 5 Oct 2010 15:11:47 -0700
Subject: [PATCH] Added setTransform(). Closes #15

---
 lib/canvas.js    |  5 +++++
 src/context2d.cc | 15 ++++++++++++++-
 src/context2d.h  |  1 +
 3 files changed, 20 insertions(+), 1 deletion(-)

diff --git a/lib/canvas.js b/lib/canvas.js
index 0bb9c1a..91c1d05 100644
--- a/lib/canvas.js
+++ b/lib/canvas.js
@@ -146,6 +146,11 @@ Context2d.prototype.createRadialGradient = function(x0, y0, r0, x1, y1, r1){
   return new CanvasGradient(x0, y0, r0, x1, y1, r1);
 };
 
+Context2d.prototype.setTransform = function(){
+  this.resetTransform();
+  return this.transform.apply(this, arguments);
+};
+
 /**
  * Set the fill style with the given css color string.
  *
diff --git a/src/context2d.cc b/src/context2d.cc
index 37d5b9e..9bafb90 100644
--- a/src/context2d.cc
+++ b/src/context2d.cc
@@ -78,6 +78,7 @@ Context2d::Initialize(Handle<Object> target) {
   NODE_SET_PROTOTYPE_METHOD(t, "rotate", Rotate);
   NODE_SET_PROTOTYPE_METHOD(t, "translate", Translate);
   NODE_SET_PROTOTYPE_METHOD(t, "transform", Transform);
+  NODE_SET_PROTOTYPE_METHOD(t, "resetTransform", ResetTransform);
   NODE_SET_PROTOTYPE_METHOD(t, "scale", Scale);
   NODE_SET_PROTOTYPE_METHOD(t, "fill", Fill);
   NODE_SET_PROTOTYPE_METHOD(t, "stroke", Stroke);
@@ -485,7 +486,7 @@ Context2d::Rotate(const Arguments &args) {
 }
 
 /*
- * Transform.
+ * Modify the CTM.
  */
 
 Handle<Value>
@@ -507,6 +508,18 @@ Context2d::Transform(const Arguments &args) {
   return Undefined();
 }
 
+/*
+ * Reset the CTM, used internally by setTransform().
+ */
+
+Handle<Value>
+Context2d::ResetTransform(const Arguments &args) {
+  HandleScope scope;
+  Context2d *context = ObjectWrap::Unwrap<Context2d>(args.This());
+  cairo_identity_matrix(context->getContext());
+  return Undefined();
+}
+
 /*
  * Translate transformation.
  */
diff --git a/src/context2d.h b/src/context2d.h
index b348c9f..a242152 100644
--- a/src/context2d.h
+++ b/src/context2d.h
@@ -30,6 +30,7 @@ class Context2d: public node::ObjectWrap {
     static Handle<Value> Translate(const Arguments &args);
     static Handle<Value> Scale(const Arguments &args);
     static Handle<Value> Transform(const Arguments &args);
+    static Handle<Value> ResetTransform(const Arguments &args);
     static Handle<Value> BeginPath(const Arguments &args);
     static Handle<Value> ClosePath(const Arguments &args);
     static Handle<Value> Fill(const Arguments &args);