SkAdvancedTypefaceMetrics: factor out GlyphToUnicode

Change-Id: Iedce8c1ea2c405d5ab64ccac353970d5cd2b9d63
Reviewed-on: https://skia-review.googlesource.com/126507
Commit-Queue: Hal Canary <halcanary@google.com>
Reviewed-by: Ben Wagner <bungeman@google.com>

1 files changed, 22 insertions, 8 deletions

diff --git a/src/ports/SkFontHost_win.cpp b/src/ports/SkFontHost_win.cpp
index 35a0a74b22..f1da8053f2 100644
--- a/src/ports/SkFontHost_win.cpp
+++ b/src/ports/SkFontHost_win.cpp
@@ -261,6 +261,7 @@ protected:
     SkScalerContext* onCreateScalerContext(const SkScalerContextEffects&,
                                            const SkDescriptor*) const override;
     void onFilterRec(SkScalerContextRec*) const override;
+    void getGlyphToUnicodeMap(SkUnichar*) const override;
     std::unique_ptr<SkAdvancedTypefaceMetrics> onGetAdvancedMetrics() const override;
     void onGetFontDescriptor(SkFontDescriptor*, bool*) const override;
     int onCharsToGlyphs(const void* chars, Encoding encoding,
@@ -362,7 +363,8 @@ void SkLOGFONTFromTypeface(const SkTypeface* face, LOGFONT* lf) {
 // require parsing the TTF cmap table (platform 4, encoding 12) directly instead
 // of calling GetFontUnicodeRange().
 static void populate_glyph_to_unicode(HDC fontHdc, const unsigned glyphCount,
-                                      SkTDArray<SkUnichar>* glyphToUnicode) {
+                                      SkUnichar* glyphToUnicode) {
+    sk_bzero(glyphToUnicode, sizeof(SkUnichar) * glyphCount);
     DWORD glyphSetBufferSize = GetFontUnicodeRanges(fontHdc, nullptr);
     if (!glyphSetBufferSize) {
         return;
@@ -375,8 +377,6 @@ static void populate_glyph_to_unicode(HDC fontHdc, const unsigned glyphCount,
         return;
     }
 
-    glyphToUnicode->setCount(glyphCount);
-    memset(glyphToUnicode->begin(), 0, glyphCount * sizeof(SkUnichar));
     for (DWORD i = 0; i < glyphSet->cRanges; ++i) {
         // There is no guarantee that within a Unicode range, the corresponding
         // glyph id in a font file are continuous. So, even if we have ranges,
@@ -399,9 +399,8 @@ static void populate_glyph_to_unicode(HDC fontHdc, const unsigned glyphCount,
         // unlikely to have collisions since glyph reuse happens mostly for
         // different Unicode pages.
         for (USHORT j = 0; j < count; ++j) {
-            if (glyph[j] != 0xffff && glyph[j] < glyphCount &&
-                (*glyphToUnicode)[glyph[j]] == 0) {
-                (*glyphToUnicode)[glyph[j]] = chars[j];
+            if (glyph[j] != 0xFFFF && glyph[j] < glyphCount && glyphToUnicode[glyph[j]] == 0) {
+                glyphToUnicode[glyph[j]] = chars[j];
             }
         }
     }
@@ -1707,6 +1706,23 @@ void LogFontTypeface::onGetFontDescriptor(SkFontDescriptor* desc,
     *isLocalStream = this->fSerializeAsStream;
 }
 
+void LogFontTypeface::getGlyphToUnicodeMap(SkUnichar* dstArray) const {
+    HDC hdc = ::CreateCompatibleDC(nullptr);
+    HFONT font = CreateFontIndirect(&fLogFont);
+    HFONT savefont = (HFONT)SelectObject(hdc, font);
+    LOGFONT lf = fLogFont;
+    HFONT designFont = CreateFontIndirect(&lf);
+    SelectObject(hdc, designFont);
+
+    unsigned int glyphCount = calculateGlyphCount(hdc, fLogFont);
+    populate_glyph_to_unicode(hdc, glyphCount, dstArray);
+
+    SelectObject(hdc, savefont);
+    DeleteObject(designFont);
+    DeleteObject(font);
+    DeleteDC(hdc);
+}
+
 std::unique_ptr<SkAdvancedTypefaceMetrics> LogFontTypeface::onGetAdvancedMetrics() const {
     LOGFONT lf = fLogFont;
     std::unique_ptr<SkAdvancedTypefaceMetrics> info(nullptr);
@@ -1757,8 +1773,6 @@ std::unique_ptr<SkAdvancedTypefaceMetrics> LogFontTypeface::onGetAdvancedMetrics
         }
     }
 
-    populate_glyph_to_unicode(hdc, glyphCount, &(info->fGlyphToUnicode));
-
     if (glyphCount > 0 &&
         (otm.otmTextMetrics.tmPitchAndFamily & TMPF_TRUETYPE)) {
         info->fType = SkAdvancedTypefaceMetrics::kTrueType_Font;