win: Hack around Gill Sans Ultra Bold DirectWrite problem

content/common/dwrite_font_platform_win.cc

 // 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 "content/public/common/dwrite_font_platform_win.h"
 
 #include <dwrite.h>
 #include <map>
 #include <string>
 #include <utility>
@@ skipping 66 matching lines @@
 // users, so we are putting arbitrary limit on cache file size. There are
 // multiple ways we can tune our working size, like mapping only required part
 // of section at any given time.
 const double kArbitraryCacheFileSizeLimit = (30 * 1024 * 1024);
 
 // We have chosen current font file length arbitrarily. In our logic
 // if we don't find file we are looking for in cache we end up loading
 // that file directly from system fonts folder.
 const unsigned int kMaxFontFileNameLength = 34;
 
-const DWORD kCacheFileVersion = 103;
+const DWORD kCacheFileVersion = 104;

[scottmg, 2015/02/06 19:27:33]

shrikant: Is this necessary?

[Shrikant Kelkar, 2015/02/06 20:56:22]

Not necessary in this case.. Registry fonts will be loaded irrespective of
presence in cache, but if you want to force remove from cache then you need this
and then please modify font format file in unit test as well.

[scottmg, 2015/02/06 21:39:33]

OK, undid this change.

 const DWORD kFileSignature = 0x4D4F5243; // CROM
 const DWORD kMagicCompletionSignature = 0x454E4F44; // DONE
 
 const DWORD kUndefinedDWORDS = 36;
 
 // Make sure that all structure sizes align with 8 byte boundary otherwise
 // dr. memory test may complain.
 #pragma pack(push, 8)
 // Cache file header, includes signature, completion bits and version.
 struct CacheFileHeader {
@@ skipping 668 matching lines @@
         regkey.ReadValue(name.c_str(), &value) == ERROR_SUCCESS) {
       base::FilePath path(value.c_str());
       // We need to check if file name is the only component that exists,
       // we will ignore all other registry entries.
       std::vector<base::FilePath::StringType> components;
       path.GetComponents(&components);
       if ((components.size() == 1 &&
            value.size() < kMaxFontFileNameLength - 1) ||
           base::FilePath::CompareEqualIgnoreCase(system_font_path.value(),
                                                  path.DirName().value())) {
-        reg_fonts_.push_back(value.c_str());
+        // "Gill Sans Ultra Bold" turns into an Ultra Bold weight "Gill Sans"
+        // in DirectWrite, but most users don't have any other weights. The
+        // regular weight font is named "Gill Sans MT", but that ends up in a
+        // different family with that name. On Mac, there's a "Gill Sans" with
+        // various weights, so CSS authors use { 'font-family': 'Gill Sans',
+        // 'Gill Sans MT', ... } and because of the DirectWrite family futzing,
+        // they end up with an Ultra Bold font, when they just wanted "Gill
+        // Sans". Mozilla implemented a more complicated hack where they
+        // effectively rename the Ultra Bold font to "Gill Sans MT Ultra Bold",
+        // but because the Ultra Bold font is so ugly anyway, we simply ignore
+        // it. See http://www.microsoft.com/typography/fonts/font.aspx?FMID=978
+        // for a picture of the font, and the file name. We also ignore "Gill
+        // Sans Ultra Bold Condensed".
+        if (!base::FilePath::CompareEqualIgnoreCase(
+                path.value(), FILE_PATH_LITERAL("gilsanub.ttf")) &&
+            !base::FilePath::CompareEqualIgnoreCase(
+                path.value(), FILE_PATH_LITERAL("gillubcd.ttf"))) {

[Shrikant Kelkar, 2015/02/06 20:56:22]

Since more than one, please consider using fonts_to_ignore list/vector/map?

[scottmg, 2015/02/06 21:39:33]

Done.

+          reg_fonts_.push_back(value.c_str());
+        }
       }
     }
   }
   UMA_HISTOGRAM_COUNTS("DirectWrite.Fonts.Loaded", reg_fonts_.size());
   UMA_HISTOGRAM_COUNTS("DirectWrite.Fonts.Ignored",
                        regkey.GetValueCount() - reg_fonts_.size());
   return true;
 }
 
 // This list is mainly based on prefs/prefs_tab_helper.cc kFontDefaults.
@@ skipping 390 matching lines @@
   g_shared_font_cache.Set(mapping);
 
   return true;
 }
 
 bool BuildFontCache(const base::FilePath& file) {
   return BuildFontCacheInternal(file.value().c_str());
 }
 
 }  // namespace content