| Index: ui/gfx/win/dpi.cc
|
| diff --git a/ui/gfx/win/dpi.cc b/ui/gfx/win/dpi.cc
|
| index 88766ce2d4f6da8b12cf5a6e9c2298230dda9fd0..ae5db806084e681f3ea9e4e7d0b014a238a0b2a1 100644
|
| --- a/ui/gfx/win/dpi.cc
|
| +++ b/ui/gfx/win/dpi.cc
|
| @@ -6,6 +6,7 @@
|
|
|
| #include <windows.h>
|
| #include "base/command_line.h"
|
| +#include "base/metrics/field_trial.h"
|
| #include "base/win/scoped_hdc.h"
|
| #include "base/win/windows_version.h"
|
| #include "base/win/registry.h"
|
| @@ -228,5 +229,35 @@ bool IsDeviceScaleFactorSet() {
|
| return g_device_scale_factor != 0.0f;
|
| }
|
|
|
| +bool ShouldUseDirectWrite() {
|
| + // If the flag is currently on, and we're on Win7 or above, we enable
|
| + // DirectWrite. Skia does not require the additions to DirectWrite in QFE
|
| + // 2670838, but a simple 'better than XP' check is not enough.
|
| + if (base::win::GetVersion() < base::win::VERSION_WIN7)
|
| + return false;
|
| +
|
| + base::win::OSInfo::VersionNumber os_version =
|
| + base::win::OSInfo::GetInstance()->version_number();
|
| + if ((os_version.major == 6) && (os_version.minor == 1)) {
|
| + // We can't use DirectWrite for pre-release versions of Windows 7.
|
| + if (os_version.build < 7600)
|
| + return false;
|
| + }
|
| + // If forced off, don't use it.
|
| + const base::CommandLine& command_line =
|
| + *base::CommandLine::ForCurrentProcess();
|
| + if (command_line.HasSwitch(switches::kDisableDirectWrite))
|
| + return false;
|
| +
|
| + // Can't use GDI on HiDPI.
|
| + if (gfx::GetDPIScale() > 1.0f)
|
| + return true;
|
| +
|
| + // Otherwise, check the field trial.
|
| + const std::string group_name =
|
| + base::FieldTrialList::FindFullName("DirectWrite");
|
| + return group_name != "Disabled";
|
| +}
|
| +
|
| } // namespace win
|
| } // namespace gfx
|
|
|