gpu: play skp files through the command buffer

gpu/skia_runner/sk_picture_rasterizer.cc

+// Copyright (c) 2015 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 "gpu/skia_runner/sk_picture_rasterizer.h"
+
+#include <iostream>
+
+#include "third_party/skia/include/core/SkCanvas.h"
+#include "third_party/skia/include/core/SkSurface.h"
+#include "third_party/skia/include/core/SkSurfaceProps.h"
+
+namespace skia_runner {
+
+SkPictureRasterizer::SkPictureRasterizer(skia::RefPtr<GrContext> gr_context,
+                                         int max_texture_size)
+    : use_lcd_text_(false),
+      use_distance_field_text_(false),
+      msaa_sample_count_(0),
+      max_texture_size_(max_texture_size),
+      gr_context_(gr_context) {
+}
+
+SkPictureRasterizer::~SkPictureRasterizer() {
+}
+
+SkBitmap SkPictureRasterizer::RasterizeTile(const SkPicture* picture,
+                                            const SkRect& rect) const {
+  DCHECK(gr_context_);
+
+  GrSurfaceDesc desc;
+  desc.fFlags = kRenderTarget_GrSurfaceFlag;
+  desc.fWidth = rect.width();
+  desc.fHeight = rect.height();
+  desc.fConfig = kBGRA_8888_GrPixelConfig;
+  desc.fOrigin = kTopLeft_GrSurfaceOrigin;
+  desc.fSampleCnt = msaa_sample_count_;
+  DCHECK(desc.fSampleCnt == 0 || desc.fSampleCnt == 2 || desc.fSampleCnt == 4 ||
+         desc.fSampleCnt == 8 || desc.fSampleCnt == 16);
+
+  skia::RefPtr<GrTexture> gr_texture(skia::AdoptRef(
+      gr_context_->textureProvider()->createTexture(desc, false, nullptr, 0)));
+
+  if (gr_texture) {
+    uint32_t flags = use_distance_field_text_
+                         ? SkSurfaceProps::kUseDistanceFieldFonts_Flag
+                         : 0;
+    SkSurfaceProps surface_props =
+        use_lcd_text_
+            ? SkSurfaceProps(flags, SkSurfaceProps::kLegacyFontHost_InitType)
+            : SkSurfaceProps(flags, kUnknown_SkPixelGeometry);
+
+    skia::RefPtr<SkSurface> sk_surface(
+        skia::AdoptRef(SkSurface::NewRenderTargetDirect(
+            gr_texture->asRenderTarget(), &surface_props)));
+    SkCanvas* canvas = sk_surface->getCanvas();
+    canvas->translate(-rect.left(), -rect.top());
+    canvas->drawPicture(picture);
+
+    SkBitmap bitmap;
+    bitmap.setInfo(canvas->imageInfo());
+    if (canvas->readPixels(&bitmap, 0, 0)) {
+      return bitmap;
+    }
+  }
+  return SkBitmap();
+}
+
+SkBitmap SkPictureRasterizer::Rasterize(const SkPicture* picture) const {
+  if (!gr_context_)
+    return SkBitmap();
+
+  SkRect picture_rect = picture->cullRect();
+  if (picture_rect.width() <= max_texture_size_ &&
+      picture_rect.height() <= max_texture_size_)
+    return RasterizeTile(picture, picture_rect);
+
+  // If the picture doesn't fit within a single texture, we need to generate
+  // tiles and assemble into a final bitmap.
+  SkBitmap bitmap;
+  bitmap.allocN32Pixels(picture_rect.width(), picture_rect.height());
+  SkCanvas canvas(bitmap);
+  int num_tiles_x = picture_rect.width() / max_texture_size_ + 1;
+  int num_tiles_y = picture_rect.height() / max_texture_size_ + 1;
+  for (int y = 0; y < num_tiles_y; ++y) {
+    SkRect tile_rect;
+    tile_rect.fTop = picture_rect.top() + y * max_texture_size_;
+    tile_rect.fBottom =
+        std::min(tile_rect.fTop + max_texture_size_, picture_rect.bottom());
+    for (int x = 0; x < num_tiles_x; ++x) {
+      tile_rect.fLeft = picture_rect.left() + x * max_texture_size_;
+      tile_rect.fRight =
+          std::min(tile_rect.fLeft + max_texture_size_, picture_rect.right());
+      SkBitmap tile = RasterizeTile(picture, tile_rect);
+      canvas.drawBitmap(tile, tile_rect.left(), tile_rect.top());
+    }
+  }
+  return bitmap;
+}
+
+}  // namepsace skia_runner