Bug 933030 - Eliminate thebes use from CanvasRenderingContext2D.cpp r=mattwoodrow

content/canvas/src/CanvasRenderingContext2D.cpp

@@ -75,6 +75,7 @@
 #include "mozilla/dom/TypedArray.h"
 #include "mozilla/gfx/2D.h"
 #include "mozilla/gfx/PathHelpers.h"
+#include "mozilla/gfx/DataSurfaceHelpers.h"
 #include "mozilla/ipc/DocumentRendererParent.h"
 #include "mozilla/ipc/PDocumentRendererParent.h"
 #include "mozilla/MathAlgorithms.h"
@@ -1060,40 +1061,20 @@ CanvasRenderingContext2D::GetImageBuffer(uint8_t** aImageBuffer,
   *aImageBuffer = nullptr;
   *aFormat = 0;
 
-  nsRefPtr<gfxASurface> surface;
-  nsresult rv = GetThebesSurface(getter_AddRefs(surface));
-  if (NS_FAILED(rv)) {
+  EnsureTarget();
+  RefPtr<SourceSurface> snapshot = mTarget->Snapshot();
+  if (!snapshot) {
     return;
   }
 
-  static const fallible_t fallible = fallible_t();
-  uint8_t* imageBuffer = new (fallible) uint8_t[mWidth * mHeight * 4];
-  if (!imageBuffer) {
+  RefPtr<DataSourceSurface> data = snapshot->GetDataSurface();
+  if (!data) {
     return;
   }
 
-  nsRefPtr<gfxImageSurface> imgsurf =
-    new gfxImageSurface(imageBuffer,
-                        gfxIntSize(mWidth, mHeight),
-                        mWidth * 4,
-                        gfxImageFormatARGB32);
+  MOZ_ASSERT(data->GetSize() == IntSize(mWidth, mHeight));
 
-  if (!imgsurf || imgsurf->CairoStatus()) {
-    delete[] imageBuffer;
-    return;
-  }
-
-  nsRefPtr<gfxContext> ctx = new gfxContext(imgsurf);
-  if (!ctx || ctx->HasError()) {
-    delete[] imageBuffer;
-    return;
-  }
-
-  ctx->SetOperator(gfxContext::OPERATOR_SOURCE);
-  ctx->SetSource(surface, gfxPoint(0, 0));
-  ctx->Paint();
-
-  *aImageBuffer = imageBuffer;
+  *aImageBuffer = SurfaceToPackedBGRA(data);
   *aFormat = imgIEncoder::INPUT_FORMAT_HOSTARGB;
 }
 

gfx/2d/DataSurfaceHelpers.h

@@ -0,0 +1,81 @@
+/* -*- Mode: C++; tab-width: 20; indent-tabs-mode: nil; c-basic-offset: 2 -*-
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#pragma once
+
+#include "2D.h"
+#include "mozilla/mozalloc.h"
+
+namespace mozilla {
+namespace gfx {
+
+static inline void
+ConvertBGRXToBGRA(uint8_t* aData, const IntSize &aSize, int32_t aStride)
+{
+  uint32_t* pixel = reinterpret_cast<uint32_t*>(aData);
+
+  for (int row = 0; row < aSize.height; ++row) {
+    for (int column = 0; column < aSize.width; ++column) {
+#ifdef IS_BIG_ENDIAN
+      pixel[column] |= 0x000000FF;
+#else
+      pixel[column] |= 0xFF000000;
+#endif
+    }
+    pixel += (aStride/4);
+  }
+}
+
+/*
+ * Convert aSurface to a packed buffer in BGRA format. The pixel data is
+ * returned in a buffer allocated with new uint8_t[].
+ */
+inline uint8_t *
+SurfaceToPackedBGRA(SourceSurface *aSurface)
+{
+  RefPtr<DataSourceSurface> data = aSurface->GetDataSurface();
+  if (!data) {
+    return nullptr;
+  }
+
+  SurfaceFormat format = data->GetFormat();
+  if (format != FORMAT_B8G8R8A8 && format != FORMAT_B8G8R8X8) {
+    return nullptr;
+  }
+
+  IntSize size = data->GetSize();
+  static const fallible_t fallible = fallible_t();
+  uint8_t* imageBuffer = new (fallible) uint8_t[size.width * size.height * sizeof(uint32_t)];
+  if (!imageBuffer) {
+    return nullptr;
+  }
+
+  size_t stride = data->Stride();
+
+  uint32_t* src = reinterpret_cast<uint32_t*>(data->GetData());
+  uint32_t* dst = reinterpret_cast<uint32_t*>(imageBuffer);
+
+  if (stride == size.width * sizeof(uint32_t)) {
+    // DataSourceSurface is already packed. We can use memcpy.
+    memcpy(dst, src, size.width * size.height * sizeof(uint32_t));
+  } else {
+    for (int row = 0; row < size.height; ++row) {
+      for (int column = 0; column < size.width; ++column) {
+        *dst++ = src[column];
+      }
+      src += (stride/4);
+    }
+  }
+
+  if (format == FORMAT_B8G8R8X8) {
+    // Convert BGRX to BGRA by setting a to 255.
+    ConvertBGRXToBGRA(reinterpret_cast<uint8_t *>(imageBuffer), size, size.width * sizeof(uint32_t));
+  }
+
+  return imageBuffer;
+}
+
+}
+}

gfx/2d/DrawTargetSkia.cpp

@@ -25,6 +25,7 @@
 #include "Logging.h"
 #include "HelpersSkia.h"
 #include "Tools.h"
+#include "DataSurfaceHelpers.h"
 #include <algorithm>
 
 namespace mozilla {

gfx/2d/HelpersSkia.h

@@ -154,19 +154,6 @@ StrokeOptionsToPaint(SkPaint& aPaint, const StrokeOptions &aOptions)
   return true;
 }
 
-static inline void
-ConvertBGRXToBGRA(unsigned char* aData, const IntSize &aSize, int32_t aStride)
-{
-    uint32_t* pixel = reinterpret_cast<uint32_t*>(aData);
-
-    for (int row = 0; row < aSize.height; ++row) {
-        for (int column = 0; column < aSize.width; ++column) {
-            pixel[column] |= 0xFF000000;
-        }
-        pixel += (aStride/4);
-    }
-}
-
 static inline SkXfermode::Mode
 GfxOpToSkiaOp(CompositionOp op)
 {

gfx/2d/SourceSurfaceSkia.cpp

@@ -10,6 +10,7 @@
 #include "skia/SkDevice.h"
 #include "HelpersSkia.h"
 #include "DrawTargetSkia.h"
+#include "DataSurfaceHelpers.h"
 
 namespace mozilla {
 namespace gfx {

gfx/2d/moz.build

@@ -20,6 +20,7 @@ EXPORTS.mozilla.gfx += [
     'BaseSize.h',
     'Blur.h',
     'BorrowedContext.h',
+    'DataSurfaceHelpers.h',
     'Matrix.h',
     'PathHelpers.h',
     'Point.h',