Don't try to scale embedded bitmaps.

src/ports/SkFontHost_FreeType.cpp

 
 /*
  * Copyright 2006 The Android Open Source Project
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "SkAdvancedTypefaceMetrics.h"
 #include "SkBitmap.h"
@@ skipping 1283 matching lines @@
             glyph->fAdvanceX = SkFDot6ToFixed(fFace->glyph->advance.x);
             glyph->fAdvanceY = -SkFDot6ToFixed(fFace->glyph->advance.y);
 
             if (fRec.fFlags & kDevKernText_Flag) {
                 glyph->fRsbDelta = SkToS8(fFace->glyph->rsb_delta);
                 glyph->fLsbDelta = SkToS8(fFace->glyph->lsb_delta);
             }
         }
     }
 
-    if (fFace->glyph->format == FT_GLYPH_FORMAT_BITMAP && fScaleY && fFace->size->metrics.y_ppem) {
+    // Do not try to scale embedded bitmaps; only scale bitmaps in bitmap only fonts.
+    if (fFace->glyph->format == FT_GLYPH_FORMAT_BITMAP && !FT_IS_SCALABLE(fFace) &&
+        fScaleY && fFace->size->metrics.y_ppem)

[mtklein, 2014/09/22 18:50:42]

First check is now obsolete?

[bungeman-skia, 2014/09/22 19:02:52]

Indeed it is. It makes more sense to say !FT_IS_SCALABLE(fFace) instead of
fFace->glyph->format == FT_GLYPH_FORMAT_BITMAP here in any event. Updated and
changed comment to reflect rationale.

+    {
         // NOTE: both dimensions are scaled by y_ppem. this is WAI.
         scaleGlyphMetrics(*glyph, SkScalarDiv(SkFixedToScalar(fScaleY),
                                               SkIntToScalar(fFace->size->metrics.y_ppem)));
     }
 
 #ifdef ENABLE_GLYPH_SPEW
     SkDEBUGF(("FT_Set_Char_Size(this:%p sx:%x sy:%x ", this, fScaleX, fScaleY));
     SkDEBUGF(("Metrics(glyph:%d flags:0x%x) w:%d\n", glyph->getGlyphID(), fLoadGlyphFlags, glyph->fWidth));
 #endif
 }
@@ skipping 402 matching lines @@
         *style = (SkTypeface::Style) tempStyle;
     }
     if (isFixedPitch) {
         *isFixedPitch = FT_IS_FIXED_WIDTH(face);
     }
 
     FT_Done_Face(face);
     FT_Done_FreeType(library);
     return true;
 }