cc: ImageDecodes: Move ImageHijackCanvas to a separate file.

cc/playback/image_hijack_canvas.cc

+// Copyright 2016 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/playback/image_hijack_canvas.h"
+
+#include "cc/playback/discardable_image_map.h"
+#include "cc/tiles/image_decode_controller.h"
+#include "third_party/skia/include/core/SkTLazy.h"
+
+namespace cc {
+namespace {
+
+SkIRect RoundOutRect(const SkRect& rect) {
+  SkIRect result;
+  rect.roundOut(&result);
+  return result;
+}
+
+class ScopedDecodedImageLock {
+ public:
+  ScopedDecodedImageLock(ImageDecodeController* image_decode_controller,
+                         const SkImage* image,
+                         const SkRect& src_rect,
+                         const SkSize& scale,
+                         bool is_decomposable,
+                         bool has_perspective,
+                         const SkPaint* paint)
+      : image_decode_controller_(image_decode_controller),
+        draw_image_(image,
+                    RoundOutRect(src_rect),
+                    scale,
+                    paint ? paint->getFilterQuality() : kNone_SkFilterQuality,
+                    has_perspective,
+                    is_decomposable),
+        decoded_draw_image_(
+            image_decode_controller_->GetDecodedImageForDraw(draw_image_)) {
+    DCHECK(image->isLazyGenerated());
+    if (paint)
+      decoded_paint_.set(*paint)->setFilterQuality(
+          decoded_draw_image_.filter_quality());
+  }
+
+  ~ScopedDecodedImageLock() {
+    image_decode_controller_->DrawWithImageFinished(draw_image_,
+                                                    decoded_draw_image_);
+  }
+
+  const DecodedDrawImage& decoded_image() const { return decoded_draw_image_; }
+  const SkPaint* decoded_paint() const { return decoded_paint_.getMaybeNull(); }
+
+ private:
+  ImageDecodeController* image_decode_controller_;
+  DrawImage draw_image_;
+  DecodedDrawImage decoded_draw_image_;
+  // TODO(fmalita): use base::Optional when it becomes available
+  SkTLazy<SkPaint> decoded_paint_;
+};
+
+}  // namespace
+
+ImageHijackCanvas::ImageHijackCanvas(
+    int width,
+    int height,
+    ImageDecodeController* image_decode_controller)
+    : SkNWayCanvas(width, height),
+      image_decode_controller_(image_decode_controller) {}
+
+void ImageHijackCanvas::onDrawPicture(const SkPicture* picture,
+                                      const SkMatrix* matrix,
+                                      const SkPaint* paint) {
+  // Ensure that pictures are unpacked by this canvas, instead of being
+  // forwarded to the raster canvas.
+  SkCanvas::onDrawPicture(picture, matrix, paint);
+}
+
+void ImageHijackCanvas::onDrawImage(const SkImage* image,
+                                    SkScalar x,
+                                    SkScalar y,
+                                    const SkPaint* paint) {
+  if (!image->isLazyGenerated()) {
+    SkNWayCanvas::onDrawImage(image, x, y, paint);
+    return;
+  }
+
+  SkMatrix ctm = getTotalMatrix();
+
+  SkSize scale;
+  bool is_decomposable = ExtractScale(ctm, &scale);
+  ScopedDecodedImageLock scoped_lock(
+      image_decode_controller_, image,
+      SkRect::MakeIWH(image->width(), image->height()), scale, is_decomposable,
+      ctm.hasPerspective(), paint);
+  const DecodedDrawImage& decoded_image = scoped_lock.decoded_image();
+  if (!decoded_image.image())
+    return;
+
+  DCHECK_EQ(0, static_cast<int>(decoded_image.src_rect_offset().width()));
+  DCHECK_EQ(0, static_cast<int>(decoded_image.src_rect_offset().height()));
+  const SkPaint* decoded_paint = scoped_lock.decoded_paint();
+
+  bool need_scale = !decoded_image.is_scale_adjustment_identity();
+  if (need_scale) {
+    SkNWayCanvas::save();
+    SkNWayCanvas::scale(1.f / (decoded_image.scale_adjustment().width()),
+                        1.f / (decoded_image.scale_adjustment().height()));
+  }
+  SkNWayCanvas::onDrawImage(decoded_image.image(), x, y, decoded_paint);
+  if (need_scale)
+    SkNWayCanvas::restore();
+}
+
+void ImageHijackCanvas::onDrawImageRect(const SkImage* image,
+                                        const SkRect* src,
+                                        const SkRect& dst,
+                                        const SkPaint* paint,
+                                        SrcRectConstraint constraint) {
+  if (!image->isLazyGenerated()) {
+    SkNWayCanvas::onDrawImageRect(image, src, dst, paint, constraint);
+    return;
+  }
+
+  SkRect src_storage;
+  if (!src) {
+    src_storage = SkRect::MakeIWH(image->width(), image->height());
+    src = &src_storage;
+  }
+  SkMatrix matrix;
+  matrix.setRectToRect(*src, dst, SkMatrix::kFill_ScaleToFit);
+  matrix.postConcat(getTotalMatrix());
+
+  SkSize scale;
+  bool is_decomposable = ExtractScale(matrix, &scale);
+  ScopedDecodedImageLock scoped_lock(image_decode_controller_, image, *src,
+                                     scale, is_decomposable,
+                                     matrix.hasPerspective(), paint);
+  const DecodedDrawImage& decoded_image = scoped_lock.decoded_image();
+  if (!decoded_image.image())
+    return;
+
+  const SkPaint* decoded_paint = scoped_lock.decoded_paint();
+
+  SkRect adjusted_src =
+      src->makeOffset(decoded_image.src_rect_offset().width(),
+                      decoded_image.src_rect_offset().height());
+  if (!decoded_image.is_scale_adjustment_identity()) {
+    float x_scale = decoded_image.scale_adjustment().width();
+    float y_scale = decoded_image.scale_adjustment().height();
+    adjusted_src = SkRect::MakeXYWH(
+        adjusted_src.x() * x_scale, adjusted_src.y() * y_scale,
+        adjusted_src.width() * x_scale, adjusted_src.height() * y_scale);
+  }
+  SkNWayCanvas::onDrawImageRect(decoded_image.image(), &adjusted_src, dst,
+                                decoded_paint, constraint);
+}
+
+void ImageHijackCanvas::onDrawImageNine(const SkImage* image,
+                                        const SkIRect& center,
+                                        const SkRect& dst,
+                                        const SkPaint* paint) {
+  // No cc embedder issues image nine calls.
+  NOTREACHED();
+}
+
+}  // namespace cc