Respect the system ClearType setting in RenderTextWin.

BUG=113184, 105550
TEST=Build Chrome Windows with gyp flag use_canvas_skia_skia=1. Open Chrome and observe text rendering in the tab strip, bookmarks bar, etc. Change Windows ClearType settings while Chrome is running. Text rendering should be updated appropriately.

Review URL: http://codereview.chromium.org/9370026

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@122514 0039d316-1c4b-4281-b951-d872f2087c98

8 files changed, 297 insertions, 0 deletions

diff --git a/ui/base/win/singleton_hwnd.cc b/ui/base/win/singleton_hwnd.cc
new file mode 100644
index 0000000..7132be3
--- /dev/null
+++ b/ui/base/win/singleton_hwnd.cc
@@ -0,0 +1,81 @@
+// Copyright (c) 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 "ui/base/win/singleton_hwnd.h"
+
+#include "base/memory/singleton.h"
+#include "base/process_util.h"
+#include "base/win/wrapped_window_proc.h"
+#include "ui/base/win/hwnd_util.h"
+
+namespace {
+
+// Windows class name to use for the listener window.
+const wchar_t kWindowClassName[] = L"Chrome_SingletonHwnd";
+
+// Windows callback for listening for WM_* messages.
+LRESULT CALLBACK ListenerWindowProc(HWND hwnd,
+                                    UINT message,
+                                    WPARAM wparam,
+                                    LPARAM lparam) {
+  ui::SingletonHwnd::GetInstance()->OnWndProc(hwnd, message, wparam, lparam);
+  return ::DefWindowProc(hwnd, message, wparam, lparam);
+}
+
+// Creates a listener window to receive WM_* messages.
+HWND CreateListenerWindow() {
+  WNDCLASSEX wc = {0};
+  wc.cbSize = sizeof(wc);
+  wc.lpfnWndProc = base::win::WrappedWindowProc<ListenerWindowProc>;
+  wc.hInstance = base::GetModuleFromAddress(&ListenerWindowProc);
+  wc.lpszClassName = kWindowClassName;
+  ATOM window_class = ::RegisterClassEx(&wc);
+  DCHECK(window_class);
+
+  return ::CreateWindow(MAKEINTATOM(window_class), 0, 0, 0, 0, 0, 0, 0, 0,
+                        wc.hInstance, 0);
+}
+
+}  // namespace
+
+namespace ui {
+
+// static
+SingletonHwnd* SingletonHwnd::GetInstance() {
+  return Singleton<SingletonHwnd>::get();
+}
+
+void SingletonHwnd::AddObserver(Observer* observer) {
+  if (!listener_window_) {
+    listener_window_ = CreateListenerWindow();
+    ui::CheckWindowCreated(listener_window_);
+  }
+  observer_list_.AddObserver(observer);
+}
+
+void SingletonHwnd::RemoveObserver(Observer* observer) {
+  observer_list_.RemoveObserver(observer);
+}
+
+void SingletonHwnd::OnWndProc(HWND hwnd,
+                              UINT message,
+                              WPARAM wparam,
+                              LPARAM lparam) {
+  FOR_EACH_OBSERVER(Observer,
+                    observer_list_,
+                    OnWndProc(hwnd, message, wparam, lparam));
+}
+
+SingletonHwnd::SingletonHwnd()
+    : listener_window_(NULL) {
+}
+
+SingletonHwnd::~SingletonHwnd() {
+  if (listener_window_) {
+    ::DestroyWindow(listener_window_);
+    ::UnregisterClass(kWindowClassName, GetModuleHandle(NULL));
+  }
+}
+
+}  // namespace ui
diff --git a/ui/base/win/singleton_hwnd.h b/ui/base/win/singleton_hwnd.h
new file mode 100644
index 0000000..49fb209
--- /dev/null
+++ b/ui/base/win/singleton_hwnd.h
@@ -0,0 +1,59 @@
+// Copyright (c) 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.
+
+#ifndef UI_BASE_WIN_SINGLETON_HWND_H_
+#define UI_BASE_WIN_SINGLETON_HWND_H_
+#pragma once
+
+#include <windows.h>
+#include <vector>
+
+#include "base/basictypes.h"
+#include "base/callback_forward.h"
+#include "base/observer_list.h"
+
+template<typename T> struct DefaultSingletonTraits;
+
+namespace ui {
+
+// Singleton message-only HWND that allows interested clients to receive WM_*
+// notifications.
+class SingletonHwnd {
+ public:
+  static SingletonHwnd* GetInstance();
+
+  // Observer interface for receiving Windows WM_* notifications.
+  class Observer {
+   public:
+    virtual void OnWndProc(HWND hwnd,
+                           UINT message,
+                           WPARAM wparam,
+                           LPARAM lparam) = 0;
+  };
+
+  // Add/remove observer to receive WM_* notifications.
+  void AddObserver(Observer* observer);
+  void RemoveObserver(Observer* observer);
+
+  // Windows callback for WM_* notifications.
+  void OnWndProc(HWND hwnd, UINT message, WPARAM wparam, LPARAM lparam);
+
+ private:
+  friend struct DefaultSingletonTraits<SingletonHwnd>;
+
+  SingletonHwnd();
+  ~SingletonHwnd();
+
+  // Listener HWND for WM_* notifications.
+  HWND listener_window_;
+
+  // List of registered observers.
+  ObserverList<Observer> observer_list_;
+
+  DISALLOW_COPY_AND_ASSIGN(SingletonHwnd);
+};
+
+}  // namespace ui
+
+#endif  // UI_BASE_WIN_SINGLETON_HWND_H_
diff --git a/ui/gfx/font_smoothing_win.cc b/ui/gfx/font_smoothing_win.cc
new file mode 100644
index 0000000..a4be729
--- /dev/null
+++ b/ui/gfx/font_smoothing_win.cc
@@ -0,0 +1,121 @@
+// Copyright (c) 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 "ui/gfx/font_smoothing_win.h"
+
+#include "base/memory/singleton.h"
+#include "ui/base/win/singleton_hwnd.h"
+
+namespace {
+
+// Helper class to cache font smoothing settings and listen for notifications
+// to re-query them from the system.
+class CachedFontSmoothingSettings : public ui::SingletonHwnd::Observer {
+ public:
+  static CachedFontSmoothingSettings* GetInstance();
+
+  // Returns the cached Windows font smoothing settings. Queries the settings
+  // via Windows APIs and begins listening for changes when called for the
+  // first time.
+  void GetFontSmoothingSettings(bool* smoothing_enabled,
+                                bool* cleartype_enabled);
+
+ private:
+  friend struct DefaultSingletonTraits<CachedFontSmoothingSettings>;
+
+  CachedFontSmoothingSettings();
+  virtual ~CachedFontSmoothingSettings();
+
+  // Listener for WM_SETTINGCHANGE notifications.
+  virtual void OnWndProc(HWND hwnd,
+                         UINT message,
+                         WPARAM wparam,
+                         LPARAM lparam) OVERRIDE;
+
+  // Queries the font settings from the system.
+  void QueryFontSettings();
+
+  // Indicates whether the MessagePumpObserver has been registered.
+  bool observer_added_;
+
+  // Indicates whether |smoothing_enabled_| and |cleartype_enabled_| are valid
+  // or need to be re-queried from the system.
+  bool need_to_query_settings_;
+
+  // Indicates that font smoothing is enabled.
+  bool smoothing_enabled_;
+
+  // Indicates that the ClearType font smoothing is enabled.
+  bool cleartype_enabled_;
+
+  DISALLOW_COPY_AND_ASSIGN(CachedFontSmoothingSettings);
+};
+
+// static
+CachedFontSmoothingSettings* CachedFontSmoothingSettings::GetInstance() {
+  return Singleton<CachedFontSmoothingSettings>::get();
+}
+
+void CachedFontSmoothingSettings::GetFontSmoothingSettings(
+    bool* smoothing_enabled,
+    bool* cleartype_enabled) {
+  // If cached settings are stale, query them from the OS.
+  if (need_to_query_settings_) {
+    QueryFontSettings();
+    need_to_query_settings_ = false;
+  }
+  if (!observer_added_) {
+    ui::SingletonHwnd::GetInstance()->AddObserver(this);
+    observer_added_ = true;
+  }
+  *smoothing_enabled = smoothing_enabled_;
+  *cleartype_enabled = cleartype_enabled_;
+}
+
+CachedFontSmoothingSettings::CachedFontSmoothingSettings()
+    : observer_added_(false),
+      need_to_query_settings_(true),
+      smoothing_enabled_(false),
+      cleartype_enabled_(false) {
+}
+
+CachedFontSmoothingSettings::~CachedFontSmoothingSettings() {
+  // Can't remove the SingletonHwnd observer here since SingletonHwnd may have
+  // been destroyed already (both singletons).
+}
+
+void CachedFontSmoothingSettings::OnWndProc(HWND hwnd,
+                                            UINT message,
+                                            WPARAM wparam,
+                                            LPARAM lparam) {
+  if (message == WM_SETTINGCHANGE)
+    need_to_query_settings_ = true;
+}
+
+void CachedFontSmoothingSettings::QueryFontSettings() {
+  smoothing_enabled_ = false;
+  cleartype_enabled_ = false;
+
+  BOOL enabled = false;
+  if (SystemParametersInfo(SPI_GETFONTSMOOTHING, 0, &enabled, 0) && enabled) {
+    smoothing_enabled_ = true;
+
+    UINT smooth_type = 0;
+    if (SystemParametersInfo(SPI_GETFONTSMOOTHINGTYPE, 0, &smooth_type, 0))
+      cleartype_enabled_ = (smooth_type == FE_FONTSMOOTHINGCLEARTYPE);
+  }
+}
+
+}  // namespace
+
+namespace gfx {
+
+void GetCachedFontSmoothingSettings(bool* smoothing_enabled,
+                                    bool* cleartype_enabled) {
+  CachedFontSmoothingSettings::GetInstance()->GetFontSmoothingSettings(
+      smoothing_enabled,
+      cleartype_enabled);
+}
+
+}  // namespace gfx
diff --git a/ui/gfx/font_smoothing_win.h b/ui/gfx/font_smoothing_win.h
new file mode 100644
index 0000000..2ab6688
--- /dev/null
+++ b/ui/gfx/font_smoothing_win.h
@@ -0,0 +1,17 @@
+// Copyright (c) 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.
+
+#ifndef UI_GFX_FONT_SMOOTHING_WIN_H_
+#define UI_GFX_FONT_SMOOTHING_WIN_H_
+#pragma once
+
+namespace gfx {
+
+// Returns the Windows system font smoothing and ClearType settings.
+void GetCachedFontSmoothingSettings(bool* smoothing_enabled,
+                                    bool* cleartype_enabled);
+
+}  // namespace gfx
+
+#endif  // UI_GFX_FONT_SMOOTHING_WIN_H_
diff --git a/ui/gfx/render_text.cc b/ui/gfx/render_text.cc
index 5b9b8c4..80550c3 100644
--- a/ui/gfx/render_text.cc
+++ b/ui/gfx/render_text.cc
@@ -185,6 +185,13 @@ SkiaTextRenderer::SkiaTextRenderer(Canvas* canvas)
 SkiaTextRenderer::~SkiaTextRenderer() {
 }
 
+void SkiaTextRenderer::SetFontSmoothingSettings(bool enable_smoothing,
+                                                bool enable_lcd_text) {
+  paint_.setAntiAlias(enable_smoothing);
+  paint_.setSubpixelText(enable_smoothing);
+  paint_.setLCDRenderText(enable_lcd_text);
+}
+
 void SkiaTextRenderer::SetTypeface(SkTypeface* typeface) {
   paint_.setTypeface(typeface);
 }
diff --git a/ui/gfx/render_text.h b/ui/gfx/render_text.h
index db98b84..2498bcb 100644
--- a/ui/gfx/render_text.h
+++ b/ui/gfx/render_text.h
@@ -37,6 +37,7 @@ class SkiaTextRenderer {
   explicit SkiaTextRenderer(Canvas* canvas);
   ~SkiaTextRenderer();
 
+  void SetFontSmoothingSettings(bool enable_smoothing, bool enable_lcd_text);
   void SetTypeface(SkTypeface* typeface);
   void SetTextSize(int size);
   void SetFont(const gfx::Font& font);
diff --git a/ui/gfx/render_text_win.cc b/ui/gfx/render_text_win.cc
index 36cd23b..608cc7d 100644
--- a/ui/gfx/render_text_win.cc
+++ b/ui/gfx/render_text_win.cc
@@ -11,6 +11,7 @@
 #include "base/stl_util.h"
 #include "base/string_util.h"
 #include "base/utf_string_conversions.h"
+#include "ui/gfx/font_smoothing_win.h"
 #include "ui/gfx/canvas.h"
 #include "ui/gfx/canvas_skia.h"
 #include "ui/gfx/platform_font.h"
@@ -441,6 +442,12 @@ void RenderTextWin::DrawVisualText(Canvas* canvas) {
   internal::SkiaTextRenderer renderer(canvas);
   ApplyFadeEffects(&renderer);
 
+  bool smoothing_enabled;
+  bool cleartype_enabled;
+  GetCachedFontSmoothingSettings(&smoothing_enabled, &cleartype_enabled);
+  // Note that |cleartype_enabled| corresponds to Skia's |enable_lcd_text|.
+  renderer.SetFontSmoothingSettings(smoothing_enabled, cleartype_enabled);
+
   for (size_t i = 0; i < runs_.size(); ++i) {
     // Get the run specified by the visual-to-logical map.
     internal::TextRun* run = runs_[visual_to_logical_[i]];
diff --git a/ui/ui.gyp b/ui/ui.gyp
index e8a57a9..28bd730 100644
--- a/ui/ui.gyp
+++ b/ui/ui.gyp
@@ -220,6 +220,8 @@
         'base/win/mouse_wheel_util.h',
         'base/win/shell.cc',
         'base/win/shell.h',
+        'base/win/singleton_hwnd.cc',
+        'base/win/singleton_hwnd.h',
         'base/win/window_impl.cc',
         'base/win/window_impl.h',
         'base/x/active_window_watcher_x.cc',
@@ -261,6 +263,8 @@
         'gfx/font.cc',
         'gfx/font_list.h',
         'gfx/font_list.cc',
+        'gfx/font_smoothing_win.cc',
+        'gfx/font_smoothing_win.h',
         'gfx/gfx_paths.cc',
         'gfx/gfx_paths.h',
         'gfx/image/image.cc',