Index: ui/gfx/win/direct_write.cc |
diff --git a/ui/gfx/win/direct_write.cc b/ui/gfx/win/direct_write.cc |
new file mode 100644 |
index 0000000000000000000000000000000000000000..fcc185c433dc17acdd1151b34ed421d05e80c18b |
--- /dev/null |
+++ b/ui/gfx/win/direct_write.cc |
@@ -0,0 +1,48 @@ |
+// 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 "ui/gfx/win/direct_write.h" |
+ |
+#include "base/basictypes.h" |
+#include "base/command_line.h" |
+#include "base/metrics/field_trial.h" |
+#include "base/win/windows_version.h" |
+#include "ui/gfx/switches.h" |
+#include "ui/gfx/win/dpi.h" |
+ |
+namespace gfx { |
+namespace win { |
+ |
+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 |