Refactor blits

base/gfx/blit.cc

+// Copyright (c) 2009 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "base/gfx/blit.h"
+
+#if defined(OS_LINUX)
+#include <cairo/cairo.h>
+#endif
+
+#include "base/gfx/point.h"
+#include "base/gfx/rect.h"
+#if defined(OS_MACOSX)
+#include "base/scoped_cftyperef.h"
+#endif
+#include "skia/ext/platform_canvas.h"
+#include "skia/ext/platform_device.h"
+
+namespace gfx {
+
+void BlitContextToContext(NativeDrawingContext dst_context,
+                          const Rect& dst_rect,
+                          NativeDrawingContext src_context,
+                          const Point& src_origin) {
+#if defined(OS_WIN)
+  BitBlt(dst_context, dst_rect.x(), dst_rect.y(),
+         dst_rect.width(), dst_rect.height(),
+         src_context, src_origin.x(), src_origin.y(), SRCCOPY);
+#elif defined(OS_MACOSX)
+  Rect src_rect(src_origin, dst_rect.size());
+  scoped_cftyperef<CGImageRef>
+      src_image(CGBitmapContextCreateImage(src_context));
+  scoped_cftyperef<CGImageRef> src_sub_image(
+      CGImageCreateWithImageInRect(src_image, src_rect.ToCGRect()));
+  CGContextDrawImage(dst_context, dst_rect.ToCGRect(), src_sub_image);
+#elif defined(OS_LINUX)
+  cairo_save(dst_context);
+  double surface_x = src_origin.x();
+  double surface_y = src_origin.y();
+  cairo_user_to_device(src_context, &surface_x, &surface_y);
+  cairo_set_source_surface(dst_context, cairo_get_target(src_context),
+                           dst_rect.x()-surface_x, dst_rect.y()-surface_y);
+  cairo_rectangle(dst_context, dst_rect.x(), dst_rect.y(),
+                  dst_rect.width(), dst_rect.height());
+  cairo_clip(dst_context);
+  cairo_paint(dst_context);
+  cairo_restore(dst_context);
+#endif
+}
+
+static NativeDrawingContext GetContextFromCanvas(
+    skia::PlatformCanvas *canvas) {
+  skia::PlatformDevice& device = canvas->getTopPlatformDevice();
+#if defined(OS_WIN)
+  return device.getBitmapDC();
+#elif defined(OS_MACOSX)
+  return device.GetBitmapContext();
+#elif defined(OS_LINUX)
+  return device.beginPlatformPaint();
+#endif
+}
+
+void BlitContextToCanvas(skia::PlatformCanvas *dst_canvas,
+                         const Rect& dst_rect,
+                         NativeDrawingContext src_context,
+                         const Point& src_origin) {
+  BlitContextToContext(GetContextFromCanvas(dst_canvas), dst_rect,
+                       src_context, src_origin);
+}
+
+void BlitCanvasToContext(NativeDrawingContext dst_context,
+                         const Rect& dst_rect,
+                         skia::PlatformCanvas *src_canvas,
+                         const Point& src_origin) {
+  BlitContextToContext(dst_context, dst_rect,
+                       GetContextFromCanvas(src_canvas), src_origin);
+}
+
+void BlitCanvasToCanvas(skia::PlatformCanvas *dst_canvas,
+                        const Rect& dst_rect,
+                        skia::PlatformCanvas *src_canvas,
+                        const Point& src_origin) {
+  BlitContextToContext(GetContextFromCanvas(dst_canvas), dst_rect,
+                       GetContextFromCanvas(src_canvas), src_origin);
+}
+
+}  // namespace gfx