Change type of SkScalerContext_FreeType::fScaleX/Y. All uses want FT_F26Dot6.

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"
 #include "SkCanvas.h"
@@ skipping 182 matching lines @@
     void generateMetrics(SkGlyph* glyph) override;
     void generateImage(const SkGlyph& glyph) override;
     void generatePath(const SkGlyph& glyph, SkPath* path) override;
     void generateFontMetrics(SkPaint::FontMetrics*) override;
     SkUnichar generateGlyphToChar(uint16_t glyph) override;
 
 private:
     FT_Face     fFace;              // reference to shared face in gFaceRecHead
     FT_Size     fFTSize;            // our own copy
     FT_Int      fStrikeIndex;
-    SkFixed     fScaleX, fScaleY;
+    FT_F26Dot6  fScaleX, fScaleY;
     FT_Matrix   fMatrix22;
     uint32_t    fLoadGlyphFlags;
     bool        fDoLinearMetrics;
     bool        fLCDIsVert;
 
     // Need scalar versions for generateFontMetrics
     SkVector    fScale;
     SkMatrix    fMatrix22Scalar;
 
     FT_Error setupSize();
@@ skipping 519 matching lines @@
         FT_Error err = FT_Get_Kerning(face, glyphs[i], glyphs[i+1],
                                       FT_KERNING_UNSCALED, &delta);
         if (err) {
             return false;
         }
         adjustments[i] = delta.x;
     }
     return true;
 }
 
-static FT_Int chooseBitmapStrike(FT_Face face, SkFixed scaleY) {
+static FT_Int chooseBitmapStrike(FT_Face face, FT_F26Dot6 scaleY) {
     // early out if face is bad
     if (face == nullptr) {
         SkDEBUGF(("chooseBitmapStrike aborted due to nullptr face\n"));
         return -1;
     }
     // determine target ppem
-    FT_Pos targetPPEM = SkFixedToFDot6(scaleY);
+    FT_Pos targetPPEM = scaleY;
     // find a bitmap strike equal to or just larger than the requested size
     FT_Int chosenStrikeIndex = -1;
     FT_Pos chosenPPEM = 0;
     for (FT_Int strikeIndex = 0; strikeIndex < face->num_fixed_sizes; ++strikeIndex) {
         FT_Pos thisPPEM = face->available_sizes[strikeIndex].y_ppem;
         if (thisPPEM == targetPPEM) {
             // exact match - our search stops here
             chosenPPEM = thisPPEM;
             chosenStrikeIndex = strikeIndex;
             break;
@@ skipping 37 matching lines @@
     fFTSize = nullptr;
     fFace = ref_ft_face(typeface);
     if (nullptr == fFace) {
         return;
     }
 
     fRec.computeMatrices(SkScalerContextRec::kFull_PreMatrixScale, &fScale, &fMatrix22Scalar);
     fMatrix22Scalar.setSkewX(-fMatrix22Scalar.getSkewX());
     fMatrix22Scalar.setSkewY(-fMatrix22Scalar.getSkewY());
 
-    fScaleX = SkScalarToFixed(fScale.fX);
-    fScaleY = SkScalarToFixed(fScale.fY);
+    fScaleX = SkScalarToFDot6(fScale.fX);
+    fScaleY = SkScalarToFDot6(fScale.fY);
     fMatrix22.xx = SkScalarToFixed(fMatrix22Scalar.getScaleX());
     fMatrix22.xy = SkScalarToFixed(fMatrix22Scalar.getSkewX());
     fMatrix22.yx = SkScalarToFixed(fMatrix22Scalar.getSkewY());
     fMatrix22.yy = SkScalarToFixed(fMatrix22Scalar.getScaleY());
 
     fLCDIsVert = SkToBool(fRec.fFlags & SkScalerContext::kLCD_Vertical_Flag);
 
     // compute the flags we send to Load_Glyph
     bool linearMetrics = SkToBool(fRec.fFlags & SkScalerContext::kSubpixelPositioning_Flag);
     {
@@ skipping 71 matching lines @@
     }
     err = FT_Activate_Size(fFTSize);
     if (err != 0) {
         SkDEBUGF(("FT_Activate_Size(%08x, 0x%x, 0x%x) returned 0x%x\n", fFace, fScaleX, fScaleY,
                   err));
         fFTSize = nullptr;
         return;
     }
 
     if (FT_IS_SCALABLE(fFace)) {
-        err = FT_Set_Char_Size(fFace, SkFixedToFDot6(fScaleX), SkFixedToFDot6(fScaleY), 72, 72);
+        err = FT_Set_Char_Size(fFace, fScaleX, fScaleY, 72, 72);
         if (err != 0) {
             SkDEBUGF(("FT_Set_CharSize(%08x, 0x%x, 0x%x) returned 0x%x\n",
                                     fFace, fScaleX, fScaleY,      err));
             fFace = nullptr;
             return;
         }
         FT_Set_Transform(fFace, &fMatrix22, nullptr);
     } else if (FT_HAS_FIXED_SIZES(fFace)) {
         fStrikeIndex = chooseBitmapStrike(fFace, fScaleY);
         if (fStrikeIndex == -1) {
             SkDEBUGF(("no glyphs for font \"%s\" size %f?\n",
-                            fFace->family_name,       SkFixedToScalar(fScaleY)));
+                            fFace->family_name, SkFDot6ToScalar(fScaleY)));

[bungeman-skia, 2016/02/19 20:28:10]

The odd spacing is to line up the variables under the associated substitution.

[dogben, 2016/02/19 22:52:20]

Fixed.

         } else {
             // FreeType does no provide linear metrics for bitmap fonts.
             linearMetrics = false;
 
             // FreeType documentation says:
             // FT_LOAD_NO_BITMAP -- Ignore bitmap strikes when loading.
             // Bitmap-only fonts ignore this flag.
             //
             // However, in FreeType 2.5.1 color bitmap only fonts do not ignore this flag.
             // Force this flag off for bitmap only fonts.
             fLoadGlyphFlags &= ~FT_LOAD_NO_BITMAP;
         }
     } else {
         SkDEBUGF(("unknown kind of font \"%s\" size %f?\n",
-                            fFace->family_name,       SkFixedToScalar(fScaleY)));
+                            fFace->family_name, SkFDot6ToScalar(fScaleY)));
     }
 
     fDoLinearMetrics = linearMetrics;
 }
 
 SkScalerContext_FreeType::~SkScalerContext_FreeType() {
     SkAutoMutexAcquire  ac(gFTMutex);
 
     if (fFTSize != nullptr) {
         FT_Done_Size(fFTSize);
@@ skipping 243 matching lines @@
                 glyph->fRsbDelta = SkToS8(fFace->glyph->rsb_delta);
                 glyph->fLsbDelta = SkToS8(fFace->glyph->lsb_delta);
             }
         }
     }
 
     // If the font isn't scalable, scale the metrics from the non-scalable strike.
     // This means do not try to scale embedded bitmaps; only scale bitmaps in bitmap only fonts.
     if (!FT_IS_SCALABLE(fFace) && fScaleY && fFace->size->metrics.y_ppem) {
         // NOTE: both dimensions are scaled by y_ppem. this is WAI.
-        scaleGlyphMetrics(*glyph, SkFixedToScalar(fScaleY) / fFace->size->metrics.y_ppem);
+        scaleGlyphMetrics(*glyph, SkFDot6ToScalar(fScaleY) / fFace->size->metrics.y_ppem);

[bungeman-skia, 2016/02/19 20:28:09]

I'm pretty sure the gm change is due to this now having less precision.

[dogben, 2016/02/19 22:52:20]

Fixed.

     }
 
 #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
 }
 
 static void clear_glyph_image(const SkGlyph& glyph) {
     sk_bzero(glyph.fImage, glyph.rowBytes() * glyph.fHeight);
@@ skipping 585 matching lines @@
                 SkDEBUGF(("Requested font axis not found: %s '%c%c%c%c'\n",
                           name.c_str(),
                           (skTag >> 24) & 0xFF,
                           (skTag >> 16) & 0xFF,
                           (skTag >>  8) & 0xFF,
                           (skTag)       & 0xFF));
             }
         }
     )
 }