blob: 968f998634bf157739d803994d6d2703ec410b62 [file] [log] [blame]
// 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 "base/bind.h"
#include "base/bind_helpers.h"
#include "base/files/file_path.h"
#include "base/memory/scoped_ptr.h"
#include "base/memory/singleton.h"
#include "base/win/registry.h"
#include "ui/gfx/font_render_params.h"
#include "ui/gfx/win/direct_write.h"
#include "ui/gfx/win/singleton_hwnd_observer.h"
namespace gfx {
namespace {
FontRenderParams::SubpixelRendering GetSubpixelRenderingGeometry() {
DISPLAY_DEVICE display_device = {sizeof(DISPLAY_DEVICE)};
for (int i = 0; EnumDisplayDevices(nullptr, i, &display_device, 0); ++i) {
// TODO(scottmg): We only support the primary device currently.
if (display_device.StateFlags & DISPLAY_DEVICE_PRIMARY_DEVICE) {
base::FilePath trimmed =
base::FilePath(display_device.DeviceName).BaseName();
base::win::RegKey key(
HKEY_LOCAL_MACHINE,
(L"SOFTWARE\\Microsoft\\Avalon.Graphics\\" + trimmed.value()).c_str(),
KEY_READ);
DWORD pixel_structure;
if (key.ReadValueDW(L"PixelStructure", &pixel_structure) ==
ERROR_SUCCESS) {
if (pixel_structure == 1)
return FontRenderParams::SUBPIXEL_RENDERING_RGB;
if (pixel_structure == 2)
return FontRenderParams::SUBPIXEL_RENDERING_BGR;
}
break;
}
}
// No explicit ClearType settings, default to RGB.
return FontRenderParams::SUBPIXEL_RENDERING_RGB;
}
// Caches font render params and updates them on system notifications.
class CachedFontRenderParams {
public:
static CachedFontRenderParams* GetInstance() {
return Singleton<CachedFontRenderParams>::get();
}
const FontRenderParams& GetParams() {
if (params_)
return *params_;
params_.reset(new FontRenderParams());
params_->antialiasing = false;
params_->subpixel_positioning = false;
params_->autohinter = false;
params_->use_bitmaps = false;
params_->hinting = FontRenderParams::HINTING_MEDIUM;
params_->subpixel_rendering = FontRenderParams::SUBPIXEL_RENDERING_NONE;
BOOL enabled = false;
if (SystemParametersInfo(SPI_GETFONTSMOOTHING, 0, &enabled, 0) && enabled) {
params_->antialiasing = true;
// GDI does not support subpixel positioning.
params_->subpixel_positioning = win::IsDirectWriteEnabled();
UINT type = 0;
if (SystemParametersInfo(SPI_GETFONTSMOOTHINGTYPE, 0, &type, 0) &&
type == FE_FONTSMOOTHINGCLEARTYPE) {
params_->subpixel_rendering = GetSubpixelRenderingGeometry();
}
}
singleton_hwnd_observer_.reset(new SingletonHwndObserver(
base::Bind(&CachedFontRenderParams::OnWndProc,
base::Unretained(this))));
return *params_;
}
private:
friend struct DefaultSingletonTraits<CachedFontRenderParams>;
CachedFontRenderParams() {}
~CachedFontRenderParams() {}
void OnWndProc(HWND hwnd, UINT message, WPARAM wparam, LPARAM lparam) {
if (message == WM_SETTINGCHANGE) {
params_.reset();
singleton_hwnd_observer_.reset(nullptr);
}
}
scoped_ptr<FontRenderParams> params_;
scoped_ptr<SingletonHwndObserver> singleton_hwnd_observer_;
DISALLOW_COPY_AND_ASSIGN(CachedFontRenderParams);
};
} // namespace
FontRenderParams GetFontRenderParams(const FontRenderParamsQuery& query,
std::string* family_out) {
if (family_out)
NOTIMPLEMENTED();
// Customized font rendering settings are not supported, only defaults.
return CachedFontRenderParams::GetInstance()->GetParams();
}
} // namespace gfx