Implement cursor compositing mode on Ash

ash/display/cursor_window_controller.cc

Index: ash/display/cursor_window_controller.cc
diff --git a/ash/display/cursor_window_controller.cc b/ash/display/cursor_window_controller.cc
new file mode 100644
index 0000000000000000000000000000000000000000..a9bbf877c72694e879a2a5643e7b758b3ef70e55
--- /dev/null
+++ b/ash/display/cursor_window_controller.cc
@@ -0,0 +1,237 @@
+// Copyright 2014 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 "ash/display/cursor_window_controller.h"
+
+#include "ash/shell.h"
+#include "ui/aura/env.h"
+#include "ui/aura/root_window.h"
+#include "ui/aura/window_delegate.h"
+#include "ui/base/cursor/cursors_aura.h"
+#include "ui/base/hit_test.h"
+#include "ui/base/resource/resource_bundle.h"
+#include "ui/compositor/dip_util.h"
+#include "ui/gfx/canvas.h"
+#include "ui/gfx/display.h"
+#include "ui/gfx/image/image_skia.h"
+#include "ui/gfx/image/image_skia_operations.h"
+
+namespace ash {
+namespace internal {
+
+class CursorWindowDelegate : public aura::WindowDelegate {
+ public:
+  CursorWindowDelegate() : is_cursor_compositing_enabled_(false) {}
+  virtual ~CursorWindowDelegate() {}
+
+  // aura::WindowDelegate overrides:
+  virtual gfx::Size GetMinimumSize() const OVERRIDE { return size_; }
+  virtual gfx::Size GetMaximumSize() const OVERRIDE { return size_; }
+  virtual void OnBoundsChanged(const gfx::Rect& old_bounds,
+                               const gfx::Rect& new_bounds) OVERRIDE {}
+  virtual gfx::NativeCursor GetCursor(const gfx::Point& point) OVERRIDE {
+    return gfx::kNullCursor;
+  }
+  virtual int GetNonClientComponent(
+      const gfx::Point& point) const OVERRIDE {
+    return HTNOWHERE;
+  }
+  virtual bool ShouldDescendIntoChildForEventHandling(
+      aura::Window* child,
+      const gfx::Point& location) OVERRIDE {
+    return false;
+  }
+  virtual bool CanFocus() OVERRIDE { return false; }
+  virtual void OnCaptureLost() OVERRIDE {}
+  virtual void OnPaint(gfx::Canvas* canvas) OVERRIDE {
+    canvas->DrawImageInt(cursor_image_, 0, 0);
+  }
+  virtual void OnDeviceScaleFactorChanged(
+      float device_scale_factor) OVERRIDE {}
+  virtual void OnWindowDestroying() OVERRIDE {}
+  virtual void OnWindowDestroyed() OVERRIDE {}
+  virtual void OnWindowTargetVisibilityChanged(bool visible) OVERRIDE {}
+  virtual bool HasHitTestMask() const OVERRIDE { return false; }
+  virtual void GetHitTestMask(gfx::Path* mask) const OVERRIDE {}
+  virtual void DidRecreateLayer(ui::Layer* old_layer,
+                                ui::Layer* new_layer) OVERRIDE {}
+
+  // Sets cursor compositing mode on/off.
+  void SetCursorCompositingEnabled(bool enabled) {
+    is_cursor_compositing_enabled_ = enabled;
+  }
+
+  // Sets the cursor image for the |display|'s scale factor.
+  void SetCursorImage(const gfx::ImageSkia& image,
+                      const gfx::Display& display) {
+    float scale_factor = display.device_scale_factor();
+    const gfx::ImageSkiaRep& image_rep = image.GetRepresentation(scale_factor);
+    if (!is_cursor_compositing_enabled_) {
+      // Note that mirror window's scale factor is always 1.0f, therefore we
+      // need to take 2x's image and paint as if it's 1x image.
+      size_ = image_rep.pixel_size();
+      cursor_image_ = gfx::ImageSkia::CreateFrom1xBitmap(image_rep.sk_bitmap());
+    } else {
+      size_ = image.size();
+      cursor_image_ = gfx::ImageSkia(
+          gfx::ImageSkiaRep(image_rep.sk_bitmap(), scale_factor));
+    }
+  }
+
+  const gfx::Size size() const { return size_; }
+
+ private:
+  bool is_cursor_compositing_enabled_;
+  gfx::ImageSkia cursor_image_;
+  gfx::Size size_;
+
+  DISALLOW_COPY_AND_ASSIGN(CursorWindowDelegate);
+};
+
+CursorWindowController::CursorWindowController()
+    : is_cursor_compositing_enabled_(false),
+      container_(NULL),
+      cursor_type_(ui::kCursorNone),
+      cursor_set_(ui::CURSOR_SET_NORMAL),
+      cursor_rotation_(gfx::Display::ROTATE_0),
+      delegate_(new CursorWindowDelegate()) {
+}
+
+CursorWindowController::~CursorWindowController() {
+  SetContainer(NULL);
+}
+
+void CursorWindowController::SetCursorCompositingEnabled(bool enabled) {
+  if (is_cursor_compositing_enabled_ != enabled) {
+    is_cursor_compositing_enabled_ = enabled;
+    delegate_->SetCursorCompositingEnabled(enabled);
+    UpdateCursorImage();
+  }
+}
+
+void CursorWindowController::SetContainer(aura::Window* container) {
+  if (container_ == container)
+    return;
+
+  container_ = container;
+  if (!container) {
+    cursor_window_.reset();
+    return;
+  }
+
+  if (!cursor_window_) {
+    cursor_window_.reset(new aura::Window(delegate_.get()));
+    cursor_window_->SetTransparent(true);
+    cursor_window_->Init(aura::WINDOW_LAYER_TEXTURED);
+    cursor_window_->set_ignore_events(true);
+    cursor_window_->set_owned_by_parent(false);
+  }
+
+  container->AddChild(cursor_window_.get());
+  cursor_window_->Show();
+  SetBoundsInScreen(container->bounds());
+}
+
+void CursorWindowController::SetBoundsInScreen(const gfx::Rect& bounds) {
+  bounds_in_screen_ = bounds;
+  UpdateLocation();
+}
+
+void CursorWindowController::UpdateLocation() {
+  if (!cursor_window_)
+    return;
+
+  gfx::Point point = aura::Env::GetInstance()->last_mouse_location();
+  if (!is_cursor_compositing_enabled_) {
+    Shell::GetPrimaryRootWindow()->GetDispatcher()->host()->ConvertPointToHost(
+        &point);
+  } else {
+    point.Offset(-bounds_in_screen_.x(), -bounds_in_screen_.y());
+  }
+  point.Offset(-hot_point_.x(), -hot_point_.y());
+  gfx::Rect bounds = cursor_window_->bounds();
+  bounds.set_origin(point);
+  cursor_window_->SetBounds(bounds);
+}
+
+void CursorWindowController::SetCursor(gfx::NativeCursor cursor) {
+  const gfx::Display& display = Shell::GetScreen()->GetPrimaryDisplay();
+  if (cursor_type_ == cursor.native_type() &&
+      cursor_rotation_ == display.rotation())
+    return;
+  cursor_type_ = cursor.native_type();
+  cursor_rotation_ = display.rotation();
+  UpdateCursorImage();
+}
+
+void CursorWindowController::SetCursorSet(ui::CursorSetType cursor_set) {
+  cursor_set_ = cursor_set;
+  UpdateCursorImage();
+}
+
+void CursorWindowController::SetVisibility(bool visible) {
+  if (!cursor_window_)
+    return;
+  if (visible)
+    cursor_window_->Show();
+  else
+    cursor_window_->Hide();
+}
+
+void CursorWindowController::UpdateCursorImage() {
+  const gfx::Display& display = Shell::GetScreen()->GetPrimaryDisplay();

[oshima, 2014/02/05 23:43:39]

hmm, this looks wrong. I guess you need to use cursor_window_/container_ to get
the Display?

[hshi1, 2014/02/06 00:48:44]

Done.

+  int resource_id;
+  // TODO(hshi): support custom cursor set.
+  bool success = ui::GetCursorDataFor(
+      cursor_set_,
+      cursor_type_,
+      display.device_scale_factor(),
+      &resource_id,
+      &hot_point_);
+  if (!success)
+    return;
+  const gfx::ImageSkia* image =
+      ResourceBundle::GetSharedInstance().GetImageSkiaNamed(resource_id);
+  gfx::ImageSkia rotated = *image;
+  if (!is_cursor_compositing_enabled_) {
+    switch (cursor_rotation_) {
+      case gfx::Display::ROTATE_0:
+        break;
+      case gfx::Display::ROTATE_90:
+        rotated = gfx::ImageSkiaOperations::CreateRotatedImage(
+            *image, SkBitmapOperations::ROTATION_90_CW);
+        hot_point_.SetPoint(
+            rotated.width() - hot_point_.y(),
+            hot_point_.x());
+        break;
+      case gfx::Display::ROTATE_180:
+        rotated = gfx::ImageSkiaOperations::CreateRotatedImage(
+            *image, SkBitmapOperations::ROTATION_180_CW);
+        hot_point_.SetPoint(
+            rotated.height() - hot_point_.x(),
+            rotated.width() - hot_point_.y());
+        break;
+      case gfx::Display::ROTATE_270:
+        rotated = gfx::ImageSkiaOperations::CreateRotatedImage(
+            *image, SkBitmapOperations::ROTATION_270_CW);
+        hot_point_.SetPoint(
+            hot_point_.y(),
+            rotated.height() - hot_point_.x());
+        break;
+    }
+  } else {
+    hot_point_ = ui::ConvertPointToDIP(Shell::GetPrimaryRootWindow()->layer(),
+                                       hot_point_);
+  }
+  delegate_->SetCursorImage(rotated, display);
+  if (cursor_window_) {
+    cursor_window_->SetBounds(gfx::Rect(delegate_->size()));
+    cursor_window_->SchedulePaintInRect(
+        gfx::Rect(cursor_window_->bounds().size()));
+    UpdateLocation();
+  }
+}
+
+}  // namespace internal
+}  // namespace ash