1 files changed, 61 insertions, 0 deletions
diff --git a/gfx/2d/HelpersWinFonts.h b/gfx/2d/HelpersWinFonts.h
new file mode 100644
index 000000000..cd84070d4
--- /dev/null
+++ b/gfx/2d/HelpersWinFonts.h
@@ -0,0 +1,61 @@
+/* -*- Mode: C++; tab-width: 20; indent-tabs-mode: nil; c-basic-offset: 2 -*-
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+namespace mozilla {
+namespace gfx {
+
+// Cleartype can be dynamically enabled/disabled, so we have to check it
+// everytime we want to render some text.
+static BYTE
+GetSystemTextQuality()
+{
+  BOOL font_smoothing;
+  UINT smoothing_type;
+
+  if (!SystemParametersInfo(SPI_GETFONTSMOOTHING, 0, &font_smoothing, 0)) {
+    return DEFAULT_QUALITY;
+  }
+
+  if (font_smoothing) {
+      if (!SystemParametersInfo(SPI_GETFONTSMOOTHINGTYPE,
+                                0, &smoothing_type, 0)) {
+        return DEFAULT_QUALITY;
+      }
+
+      if (smoothing_type == FE_FONTSMOOTHINGCLEARTYPE) {
+        return CLEARTYPE_QUALITY;
+      }
+
+      return ANTIALIASED_QUALITY;
+  }
+
+  return DEFAULT_QUALITY;
+}
+
+static AntialiasMode
+GetSystemDefaultAAMode()
+{
+  AntialiasMode defaultMode = AntialiasMode::SUBPIXEL;
+  if (gfxPrefs::DisableAllTextAA()) {
+    return AntialiasMode::NONE;
+  }
+
+  switch (GetSystemTextQuality()) {
+  case CLEARTYPE_QUALITY:
+    defaultMode = AntialiasMode::SUBPIXEL;
+    break;
+  case ANTIALIASED_QUALITY:
+    defaultMode = AntialiasMode::GRAY;
+    break;
+  case DEFAULT_QUALITY:
+    defaultMode = AntialiasMode::NONE;
+    break;
+  }
+
+  return defaultMode;
+}
+
+} // namespace gfx
+} // namespace mozilla