UI Resource Manager

cc/layers/picture_scrollbar_layer.cc

Index: cc/layers/picture_scrollbar_layer.cc
===================================================================
--- cc/layers/picture_scrollbar_layer.cc	(revision 0)
+++ cc/layers/picture_scrollbar_layer.cc	(revision 0)
@@ -0,0 +1,307 @@
+// Copyright 2012 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/layers/picture_scrollbar_layer.h"
+
+#if !USE_REGULAR_SCROLLBAR
+
+#include "base/auto_reset.h"
+#include "base/basictypes.h"
+#include "base/debug/trace_event.h"
+#include "cc/layers/picture_scrollbar_layer_impl.h"
+#include "cc/resources/caching_bitmap_content_layer_updater.h"
+#include "cc/resources/layer_painter.h"
+#include "cc/resources/resource_update_queue.h"
+#include "cc/resources/ui_resource_manager.h"
+#include "cc/trees/layer_tree_host.h"
+#include "cc/trees/layer_tree_impl.h"
+#include "skia/ext/platform_canvas.h"
+#include "skia/ext/refptr.h"
+#include "third_party/skia/include/core/SkSize.h"
+#include "ui/gfx/rect_conversions.h"
+
+namespace cc {
+
+scoped_ptr<LayerImpl> ScrollbarLayer::CreateLayerImpl(
+    LayerTreeImpl* tree_impl) {
+  return ScrollbarLayerImpl::Create(
+      tree_impl, id(), scrollbar_->Orientation()).PassAs<LayerImpl>();
+}
+
+scoped_refptr<ScrollbarLayer> ScrollbarLayer::Create(
+    scoped_ptr<Scrollbar> scrollbar,
+    int scroll_layer_id) {
+  return make_scoped_refptr(new ScrollbarLayer(scrollbar.Pass(),
+                                               scroll_layer_id));
+}
+
+ScrollbarLayer::ScrollbarLayer(
+    scoped_ptr<Scrollbar> scrollbar,
+    int scroll_layer_id)
+    : scrollbar_(scrollbar.Pass()),
+      scroll_layer_id_(scroll_layer_id),
+      track_ui_resource_id_(0),
+      thumb_ui_resource_id_(0),
+      track_ui_resource_status_(UIResourceManagerClient::NOT_READY),
+      thumb_ui_resource_status_(UIResourceManagerClient::NOT_READY),
+      skip_update_(false) {
+  if (!scrollbar_->IsOverlay())
+    SetShouldScrollOnMainThread(true);
+}
+
+ScrollbarLayer::~ScrollbarLayer() {}
+
+void ScrollbarLayer::SetScrollLayerId(int id) {
+  if (id == scroll_layer_id_)
+    return;
+
+  scroll_layer_id_ = id;
+  SetNeedsFullTreeSync();
+}
+
+bool ScrollbarLayer::OpacityCanAnimateOnImplThread() const {
+  return scrollbar_->IsOverlay();
+}
+
+ScrollbarOrientation ScrollbarLayer::Orientation() const {
+  return scrollbar_->Orientation();
+}
+
+int ScrollbarLayer::MaxTextureSize() {
+  DCHECK(layer_tree_host());
+  return layer_tree_host()->GetRendererCapabilities().max_texture_size;
+}
+
+float ScrollbarLayer::ClampScaleToMaxTextureSize(float scale) {
+  if (layer_tree_host()->settings().solid_color_scrollbars)
+    return scale;
+
+  // If the scaled content_bounds() is bigger than the max texture size of the
+  // device, we need to clamp it by rescaling, since content_bounds() is used
+  // below to set the texture size.
+  gfx::Size scaled_bounds = ComputeContentBoundsForScale(scale, scale);
+  if (scaled_bounds.width() > MaxTextureSize() ||
+      scaled_bounds.height() > MaxTextureSize()) {
+    if (scaled_bounds.width() > scaled_bounds.height())
+      return (MaxTextureSize() - 1) / static_cast<float>(bounds().width());
+    else
+      return (MaxTextureSize() - 1) / static_cast<float>(bounds().height());
+  }
+  return scale;
+}
+
+void ScrollbarLayer::CalculateContentsScale(float ideal_contents_scale,
+                                            float device_scale_factor,
+                                            float page_scale_factor,
+                                            bool animating_transform_to_screen,
+                                            float* contents_scale_x,
+                                            float* contents_scale_y,
+                                            gfx::Size* content_bounds) {
+  ContentsScalingLayer::CalculateContentsScale(
+      ClampScaleToMaxTextureSize(ideal_contents_scale),
+      device_scale_factor,
+      page_scale_factor,
+      animating_transform_to_screen,
+      contents_scale_x,
+      contents_scale_y,
+      content_bounds);
+}
+
+void ScrollbarLayer::PushPropertiesTo(LayerImpl* layer) {
+  ContentsScalingLayer::PushPropertiesTo(layer);
+
+  ScrollbarLayerImpl* scrollbar_layer = static_cast<ScrollbarLayerImpl*>(layer);
+
+  if (layer_tree_host() &&
+      layer_tree_host()->settings().solid_color_scrollbars) {
+    int thickness_override =
+      layer_tree_host()->settings().solid_color_scrollbar_thickness_dip;
+    if (thickness_override != -1) {
+      scrollbar_layer->set_thumb_thickness(thickness_override);
+    } else {
+      if (Orientation() == HORIZONTAL)
+        scrollbar_layer->set_thumb_thickness(bounds().height());
+      else
+        scrollbar_layer->set_thumb_thickness(bounds().width());
+    }
+  } else {
+    scrollbar_layer->set_thumb_thickness(thumb_thickness_);
+  }
+  scrollbar_layer->set_thumb_length(thumb_length_);
+
+  if (Orientation() == HORIZONTAL) {
+    scrollbar_layer->set_track_start(track_rect_.x());
+    scrollbar_layer->set_track_length(track_rect_.width());
+  } else {
+    scrollbar_layer->set_track_start(track_rect_.y());
+    scrollbar_layer->set_track_length(track_rect_.height());
+  }
+
+  if (track_ui_resource_status_ == UIResourceManagerClient::READY) {
+    scrollbar_layer->set_track_ui_resource_id(track_ui_resource_id_);
+  } else {
+    scrollbar_layer->set_track_ui_resource_id(0);
+  }
+
+  if (thumb_ui_resource_status_ == UIResourceManagerClient::READY) {
+    scrollbar_layer->set_thumb_ui_resource_id(thumb_ui_resource_id_);
+  } else {
+    scrollbar_layer->set_thumb_ui_resource_id(0);
+  }
+}
+
+ScrollbarLayer* ScrollbarLayer::ToScrollbarLayer() {
+  return this;
+}
+
+void ScrollbarLayer::SetLayerTreeHost(LayerTreeHost* host) {
+  ContentsScalingLayer::SetLayerTreeHost(host);
+}
+
+gfx::Rect ScrollbarLayer::ScrollbarLayerRectToContentRect(
+    gfx::Rect layer_rect) const {
+  // Don't intersect with the bounds as in LayerRectToContentRect() because
+  // layer_rect here might be in coordinates of the containing layer.
+  gfx::Rect expanded_rect = gfx::ScaleToEnclosingRect(
+      layer_rect, contents_scale_y(), contents_scale_y());
+  // We should never return a rect bigger than the content_bounds().
+  gfx::Size clamped_size = expanded_rect.size();
+  clamped_size.SetToMin(content_bounds());
+  expanded_rect.set_size(clamped_size);
+  return expanded_rect;
+}
+
+void ScrollbarLayer::Update(ResourceUpdateQueue* queue,
+                            const OcclusionTracker* occlusion) {
+  track_rect_ = scrollbar_->TrackRect();
+
+  if (layer_tree_host()->settings().solid_color_scrollbars)
+    return;
+
+  base::AutoReset<bool> ignore_set_needs_commit(&ignore_set_needs_commit_,
+                                                true);
+  ContentsScalingLayer::Update(queue, occlusion);
+
+  if (scrollbar_->HasThumb()) {
+    thumb_thickness_ = scrollbar_->ThumbThickness();
+    thumb_length_ = scrollbar_->ThumbLength();
+    gfx::Rect origin_thumb_rect = OriginThumbRect();
+  }
+
+  if (skip_update_) {
+    skip_update_ = false;
+    return;
+  }
+
+  gfx::Rect track_rect = ScrollbarLayerRectToContentRect(
+      gfx::Rect(scrollbar_->Location(), bounds()));
+  gfx::Rect thumb_rect = OriginThumbRect();
+
+  {
+    track_bitmap_ = UIResourceBitmap::Create(
+        new uint8_t[track_rect.width()*track_rect.height()*4],
+        UIResourceBitmap::RGBA8,
+        track_rect.size());
+
+    // raster track
+    skia::RefPtr<SkCanvas> track_canvas = skia::AdoptRef(
+        skia::CreatePlatformCanvas(track_rect.width(),
+                                   track_rect.height(),
+                                   false,
+                                   reinterpret_cast<uint8_t*>(
+                                       track_bitmap_->GetPixels()),
+                                   skia::CRASH_ON_FAILURE));
+
+    track_canvas->save();
+    track_canvas->translate(SkFloatToScalar(-track_rect.x()),
+                            SkFloatToScalar(-track_rect.y()));
+    SkPaint paint;
+    paint.setAntiAlias(false);
+    paint.setXfermodeMode(SkXfermode::kClear_Mode);
+    SkRect layer_sk_rect = SkRect::MakeXYWH(track_rect.x(),
+                                            track_rect.y(),
+                                            track_rect.width(),
+                                            track_rect.height());
+
+    track_canvas->drawRect(layer_sk_rect, paint);
+    track_canvas->clipRect(layer_sk_rect);
+    scrollbar_->PaintPart(track_canvas.get(), TRACK, track_rect);
+    track_canvas->restore();
+
+    if (track_ui_resource_id_) {
+      layer_tree_host()->DeleteUIResource(track_ui_resource_id_);
+    }
+    track_ui_resource_id_ = layer_tree_host()->CreateUIResource(track_bitmap_,
+                                                                this);
+  }
+
+  if (scrollbar_->HasThumb()) {
+    thumb_bitmap_ = UIResourceBitmap::Create(
+        new uint8_t[thumb_rect.width()*thumb_rect.height()*4],
+        UIResourceBitmap::RGBA8,
+        thumb_rect.size());
+
+    // raster thumb
+    skia::RefPtr<SkCanvas> thumb_canvas = skia::AdoptRef(
+        skia::CreatePlatformCanvas(thumb_rect.width(),
+                                   thumb_rect.height(),
+                                   false,
+                                   reinterpret_cast<uint8_t*>(
+                                       thumb_bitmap_->GetPixels()),
+                                   skia::CRASH_ON_FAILURE));
+
+    scrollbar_->PaintPart(thumb_canvas.get(),
+                          THUMB,
+                          thumb_rect);
+
+    if (thumb_ui_resource_id_)
+      layer_tree_host()->DeleteUIResource(thumb_ui_resource_id_);
+    thumb_ui_resource_id_ = layer_tree_host()->CreateUIResource(thumb_bitmap_,
+                                                                this);
+  }
+}
+
+gfx::Rect ScrollbarLayer::OriginThumbRect() const {
+  gfx::Size thumb_size;
+  if (Orientation() == HORIZONTAL) {
+    thumb_size = gfx::Size(scrollbar_->ThumbLength(),
+                           scrollbar_->ThumbThickness());
+  } else {
+    thumb_size = gfx::Size(scrollbar_->ThumbThickness(),
+                           scrollbar_->ThumbLength());
+  }
+  return ScrollbarLayerRectToContentRect(gfx::Rect(thumb_size));
+}
+
+void ScrollbarLayer::UIResourceReady(UIResourceId id) {
+  if (thumb_ui_resource_id_ == id) {
+    thumb_ui_resource_status_ = UIResourceManagerClient::READY;
+    // need to push the ui resource id to the impl thread.
+    // Is this the only way?

[enne (OOO), 2013/07/09 17:57:48]

I think you're looking for SetNeedsCommit.

[powei, 2013/07/10 17:47:21]

Done.

+    SetNeedsDisplay();
+    // if we do not have this flag, we will always have a
+    // setneedsdisplay request in the scheduler
+    skip_update_ = true;
+  }
+
+  if (track_ui_resource_id_ == id) {
+    track_ui_resource_status_ = UIResourceManagerClient::READY;
+    SetNeedsDisplay();
+    skip_update_ = true;
+  }
+}
+
+void ScrollbarLayer::UIResourceLost(UIResourceId id) {

[enne (OOO), 2013/07/09 17:57:48]

As I mentioned in the doc about this, I would really prefer that the UI resource
manager handle this and not individual layer types.

That way individual layers could just persist ui resource ids that wouldn't ever
need to change unless the resource changed.  Create resource could pass a
callback to recreate these resources initially or in the future when needed.

[aelias_OOO_until_Jul13, 2013/07/09 20:22:19]

OK, after discussing it with dtrainor@, we agree.  Let's change to that
approach.  The only condition is that it should be allowed to reupload a
resource of a different size from the original, so that a low-res version or 1x1
placeholder can be uploaded.

+  if (thumb_ui_resource_id_ == id)
+    thumb_ui_resource_status_ = UIResourceManagerClient::LOST;
+  thumb_ui_resource_id_ = 0;
+
+  if (track_ui_resource_id_ == id)
+    track_ui_resource_status_ = UIResourceManagerClient::LOST;
+  track_ui_resource_id_ = 0;
+}
+
+}  // namespace cc
+
+#endif