Changeset 219422 in webkit

Timestamp:

Jul 12, 2017 1:44:41 PM (7 years ago)

Author:

commit-queue@webkit.org

Message:

[FreeType] Enable BCI on webfonts
​https://bugs.webkit.org/show_bug.cgi?id=174403

Patch by Alicia Boya García <​aboya@igalia.com> on 2017-07-12
Reviewed by Michael Catanzaro.

The FreeType BCI hinter used to be disabled on webfonts in favor of
the autohinter.

FreeType BCI hinter has improved considerably in the past and now most
other browsers enable it too. Given the old reasons no longer apply,
the BCI has now been enabled in order to get better text rendering when
embedded hints are available.

• platform/graphics/freetype/FontCustomPlatformDataFreeType.cpp:

(WebCore::FontCustomPlatformData::FontCustomPlatformData):

Location:

trunk/Source/WebCore

Files:

• ChangeLog (modified) (1 diff)
• platform/graphics/freetype/FontCustomPlatformDataFreeType.cpp (modified) (1 diff)

trunk/Source/WebCore/ChangeLog

@@ +1 @@
+2017-07-12  Alicia Boya García  <aboya@igalia.com>
+
+        [FreeType] Enable BCI on webfonts
+        https://bugs.webkit.org/show_bug.cgi?id=174403
+
+        Reviewed by Michael Catanzaro.
+
+        The FreeType BCI hinter used to be disabled on webfonts in favor of
+        the autohinter.
+
+        FreeType BCI hinter has improved considerably in the past and now most
+        other browsers enable it too. Given the old reasons no longer apply,
+        the BCI has now been enabled in order to get better text rendering when
+        embedded hints are available.
+
+        * platform/graphics/freetype/FontCustomPlatformDataFreeType.cpp:
+        (WebCore::FontCustomPlatformData::FontCustomPlatformData):
+
 2017-07-12  Commit Queue  <commit-queue@webkit.org>
 

trunk/Source/WebCore/platform/graphics/freetype/FontCustomPlatformDataFreeType.cpp

@@ -36 +36 @@
 
 FontCustomPlatformData::FontCustomPlatformData(FT_Face freeTypeFace, SharedBuffer& buffer)
-    : m_fontFace(cairo_ft_font_face_create_for_ft_face(freeTypeFace, FT_LOAD_FORCE_AUTOHINT))
+    : m_fontFace(cairo_ft_font_face_create_for_ft_face(freeTypeFace, FT_LOAD_DEFAULT))
 {
-    // FT_LOAD_FORCE_AUTOHINT prohibits use of the font's native hinting. This
-    // is a safe option for custom fonts because (a) some such fonts may have
-    // broken hinting, which site admins may not notice if other browsers do not
-    // use the native hints, and (b) allowing native hints exposes the FreeType
-    // bytecode interpreter to potentially-malicious input. Treating web fonts
-    // differently than system fonts is non-ideal, but the result of autohinting
-    // is always decent, whereas native hints sometimes look terrible, and
-    // unlike system fonts where Fontconfig may change the hinting settings on a
-    // per-font basis, the same settings are used for all web fonts. Note that
-    // Chrome is considering switching from autohinting to native hinting in
-    // https://code.google.com/p/chromium/issues/detail?id=173207 but this is
-    // more risk than we want to assume for now. See
-    // https://bugs.webkit.org/show_bug.cgi?id=140994 before changing this, and
-    // also consider that (a) the fonts' native hints will all be designed to
-    // work on Windows, and might not look good at all with FreeType, whereas
-    // automatic hints will always look decent, and (b) Fontconfig is not
-    // capable of providing any per-font hinting settings for web fonts, unlike
-    // for system fonts, so it seems acceptable to treat them differently.
-
     buffer.ref(); // This is balanced by the buffer->deref() in releaseCustomFontData.
     static cairo_user_data_key_t bufferKey;