Raster PictureLayerTiling with fractional translation

cc/raster/raster_buffer_provider.cc

 // Copyright 2013 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 "cc/raster/raster_buffer_provider.h"
 
 #include <stddef.h>
 
 #include "base/trace_event/trace_event.h"
 #include "cc/playback/raster_source.h"
@@ skipping 34 matching lines @@
 // static
 void RasterBufferProvider::PlaybackToMemory(
     void* memory,
     ResourceFormat format,
     const gfx::Size& size,
     size_t stride,
     const RasterSource* raster_source,
     const gfx::Rect& canvas_bitmap_rect,
     const gfx::Rect& canvas_playback_rect,
     float scale,
+    const gfx::Vector2dF& translation,
     const RasterSource::PlaybackSettings& playback_settings) {
   TRACE_EVENT0("disabled-by-default-cc.debug",
                "RasterBufferProvider::PlaybackToMemory");
 
   DCHECK(IsSupportedPlaybackToMemoryFormat(format)) << format;
 
   // Uses kPremul_SkAlphaType since the result is not known to be opaque.
   SkImageInfo info =
       SkImageInfo::MakeN32(size.width(), size.height(), kPremul_SkAlphaType);
 
   // Use unknown pixel geometry to disable LCD text.
   SkSurfaceProps surface_props(0, kUnknown_SkPixelGeometry);
   if (raster_source->CanUseLCDText()) {
     // LegacyFontHost will get LCD text and skia figures out what type to use.
     surface_props = SkSurfaceProps(SkSurfaceProps::kLegacyFontHost_InitType);
   }
 
   if (!stride)
     stride = info.minRowBytes();
   DCHECK_GT(stride, 0u);
 
   switch (format) {
     case RGBA_8888:
     case BGRA_8888: {
       sk_sp<SkSurface> surface =
           SkSurface::MakeRasterDirect(info, memory, stride, &surface_props);
-      raster_source->PlaybackToCanvas(surface->getCanvas(), canvas_bitmap_rect,
-                                      canvas_playback_rect, scale,
-                                      playback_settings);
+      SkCanvas* canvas = surface->getCanvas();
+      canvas->translate(-canvas_bitmap_rect.x(), -canvas_bitmap_rect.y());
+      canvas->clipRect(gfx::RectToSkRect(canvas_playback_rect));
+      canvas->translate(translation.x(), translation.y());
+      canvas->scale(scale, scale);
+      raster_source->PlaybackToCanvas(surface->getCanvas(), playback_settings);
       return;
     }
     case RGBA_4444:
     case ETC1: {
       sk_sp<SkSurface> surface = SkSurface::MakeRaster(info, &surface_props);
+      SkCanvas* canvas = surface->getCanvas();
+      canvas->translate(-canvas_bitmap_rect.x(), -canvas_bitmap_rect.y());
       // TODO(reveman): Improve partial raster support by reducing the size of
-      // playback rect passed to PlaybackToCanvas. crbug.com/519070
-      raster_source->PlaybackToCanvas(surface->getCanvas(), canvas_bitmap_rect,
-                                      canvas_bitmap_rect, scale,
-                                      playback_settings);
+      // the clip rect here. crbug.com/519070
+      canvas->clipRect(gfx::RectToSkRect(canvas_bitmap_rect));
+      canvas->translate(translation.x(), translation.y());
+      canvas->scale(scale, scale);
+      raster_source->PlaybackToCanvas(surface->getCanvas(), playback_settings);
 
       if (format == ETC1) {
         TRACE_EVENT0("cc",
                      "RasterBufferProvider::PlaybackToMemory::CompressETC1");
         DCHECK_EQ(size.width() % 4, 0);
         DCHECK_EQ(size.height() % 4, 0);
         std::unique_ptr<TextureCompressor> texture_compressor =
             TextureCompressor::Create(TextureCompressor::kFormatETC1);
         SkPixmap pixmap;
         surface->peekPixels(&pixmap);
@@ skipping 38 matching lines @@
     case RGB_565:
     case RED_8:
     case LUMINANCE_F16:
       return false;
   }
   NOTREACHED();
   return false;
 }
 
 }  // namespace cc