Merge branch 'putImageData'

src/CanvasRenderingContext2d.cc

@@ -10,6 +10,7 @@
 #include <stdlib.h>
 #include "Canvas.h"
 #include "Image.h"
+#include "ImageData.h"
 #include "CanvasRenderingContext2d.h"
 #include "CanvasGradient.h"
 
@@ -65,6 +66,7 @@ Context2d::Initialize(Handle<Object> target) {
   // Prototype
   Local<ObjectTemplate> proto = t->PrototypeTemplate();
   NODE_SET_PROTOTYPE_METHOD(t, "drawImage", DrawImage);
+  NODE_SET_PROTOTYPE_METHOD(t, "putImageData", PutImageData);
   NODE_SET_PROTOTYPE_METHOD(t, "save", Save);
   NODE_SET_PROTOTYPE_METHOD(t, "restore", Restore);
   NODE_SET_PROTOTYPE_METHOD(t, "rotate", Rotate);
@@ -381,6 +383,92 @@ Context2d::New(const Arguments &args) {
   return args.This();
 }
 
+/*
+ * Put image data.
+ *
+ *  - imageData, dx, dy
+ *  - imageData, dx, dy, sx, sy, dw, dh
+ *
+ */
+
+Handle<Value>
+Context2d::PutImageData(const Arguments &args) {
+  HandleScope scope;
+  // TODO: validate
+  Context2d *context = ObjectWrap::Unwrap<Context2d>(args.This());
+  ImageData *imageData = ObjectWrap::Unwrap<ImageData>(args[0]->ToObject());
+  PixelArray *arr = imageData->pixelArray();
+  
+  uint8_t *src = arr->data();
+  uint8_t *dst = context->canvas()->data();
+
+  int srcStride = arr->stride()
+    , dstStride = context->canvas()->stride();
+
+  int sx = 0
+    , sy = 0
+    , sw = 0
+    , sh = 0
+    , dx = args[1]->NumberValue()
+    , dy = args[2]->NumberValue()
+    , rows
+    , cols;
+
+  // TODO: spec boundaries
+  switch (args.Length()) {
+    // imageData, dx, dy
+    case 3:
+      cols = arr->width();
+      rows = arr->height();
+      break;
+    // imageData, dx, dy, sx, sy, dw, dh
+    case 7: {
+      sx = args[3]->NumberValue();
+      sy = args[4]->NumberValue();
+      sw = args[5]->NumberValue();
+      sh = args[6]->NumberValue();
+      cols = sw;
+      rows = sh;
+      dx += sx; 
+      dy += sy; 
+      }
+      break;
+    default:
+      return ThrowException(Exception::Error(String::New("invalid arguments")));
+  }
+
+  uint8_t *srcRows = src + sy * srcStride + sx * 4;
+  for (int y = 0; y < rows; ++y) {
+    uint32_t *row = (uint32_t *)(dst + dstStride * (y + dy));
+    for (int x = 0; x < cols; ++x) {
+      int bx = x * 4;
+      uint32_t *pixel = row + x + dx;
+
+      // RGBA
+      uint8_t a = srcRows[bx + 3];
+      uint8_t r = srcRows[bx + 0];
+      uint8_t g = srcRows[bx + 1];
+      uint8_t b = srcRows[bx + 2];
+
+      // ARGB
+      *pixel = a << 24
+        | r << 16
+        | g << 8
+        | b;
+    }
+    srcRows += srcStride;
+  }
+
+  cairo_surface_mark_dirty_rectangle(
+      context->canvas()->surface()
+    , dx
+    , dy
+    , cols
+    , rows);
+
+  return Undefined();
+}
+
 /*
  * Draw image src image to the destination (context).
  *

src/CanvasRenderingContext2d.h

@@ -48,6 +48,7 @@ class Context2d: public node::ObjectWrap {
     static void Initialize(Handle<Object> target);
     static Handle<Value> New(const Arguments &args);
     static Handle<Value> DrawImage(const Arguments &args);
+    static Handle<Value> PutImageData(const Arguments &args);
     static Handle<Value> Save(const Arguments &args);
     static Handle<Value> Restore(const Arguments &args);
     static Handle<Value> Rotate(const Arguments &args);

src/PixelArray.cc

@@ -85,23 +85,36 @@ PixelArray::PixelArray(Canvas *canvas, int sx, int sy, int width, int height):
   // Alloc space for our new data
   uint8_t *dst = alloc();
   uint8_t *src = canvas->data();
-  int s = stride();
+  int srcStride = canvas->stride()
+    , dstStride = stride();
 
   // Normalize data (argb -> rgba)
   for (int y = 0; y < height; ++y) {
-    uint32_t *row = (uint32_t *)(src + s * y);
+    uint32_t *row = (uint32_t *)(src + srcStride * (y + sy));
     for (int x = 0; x < width; ++x) {
       int bx = x * 4;
-      uint32_t *pixel = row + x;
+      uint32_t *pixel = row + x + sx;
 
-      // premultiplied
+      // ARGB
       uint8_t a = *pixel >> 24;
+      uint8_t r = *pixel >> 16;
+      uint8_t g = *pixel >> 8;
+      uint8_t b = *pixel;
+
+      // undo premultiplication
       dst[bx + 3] = a;
-      dst[bx + 0] = (*pixel >> 16) * 255 / a;
-      dst[bx + 1] = (*pixel >> 8) * 255 / a;
-      dst[bx + 2] = *pixel * 255 / a;
+      // TODO: abstract
+      if (a) {
+        dst[bx + 0] = r * 255 / a;
+        dst[bx + 1] = g * 255 / a;
+        dst[bx + 2] = b * 255 / a;
+      } else {
+        dst[bx + 0] = r;
+        dst[bx + 1] = g;
+        dst[bx + 2] = b;
+      }
     }
-    dst += s;
+    dst += dstStride;
   }
 }
 

test/public/tests.js

@@ -1440,4 +1440,79 @@ tests['drawImage(img,sx,sy,sw,sh,x,y,w,h)'] = function(ctx, done){
     done();
   };
   img.src = 'state.png';
+};
+
+tests['putImageData()'] = function(ctx){
+  for (i=0;i<6;i++){
+    for (j=0;j<6;j++){
+      ctx.fillStyle = 'rgb(' + Math.floor(255-42.5*i) + ',' + 
+                       Math.floor(255-42.5*j) + ',0)';
+      ctx.fillRect(j*25,i*25,25,25);
+    }
+  }
+  var data = ctx.getImageData(0,0,50,50);
+  ctx.putImageData(data,10,10);
+};
+
+tests['putImageData() 2'] = function(ctx){
+  for (i=0;i<6;i++){
+    for (j=0;j<6;j++){
+      ctx.fillStyle = 'rgb(' + Math.floor(255-42.5*i) + ',' + 
+                       Math.floor(255-42.5*j) + ',0)';
+      ctx.fillRect(j*25,i*25,25,25);
+    }
+  }
+  var data = ctx.getImageData(25,25,50,50);
+  ctx.putImageData(data,10,10);
+};
+
+tests['putImageData() 3'] = function(ctx){
+  for (i=0;i<6;i++){
+    for (j=0;j<6;j++){
+      ctx.fillStyle = 'rgb(' + Math.floor(255-42.5*i) + ',' + 
+                       Math.floor(255-42.5*j) + ',0)';
+      ctx.fillRect(j*25,i*25,25,25);
+    }
+  }
+  var data = ctx.getImageData(10,25,10,50);
+  ctx.putImageData(data,50,10);
+};
+
+tests['putImageData() 4'] = function(ctx){
+  for (i=0;i<6;i++){
+    for (j=0;j<6;j++){
+      ctx.fillStyle = 'rgb(' + Math.floor(255-42.5*i) + ',' + 
+                       Math.floor(255-42.5*j) + ',0)';
+      ctx.fillRect(j*25,i*25,25,25);
+    }
+  }
+  ctx.strokeRect(30,30,30,30);
+  var data = ctx.getImageData(0,0,50,50);
+  ctx.putImageData(data,30,30,10,10,30,30);
+};
+
+tests['putImageData() 5'] = function(ctx){
+  for (i=0;i<6;i++){
+    for (j=0;j<6;j++){
+      ctx.fillStyle = 'rgb(' + Math.floor(255-42.5*i) + ',' + 
+                       Math.floor(255-42.5*j) + ',0)';
+      ctx.fillRect(j*25,i*25,25,25);
+    }
+  }
+  ctx.strokeRect(60,60,50,30);
+  var data = ctx.getImageData(0,0,50,50);
+  ctx.putImageData(data,60,60,0,0,50,30);
+};
+
+tests['putImageData() 6'] = function(ctx){
+  for (i=0;i<6;i++){
+    for (j=0;j<6;j++){
+      ctx.fillStyle = 'rgb(' + Math.floor(255-42.5*i) + ',' + 
+                       Math.floor(255-42.5*j) + ',0)';
+      ctx.fillRect(j*25,i*25,25,25);
+    }
+  }
+  ctx.strokeRect(60,60,50,30);
+  var data = ctx.getImageData(0,0,50,50);
+  ctx.putImageData(data,60,60,10,0,35,30);
 };