Improve generation of glyph advance array.

Review URL: http://codereview.appspot.com/4830068

git-svn-id: http://skia.googlecode.com/svn/trunk@2126 2bbb7eff-a529-9590-31e7-b0007b416f81

include/core/SkAdvancedTypefaceMetrics.h

@@ -132,10 +132,21 @@ void finishRange(
         typename SkAdvancedTypefaceMetrics::AdvanceMetric<Data>::MetricType
                 type);
 
+/** Retrieve advance data for glyphs. Used by the PDF backend. It calls
+    underlying platform dependent API getAdvance to acquire the data.
+    @param num_glyphs    Total number of glyphs in the given font.
+    @param glyphIDs      For per-glyph info, specify subset of the font by
+                         giving glyph ids.  Each integer represents a glyph
+                         id.  Passing NULL means all glyphs in the font.
+    @param glyphIDsCount Number of elements in subsetGlyphIds. Ignored if
+                         glyphIDs is NULL.
+*/
 template <typename Data, typename FontHandle>
 SkAdvancedTypefaceMetrics::AdvanceMetric<Data>* getAdvanceData(
         FontHandle fontHandle,
         int num_glyphs,
+        const uint32_t* glyphIDs,
+        uint32_t glyphIDsCount,
         bool (*getAdvance)(FontHandle fontHandle, int gId, Data* data));
 
 } // namespace skia_advanced_typeface_metrics_utils

include/core/SkFontHost.h

@@ -181,10 +181,17 @@ public:
                             names, etc.) should be populated.
         @return The returned object has already been referenced.  NULL is
                 returned if the font is not found.
+        @param glyphIDs  For per-glyph info, specify subset of the font by
+                         giving glyph ids.  Each integer represents a glyph
+                         id.  Passing NULL means all glyphs in the font.
+        @param glyphIDsCount Number of elements in subsetGlyphIds. Ignored if
+                             glyphIDs is NULL.
      */
     static SkAdvancedTypefaceMetrics* GetAdvancedTypefaceMetrics(
             SkFontID fontID,
-            SkAdvancedTypefaceMetrics::PerGlyphInfo perGlyphInfo);
+            SkAdvancedTypefaceMetrics::PerGlyphInfo perGlyphInfo,
+            const uint32_t* glyphIDs,
+            uint32_t glyphIDsCount);
 
     /** Return the number of tables in the font
      */
@@ -293,4 +300,3 @@ public:
 };
 
 #endif
-

include/core/SkTypeface.h

@@ -134,10 +134,17 @@ public:
     /** Retrieve detailed typeface metrics.  Used by the PDF backend.
         @param perGlyphInfo Indicate what glyph specific information (advances,
                             names, etc.) should be populated.
+        @param glyphIDs  For per-glyph info, specify subset of the font by
+                         giving glyph ids.  Each integer represents a glyph
+                         id.  Passing NULL means all glyphs in the font.
+        @param glyphIDsCount Number of elements in subsetGlyphIds. Ignored if
+                             glyphIDs is NULL.
         @return The returned object has already been referenced.
      */
     SkAdvancedTypefaceMetrics* getAdvancedTypefaceMetrics(
-            SkAdvancedTypefaceMetrics::PerGlyphInfo perGlyphInfo) const;
+            SkAdvancedTypefaceMetrics::PerGlyphInfo perGlyphInfo,
+            const uint32_t* glyphIDs = NULL,
+            uint32_t glyphIDsCount = 0) const;
 
 protected:
     /** uniqueID must be unique (please!) and non-zero

include/core/SkTypes.h

@@ -478,4 +478,3 @@ private:
 #endif /* C++ */
 
 #endif
-

include/pdf/SkPDFFont.h

@@ -137,6 +137,7 @@ protected:
 
     // Accessors for subclass.
     SkAdvancedTypefaceMetrics* fontInfo();
+    void setFontInfo(SkAdvancedTypefaceMetrics* info);
     uint16_t firstGlyphID() const;
     uint16_t lastGlyphID() const;
     void setLastGlyphID(uint16_t glyphID);

src/core/SkAdvancedTypefaceMetrics.cpp

@@ -65,6 +65,8 @@ template <typename Data, typename FontHandle>
 SkAdvancedTypefaceMetrics::AdvanceMetric<Data>* getAdvanceData(
         FontHandle fontHandle,
         int num_glyphs,
+        const uint32_t* subsetGlyphIDs,
+        uint32_t subsetGlyphIDsLength,
         bool (*getAdvance)(FontHandle fontHandle, int gId, Data* data)) {
     // Assuming that an ASCII representation of a width or a glyph id is,
     // on average, 3 characters long gives the following cut offs for
@@ -82,10 +84,17 @@ SkAdvancedTypefaceMetrics::AdvanceMetric<Data>* getAdvanceData(
     curRange = appendRange(&result, 0);
     Data lastAdvance = SK_MinS16;
     int repeats = 0;
+    uint32_t subsetIndex = 0;
     for (int gId = 0; gId <= num_glyphs; gId++) {
-        Data advance;
+        Data advance = 0;
         if (gId < num_glyphs) {
+            // Get glyph id only when subset is NULL, or the id is in subset.
+            if (!subsetGlyphIDs ||
+                (subsetIndex < subsetGlyphIDsLength &&
+                static_cast<uint32_t>(gId) == subsetGlyphIDs[subsetIndex])) {
                 SkAssertResult(getAdvance(fontHandle, gId, &advance));
+                ++subsetIndex;
+            }
         } else {
             advance = SK_MinS16;
         }
@@ -139,16 +148,22 @@ SkAdvancedTypefaceMetrics::AdvanceMetric<Data>* getAdvanceData(
 template SkAdvancedTypefaceMetrics::WidthRange* getAdvanceData(
         HDC hdc,
         int num_glyphs,
+        const uint32_t* subsetGlyphIDs,
+        uint32_t subsetGlyphIDsLength,
         bool (*getAdvance)(HDC hdc, int gId, int16_t* data));
 #elif defined(SK_BUILD_FOR_UNIX)
 template SkAdvancedTypefaceMetrics::WidthRange* getAdvanceData(
         FT_Face face,
         int num_glyphs,
+        const uint32_t* subsetGlyphIDs,
+        uint32_t subsetGlyphIDsLength,
         bool (*getAdvance)(FT_Face face, int gId, int16_t* data));
 #elif defined(SK_BUILD_FOR_MAC) || defined(SK_BUILD_FOR_IOS)
 template SkAdvancedTypefaceMetrics::WidthRange* getAdvanceData(
         CTFontRef ctFont,
         int num_glyphs,
+        const uint32_t* subsetGlyphIDs,
+        uint32_t subsetGlyphIDsLength,
         bool (*getAdvance)(CTFontRef ctFont, int gId, int16_t* data));
 #endif
 template void resetRange(

src/core/SkTypeface.cpp

@@ -93,6 +93,11 @@ SkTypeface* SkTypeface::Deserialize(SkStream* stream) {
 }
 
 SkAdvancedTypefaceMetrics* SkTypeface::getAdvancedTypefaceMetrics(
-        SkAdvancedTypefaceMetrics::PerGlyphInfo perGlyphInfo) const {
+        SkAdvancedTypefaceMetrics::PerGlyphInfo perGlyphInfo,
-    return SkFontHost::GetAdvancedTypefaceMetrics(fUniqueID, perGlyphInfo);
+        const uint32_t* glyphIDs,
+        uint32_t glyphIDsCount) const {
+    return SkFontHost::GetAdvancedTypefaceMetrics(fUniqueID,
+                                                  perGlyphInfo,
+                                                  glyphIDs,
+                                                  glyphIDsCount);
 }

src/pdf/SkPDFFont.cpp

@@ -528,7 +528,7 @@ static void sk_delete_array(const void* ptr, size_t, void*) {
 
 static int get_subset_font_stream(const char* fontName,
                                   const SkTypeface* typeface,
-                                  const SkPDFGlyphSet* subset,
+                                  const SkTDArray<uint32_t>& subset,
                                   SkPDFStream** fontStream) {
     SkRefPtr<SkStream> fontData =
             SkFontHost::OpenStream(SkTypeface::UniqueID(typeface));
@@ -537,11 +537,6 @@ static int get_subset_font_stream(const char* fontName,
     int fontSize = fontData->getLength();
 
 #if defined (SK_SFNTLY_SUBSETTER)
-    // Generate glyph id array.
-    SkTDArray<uint32_t> glyphIDs;
-    glyphIDs.push(0);  // Always include glyph 0.
-    subset->exportTo(&glyphIDs);
-
     // Read font into buffer.
     SkPDFStream* subsetFontStream = NULL;
     SkTDArray<unsigned char> originalFont;
@@ -555,8 +550,8 @@ static int get_subset_font_stream(const char* fontName,
         int subsetFontSize = SfntlyWrapper::SubsetFont(fontName,
                                                        originalFont.begin(),
                                                        fontSize,
-                                                       glyphIDs.begin(),
+                                                       subset.begin(),
-                                                       glyphIDs.count(),
+                                                       subset.count(),
                                                        &subsetFont);
         if (subsetFontSize > 0 && subsetFont != NULL) {
             SkAutoDataUnref data(SkData::NewWithProc(subsetFont,
@@ -751,13 +746,26 @@ SkPDFFont* SkPDFFont::GetFontResource(SkTypeface* typeface, uint16_t glyphID) {
         relatedFontDescriptor = relatedFont->getFontDescriptor();
     } else {
         SkAdvancedTypefaceMetrics::PerGlyphInfo info;
-        info = SkAdvancedTypefaceMetrics::kHAdvance_PerGlyphInfo;
+        info = SkAdvancedTypefaceMetrics::kGlyphNames_PerGlyphInfo;
-        info = SkTBitOr<SkAdvancedTypefaceMetrics::PerGlyphInfo>(
-                  info, SkAdvancedTypefaceMetrics::kGlyphNames_PerGlyphInfo);
         info = SkTBitOr<SkAdvancedTypefaceMetrics::PerGlyphInfo>(
                   info, SkAdvancedTypefaceMetrics::kToUnicode_PerGlyphInfo);
-        fontMetrics = SkFontHost::GetAdvancedTypefaceMetrics(fontID, info);
+#if !defined (SK_SFNTLY_SUBSETTER)
+        info = SkTBitOr<SkAdvancedTypefaceMetrics::PerGlyphInfo>(
+                  info, SkAdvancedTypefaceMetrics::kHAdvance_PerGlyphInfo);
+#endif
+        fontMetrics =
+            SkFontHost::GetAdvancedTypefaceMetrics(fontID, info, NULL, 0);
+#if defined (SK_SFNTLY_SUBSETTER)
         SkSafeUnref(fontMetrics.get());  // SkRefPtr and Get both took a ref.
+        if (fontMetrics->fType != SkAdvancedTypefaceMetrics::kTrueType_Font) {
+            // Font does not support subsetting, get new info with advance.
+            info = SkTBitOr<SkAdvancedTypefaceMetrics::PerGlyphInfo>(
+                      info, SkAdvancedTypefaceMetrics::kHAdvance_PerGlyphInfo);
+            fontMetrics =
+                SkFontHost::GetAdvancedTypefaceMetrics(fontID, info, NULL, 0);
+            SkSafeUnref(fontMetrics.get());  // SkRefPtr and Get both took a ref
+        }
+#endif
     }
 
     SkPDFFont* font = Create(fontMetrics.get(), typeface, glyphID,
@@ -850,6 +858,13 @@ SkAdvancedTypefaceMetrics* SkPDFFont::fontInfo() {
     return fFontInfo.get();
 }
 
+void SkPDFFont::setFontInfo(SkAdvancedTypefaceMetrics* info) {
+    if (info == NULL || info == fFontInfo.get()) {
+        return;
+    }
+    fFontInfo = info;
+}
+
 uint16_t SkPDFFont::firstGlyphID() const {
     return fFirstGlyphID;
 }
@@ -978,9 +993,10 @@ bool SkPDFType0Font::populate(const SkPDFGlyphSet* subset) {
     insertName("BaseFont", fontInfo()->fFontName);
     insertName("Encoding", "Identity-H");
 
+    SkPDFCIDFont* newCIDFont;
+    newCIDFont = new SkPDFCIDFont(fontInfo(), typeface(), subset);
+
     // Pass ref new created to fResources.
-    SkPDFCIDFont* newCIDFont =
-        new SkPDFCIDFont(fontInfo(), typeface(), subset);
     addResource(newCIDFont);
     SkRefPtr<SkPDFArray> descendantFonts = new SkPDFArray();
     descendantFonts->unref();  // SkRefPtr and new took a reference.
@@ -1006,18 +1022,19 @@ SkPDFCIDFont::SkPDFCIDFont(SkAdvancedTypefaceMetrics* info,
 SkPDFCIDFont::~SkPDFCIDFont() {}
 
 bool SkPDFCIDFont::addFontDescriptor(int16_t defaultWidth,
-                                     const SkPDFGlyphSet* subset) {
+                                     const SkTDArray<uint32_t>* subset) {
     SkRefPtr<SkPDFDict> descriptor = new SkPDFDict("FontDescriptor");
     descriptor->unref();  // SkRefPtr and new both took a ref.
     setFontDescriptor(descriptor.get());
 
     switch (getType()) {
         case SkAdvancedTypefaceMetrics::kTrueType_Font: {
+            SkASSERT(subset);
             // Font subsetting
             SkPDFStream* rawStream = NULL;
             int fontSize = get_subset_font_stream(fontInfo()->fFontName.c_str(),
                                                   typeface(),
-                                                  subset,
+                                                  *subset,
                                                   &rawStream);
             SkASSERT(fontSize);
             SkASSERT(rawStream);
@@ -1060,6 +1077,35 @@ bool SkPDFCIDFont::addFontDescriptor(int16_t defaultWidth,
 }
 
 bool SkPDFCIDFont::populate(const SkPDFGlyphSet* subset) {
+    // Generate new font metrics with advance info for true type fonts.
+    if (fontInfo()->fType == SkAdvancedTypefaceMetrics::kTrueType_Font) {
+        // Generate glyph id array.
+        SkTDArray<uint32_t> glyphIDs;
+        glyphIDs.push(0);  // Always include glyph 0.
+        if (subset) {
+            subset->exportTo(&glyphIDs);
+        }
+
+        SkRefPtr<SkAdvancedTypefaceMetrics> fontMetrics;
+        SkAdvancedTypefaceMetrics::PerGlyphInfo info;
+        info = SkAdvancedTypefaceMetrics::kGlyphNames_PerGlyphInfo;
+        info = SkTBitOr<SkAdvancedTypefaceMetrics::PerGlyphInfo>(
+                  info, SkAdvancedTypefaceMetrics::kHAdvance_PerGlyphInfo);
+        uint32_t* glyphs = (glyphIDs.count() == 1) ? NULL : glyphIDs.begin();
+        uint32_t glyphsCount = glyphs ? glyphIDs.count() : 0;
+        fontMetrics =
+            SkFontHost::GetAdvancedTypefaceMetrics(typeface()->uniqueID(),
+                                                   info,
+                                                   glyphs,
+                                                   glyphsCount);
+        SkSafeUnref(fontMetrics.get());  // SkRefPtr and Get both took a ref
+        setFontInfo(fontMetrics.get());
+        addFontDescriptor(0, &glyphIDs);
+    } else {
+        // Other CID fonts
+        addFontDescriptor(0, NULL);
+    }
+
     insertName("BaseFont", fontInfo()->fFontName);
 
     if (getType() == SkAdvancedTypefaceMetrics::kType1CID_Font) {
@@ -1078,8 +1124,6 @@ bool SkPDFCIDFont::populate(const SkPDFGlyphSet* subset) {
     sysInfo->insertInt("Supplement", 0);
     insert("CIDSystemInfo", sysInfo.get());
 
-    addFontDescriptor(0, subset);
-
     if (fontInfo()->fGlyphWidths.get()) {
         int16_t defaultWidth = 0;
         SkRefPtr<SkPDFArray> widths =

src/pdf/SkPDFFontImpl.h

@@ -46,7 +46,8 @@ private:
                  const SkPDFGlyphSet* subset);
 
     bool populate(const SkPDFGlyphSet* subset);
-    bool addFontDescriptor(int16_t defaultWidth, const SkPDFGlyphSet* subset);
+    bool addFontDescriptor(int16_t defaultWidth,
+                           const SkTDArray<uint32_t>* subset);
 };
 
 class SkPDFType1Font : public SkPDFFont {

src/ports/SkFontHost_FreeType.cpp

@@ -408,7 +408,9 @@ static void populate_glyph_to_unicode(FT_Face& face,
 // static
 SkAdvancedTypefaceMetrics* SkFontHost::GetAdvancedTypefaceMetrics(
         uint32_t fontID,
-        SkAdvancedTypefaceMetrics::PerGlyphInfo perGlyphInfo) {
+        SkAdvancedTypefaceMetrics::PerGlyphInfo perGlyphInfo,
+        const uint32_t* glyphIDs,
+        uint32_t glyphIDsCount) {
 #if defined(SK_BUILD_FOR_MAC) || defined(ANDROID)
     return NULL;
 #else
@@ -552,7 +554,11 @@ SkAdvancedTypefaceMetrics* SkFontHost::GetAdvancedTypefaceMetrics(
                         SkAdvancedTypefaceMetrics::WidthRange::kRange);
         } else {
             info->fGlyphWidths.reset(
-                getAdvanceData(face, face->num_glyphs, &getWidthAdvance));
+                getAdvanceData(face,
+                               face->num_glyphs,
+                               glyphIDs,
+                               glyphIDsCount,
+                               &getWidthAdvance));
         }
     }
 
@@ -588,6 +594,7 @@ SkAdvancedTypefaceMetrics* SkFontHost::GetAdvancedTypefaceMetrics(
     return info;
 #endif
 }
+
 ///////////////////////////////////////////////////////////////////////////
 
 static bool bothZero(SkScalar a, SkScalar b) {

src/ports/SkFontHost_mac_atsui.cpp

@@ -476,7 +476,9 @@ SkTypeface* SkFontHost::CreateTypefaceFromFile(const char path[]) {
 // static
 SkAdvancedTypefaceMetrics* SkFontHost::GetAdvancedTypefaceMetrics(
         uint32_t fontID,
-        SkAdvancedTypefaceMetrics::PerGlyphInfo perGlyphInfo) {
+        SkAdvancedTypefaceMetrics::PerGlyphInfo perGlyphInfo,
+        const uint32_t* glyphIDs,
+        uint32_t glyphIDsCount) {
     SkASSERT(!"SkFontHost::GetAdvancedTypefaceMetrics unimplemented");
     return NULL;
 }
@@ -609,4 +611,3 @@ size_t SkFontHost::GetTableData(SkFontID fontID, SkFontTableTag tag,
     }
     return length;
 }
-

src/ports/SkFontHost_mac_coretext.cpp

@@ -761,7 +761,9 @@ static bool getWidthAdvance(CTFontRef ctFont, int gId, int16_t* data) {
 // static
 SkAdvancedTypefaceMetrics* SkFontHost::GetAdvancedTypefaceMetrics(
         uint32_t fontID,
-        SkAdvancedTypefaceMetrics::PerGlyphInfo perGlyphInfo) {
+        SkAdvancedTypefaceMetrics::PerGlyphInfo perGlyphInfo,
+        const uint32_t* glyphIDs,
+        uint32_t glyphIDsCount) {
     CTFontRef ctFont = GetFontRefFromFontID(fontID);
     ctFont = CTFontCreateCopyWithAttributes(ctFont, CTFontGetUnitsPerEm(ctFont),
                                             NULL, NULL);
@@ -847,7 +849,11 @@ SkAdvancedTypefaceMetrics* SkFontHost::GetAdvancedTypefaceMetrics(
                         SkAdvancedTypefaceMetrics::WidthRange::kDefault);
         } else {
             info->fGlyphWidths.reset(
-                getAdvanceData(ctFont, glyphCount, &getWidthAdvance));
+                getAdvanceData(ctFont,
+                               glyphCount,
+                               glyphIDs,
+                               glyphIDsCount,
+                               &getWidthAdvance));
         }
     }
 
@@ -1115,7 +1121,3 @@ size_t SkFontHost::GetTableData(SkFontID fontID, SkFontTableTag tag,
     memcpy(data, CFDataGetBytePtr(cfData) + offset, length);
     return(length);
 }
-
-
-
-

src/ports/SkFontHost_win.cpp

@@ -743,7 +743,9 @@ static bool getWidthAdvance(HDC hdc, int gId, int16_t* advance) {
 // static
 SkAdvancedTypefaceMetrics* SkFontHost::GetAdvancedTypefaceMetrics(
         uint32_t fontID,
-        SkAdvancedTypefaceMetrics::PerGlyphInfo perGlyphInfo) {
+        SkAdvancedTypefaceMetrics::PerGlyphInfo perGlyphInfo,
+        const uint32_t* glyphIDs,
+        uint32_t glyphIDsCount) {
     LOGFONT lf;
     GetLogFontByID(fontID, &lf);
     SkAdvancedTypefaceMetrics* info = NULL;
@@ -863,7 +865,11 @@ SkAdvancedTypefaceMetrics* SkFontHost::GetAdvancedTypefaceMetrics(
                         SkAdvancedTypefaceMetrics::WidthRange::kDefault);
         } else {
             info->fGlyphWidths.reset(
-                getAdvanceData(hdc, glyphCount, &getWidthAdvance));
+                getAdvanceData(hdc,
+                               glyphCount,
+                               glyphIDs,
+                               glyphIDsCount,
+                               &getWidthAdvance));
         }
     }