Changeset 30179 in webkit

Timestamp:

Feb 12, 2008, 3:54:39 PM (17 years ago)

Author:

mitz@apple.com

Message:

Reviewed by Adam Roben.

• fix ​http://bugs.webkit.org/show_bug.cgi?id=17041 <rdar://problem/5709660> Eastern Asian fonts do not display without specific box in Control Panel

Revised the system fallback font lookup logic to use MLang font linking
again. To avoid reintroducing bug 16548 and <rdar://problem/5280188>,
for CJK characters, try linking based on a single code page at a time,
starting with the user's default code page (if it is one of the CJK
code pages) followed by the other CJK code pages in a prescribed order
that matches what Firefox does.

• platform/graphics/win/FontCacheWin.cpp: (WebCore::getCJKCodePageMasks): Added. Returns the search order for CJK code pages, with the user's default code page first. (WebCore::currentFontContainsCharacter): Factored out of getFontDataForCharacters(). (WebCore::createMLangFont): Ditto. (WebCore::FontCache::getFontDataForCharacters):

Location:

trunk/WebCore

Files:

• ChangeLog (modified) (1 diff)
• platform/graphics/win/FontCacheWin.cpp (modified) (4 diffs)

trunk/WebCore/ChangeLog

@@ +1 @@
+2008-02-12  Dan Bernstein  <mitz@apple.com>
+
+        Reviewed by Adam Roben.
+
+        - fix http://bugs.webkit.org/show_bug.cgi?id=17041
+          <rdar://problem/5709660> Eastern Asian fonts do not display without specific box in Control Panel
+
+        Revised the system fallback font lookup logic to use MLang font linking
+        again. To avoid reintroducing bug 16548 and <rdar://problem/5280188>,
+        for CJK characters, try linking based on a single code page at a time,
+        starting with the user's default code page (if it is one of the CJK
+        code pages) followed by the other CJK code pages in a prescribed order
+        that matches what Firefox does.
+
+        * platform/graphics/win/FontCacheWin.cpp:
+        (WebCore::getCJKCodePageMasks): Added. Returns the search order for CJK
+        code pages, with the user's default code page first.
+        (WebCore::currentFontContainsCharacter): Factored out of
+        getFontDataForCharacters().
+        (WebCore::createMLangFont): Ditto.
+        (WebCore::FontCache::getFontDataForCharacters):
+
 2008-02-12  Rodney Dawes  <dobey@wayofthemonkey.com>
 

trunk/WebCore/platform/graphics/win/FontCacheWin.cpp

@@ -33 +33 @@
 #include "SimpleFontData.h"
 #include "StringHash.h"
+#include "UnicodeRange.h"
 #include <windows.h>
 #include <mlang.h>
@@ -115 +116 @@
 }
 
+static const Vector<DWORD, 4>& getCJKCodePageMasks()
+{
+    // The default order in which we look for a font for a CJK character. If the user's default code page is
+    // one of these, we will use it first.
+    static const UINT CJKCodePages[] = { 
+        932, /* Japanese */
+        936, /* Simplified Chinese */
+        950, /* Traditional Chinese */
+        949  /* Korean */
+    };
+
+    static Vector<DWORD, 4> codePageMasks;
+    static bool initialized;
+    if (!initialized) {
+        initialized = true;
+        IMLangFontLink2* langFontLink = FontCache::getFontLinkInterface();
+        if (!langFontLink)
+            return codePageMasks;
+
+        UINT defaultCodePage;
+        DWORD defaultCodePageMask = 0;
+        if (GetLocaleInfo(LOCALE_USER_DEFAULT, LOCALE_RETURN_NUMBER | LOCALE_IDEFAULTANSICODEPAGE, reinterpret_cast<LPWSTR>(&defaultCodePage), sizeof(defaultCodePage)))
+            langFontLink->CodePageToCodePages(defaultCodePage, &defaultCodePageMask);
+
+        if (defaultCodePage == CJKCodePages[0] || defaultCodePage == CJKCodePages[1] || defaultCodePage == CJKCodePages[2] || defaultCodePage == CJKCodePages[3])
+            codePageMasks.append(defaultCodePageMask);
+        for (unsigned i = 0; i < 4; ++i) {
+            if (defaultCodePage != CJKCodePages[i]) {
+                DWORD codePageMask;
+                langFontLink->CodePageToCodePages(CJKCodePages[i], &codePageMask);
+                codePageMasks.append(codePageMask);
+            }
+        }
+    }
+    return codePageMasks;
+}
+
+static bool currentFontContainsCharacter(HDC hdc, UChar character)
+{
+    static Vector<char, 512> glyphsetBuffer;
+    glyphsetBuffer.resize(GetFontUnicodeRanges(hdc, 0));
+    GLYPHSET* glyphset = reinterpret_cast<GLYPHSET*>(glyphsetBuffer.data());
+    GetFontUnicodeRanges(hdc, glyphset);
+
+    // FIXME: Change this to a binary search.
+    unsigned i = 0;
+    while (i < glyphset->cRanges && glyphset->ranges[i].wcLow <= character)
+        i++;
+
+    return i && glyphset->ranges[i - 1].wcLow + glyphset->ranges[i - 1].cGlyphs > character;
+}
+
+static HFONT createMLangFont(IMLangFontLink2* langFontLink, HDC hdc, DWORD codePageMask, UChar character = 0)
+{
+    HFONT MLangFont;
+    HFONT hfont = 0;
+    if (SUCCEEDED(langFontLink->MapFont(hdc, codePageMask, character, &MLangFont)) && MLangFont) {
+        LOGFONT lf;
+        GetObject(MLangFont, sizeof(LOGFONT), &lf);
+        langFontLink->ReleaseFont(MLangFont);
+        hfont = CreateFontIndirect(&lf);
+    }
+    return hfont;
+}
+
 const SimpleFontData* FontCache::getFontDataForCharacters(const Font& font, const UChar* characters, int length)
 {
+    UChar character = characters[0];
     SimpleFontData* fontData = 0;
     HDC hdc = GetDC(0);
-    HFONT primaryFont = font.primaryFont()->fontDataForCharacter(characters[0])->m_font.hfont();
+    HFONT primaryFont = font.primaryFont()->fontDataForCharacter(character)->platformData().hfont();
     HGDIOBJ oldFont = SelectObject(hdc, primaryFont);
     HFONT hfont = 0;
 
-    // Special-case characters in the range U+2000..U+200F (spaces, zero width joiner and non-joiner,
-    // right to left and left to right marks). Uniscribe does not tell us what font it will use for these
-    // (presumably because it never renders their glyphs), so we use MapFont to find a font that contains
-    // them.
-    if (characters[0] >= 0x2000 && characters[0] <= 0x200F) {
-        IMLangFontLink2* langFontLink = getFontLinkInterface();
-        if (langFontLink) {
-            HFONT mLangFont;
-            langFontLink->MapFont(hdc, 0, characters[0], &mLangFont);
-            LOGFONT lf;
-            GetObject(mLangFont, sizeof(LOGFONT), &lf);
-            langFontLink->ReleaseFont(mLangFont);
-            hfont = CreateFontIndirect(&lf);
-        }
-    } else {
+    if (IMLangFontLink2* langFontLink = getFontLinkInterface()) {
+        // Try MLang font linking first.
+        DWORD codePages = 0;
+        langFontLink->GetCharCodePages(character, &codePages);
+
+        if (codePages && findCharUnicodeRange(character) == cRangeSetCJK) {
+            // The CJK character may belong to multiple code pages. We want to
+            // do font linking against a single one of them, preferring the default
+            // code page for the user's locale.
+            const Vector<DWORD, 4>& CJKCodePageMasks = getCJKCodePageMasks();
+            unsigned numCodePages = CJKCodePageMasks.size();
+            for (unsigned i = 0; i < numCodePages && !hfont; ++i) {
+                hfont = createMLangFont(langFontLink, hdc, CJKCodePageMasks[i]);
+                if (hfont && !(codePages & CJKCodePageMasks[i])) {
+                    // We asked about a code page that is not one of the code pages
+                    // returned by MLang, so the font might not contain the character.
+                    SelectObject(hdc, hfont);
+                    if (!currentFontContainsCharacter(hdc, character)) {
+                        DeleteObject(hfont);
+                        hfont = 0;
+                    }
+                    SelectObject(hdc, primaryFont);
+                }
+            }
+        } else
+            hfont = createMLangFont(langFontLink, hdc, codePages, character);
+    }
+
+    // A font returned from MLang is trusted to contain the character.
+    bool containsCharacter = hfont;
+
+    if (!hfont) {
         // To find out what font Uniscribe would use, we make it draw into a metafile and intercept
         // calls to CreateFontIndirect().
@@ -172 +256 @@
         GetTextFace(hdc, LF_FACESIZE, name);
         familyName = name;
-        // Check if the font contains the desired character.
-        static Vector<char, 512> glyphsetBuffer;
-        glyphsetBuffer.resize(GetFontUnicodeRanges(hdc, NULL));
-        GLYPHSET* glyphset = reinterpret_cast<GLYPHSET*>(glyphsetBuffer.data());
-        GetFontUnicodeRanges(hdc, glyphset);
-        // FIXME: Change this to a binary search.
-        unsigned i = 0;
-        while (i < glyphset->cRanges && glyphset->ranges[i].wcLow <= characters[0])
-            i++;
-        if (i && glyphset->ranges[i - 1].wcLow + glyphset->ranges[i - 1].cGlyphs > characters[0])
+
+        if (containsCharacter || currentFontContainsCharacter(hdc, character))
             break;
 
@@ -200 +276 @@
         linkedFontIndex++;
     }
-    
+
     if (hfont) {
         if (!familyName.isEmpty()) {