Adding debug SkScalerContext which returns random mask formats

src/fonts/SkRandomScalerContext.cpp

 /*
- * Copyright 2013 Google Inc.
+ * Copyright 2015 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
-#include "SkGScalerContext.h"
+#include "SkRandomScalerContext.h"
 #include "SkGlyph.h"
 #include "SkPath.h"
 #include "SkCanvas.h"
 
-class SkGScalerContext : public SkScalerContext {
+class SkRandomScalerContext : public SkScalerContext {
 public:
-    SkGScalerContext(SkGTypeface*, const SkDescriptor*);
-    virtual ~SkGScalerContext();
+    SkRandomScalerContext(SkRandomTypeface*, const SkDescriptor*);
+    virtual ~SkRandomScalerContext();
 
 protected:
     unsigned generateGlyphCount() override;
     uint16_t generateCharToGlyph(SkUnichar) override;
     void generateAdvance(SkGlyph*) override;
     void generateMetrics(SkGlyph*) override;
     void generateImage(const SkGlyph&) override;
     void generatePath(const SkGlyph&, SkPath*) override;
     void generateFontMetrics(SkPaint::FontMetrics*) override;
 
 private:
-    SkGTypeface*     fFace;
+    SkRandomTypeface*     fFace;
     SkScalerContext* fProxy;
     SkMatrix         fMatrix;
 };
 
 #define STD_SIZE    1
 
 #include "SkDescriptor.h"
 
-SkGScalerContext::SkGScalerContext(SkGTypeface* face, const SkDescriptor* desc)
+SkRandomScalerContext::SkRandomScalerContext(SkRandomTypeface* face, const SkDescriptor* desc)
         : SkScalerContext(face, desc)
-        , fFace(face)
-{
-
+        , fFace(face) {
     size_t  descSize = SkDescriptor::ComputeOverhead(1) + sizeof(SkScalerContext::Rec);
     SkAutoDescriptor ad(descSize);
     SkDescriptor*    newDesc = ad.getDesc();
 
     newDesc->init();
     void* entry = newDesc->addEntry(kRec_SkDescriptorTag,
                                     sizeof(SkScalerContext::Rec), &fRec);
     {
         SkScalerContext::Rec* rec = (SkScalerContext::Rec*)entry;
         rec->fTextSize = STD_SIZE;
         rec->fPreScaleX = SK_Scalar1;
         rec->fPreSkewX = 0;
         rec->fPost2x2[0][0] = rec->fPost2x2[1][1] = SK_Scalar1;
         rec->fPost2x2[1][0] = rec->fPost2x2[0][1] = 0;
     }
     SkASSERT(descSize == newDesc->getLength());
     newDesc->computeChecksum();
 
     fProxy = face->proxy()->createScalerContext(newDesc);
 
     fRec.getSingleMatrix(&fMatrix);
     fMatrix.preScale(SK_Scalar1 / STD_SIZE, SK_Scalar1 / STD_SIZE);
 }
 
-SkGScalerContext::~SkGScalerContext() {
+SkRandomScalerContext::~SkRandomScalerContext() {
     SkDELETE(fProxy);
 }
 
-unsigned SkGScalerContext::generateGlyphCount() {
+unsigned SkRandomScalerContext::generateGlyphCount() {
     return fProxy->getGlyphCount();
 }
 
-uint16_t SkGScalerContext::generateCharToGlyph(SkUnichar uni) {
+uint16_t SkRandomScalerContext::generateCharToGlyph(SkUnichar uni) {
     return fProxy->charToGlyphID(uni);
 }
 
-void SkGScalerContext::generateAdvance(SkGlyph* glyph) {
+void SkRandomScalerContext::generateAdvance(SkGlyph* glyph) {
     fProxy->getAdvance(glyph);
 
     SkVector advance;
     fMatrix.mapXY(SkFixedToScalar(glyph->fAdvanceX),
                   SkFixedToScalar(glyph->fAdvanceY), &advance);
     glyph->fAdvanceX = SkScalarToFixed(advance.fX);
     glyph->fAdvanceY = SkScalarToFixed(advance.fY);
 }
 
-void SkGScalerContext::generateMetrics(SkGlyph* glyph) {
+void SkRandomScalerContext::generateMetrics(SkGlyph* glyph) {
     fProxy->getMetrics(glyph);
 
     SkVector advance;
     fMatrix.mapXY(SkFixedToScalar(glyph->fAdvanceX),
                   SkFixedToScalar(glyph->fAdvanceY), &advance);
     glyph->fAdvanceX = SkScalarToFixed(advance.fX);
     glyph->fAdvanceY = SkScalarToFixed(advance.fY);
 
     SkPath path;
     fProxy->getPath(*glyph, &path);
     path.transform(fMatrix);
 
     SkRect storage;
     const SkPaint& paint = fFace->paint();
     const SkRect& newBounds = paint.doComputeFastBounds(path.getBounds(),
                                                         &storage,
                                                         SkPaint::kFill_Style);
     SkIRect ibounds;
     newBounds.roundOut(&ibounds);
     glyph->fLeft = ibounds.fLeft;
     glyph->fTop = ibounds.fTop;
     glyph->fWidth = ibounds.width();
     glyph->fHeight = ibounds.height();
-    glyph->fMaskFormat = SkMask::kARGB32_Format;
+
+    // Here we will change the mask format of the glyph
+    // NOTE this is being overridden by the base class
+    SkMask::Format format;
+    switch (glyph->getGlyphID() % 3) {
+        case 0:
+            format = SkMask::kLCD16_Format;
+            break;
+        case 1:
+            format = SkMask::kA8_Format;
+            break;
+        default:
+            format = SkMask::kARGB32_Format;
+    }
+
+    glyph->fMaskFormat = format;
 }
 
-void SkGScalerContext::generateImage(const SkGlyph& glyph) {
+void SkRandomScalerContext::generateImage(const SkGlyph& glyph) {
+    SkMask::Format format = static_cast<SkMask::Format>(glyph.fMaskFormat);
     if (SkMask::kARGB32_Format == glyph.fMaskFormat) {
         SkPath path;
         fProxy->getPath(glyph, &path);
 
         SkBitmap bm;
         bm.installPixels(SkImageInfo::MakeN32Premul(glyph.fWidth, glyph.fHeight),
                          glyph.fImage, glyph.rowBytes());
         bm.eraseColor(0);
 
         SkCanvas canvas(bm);
         canvas.translate(-SkIntToScalar(glyph.fLeft),
                          -SkIntToScalar(glyph.fTop));
         canvas.concat(fMatrix);
         canvas.drawPath(path, fFace->paint());
     } else {
         fProxy->getImage(glyph);
     }
+
+    SkASSERT(glyph.fMaskFormat == format);

[bungeman-skia, 2015/07/24 18:43:53]

Even with SkScalerContext not overriding things, this is currently false on GDI.
DW knows ahead of time if it's going to get BW, but GDI doesn't.

 }
 
-void SkGScalerContext::generatePath(const SkGlyph& glyph, SkPath* path) {
+void SkRandomScalerContext::generatePath(const SkGlyph& glyph, SkPath* path) {
     fProxy->getPath(glyph, path);
     path->transform(fMatrix);
 }
 
-void SkGScalerContext::generateFontMetrics(SkPaint::FontMetrics* metrics) {
+void SkRandomScalerContext::generateFontMetrics(SkPaint::FontMetrics* metrics) {
     fProxy->getFontMetrics(metrics);
     if (metrics) {
         SkScalar scale = fMatrix.getScaleY();
         metrics->fTop = SkScalarMul(metrics->fTop, scale);
         metrics->fAscent = SkScalarMul(metrics->fAscent, scale);
         metrics->fDescent = SkScalarMul(metrics->fDescent, scale);
         metrics->fBottom = SkScalarMul(metrics->fBottom, scale);
         metrics->fLeading = SkScalarMul(metrics->fLeading, scale);
         metrics->fAvgCharWidth = SkScalarMul(metrics->fAvgCharWidth, scale);
         metrics->fXMin = SkScalarMul(metrics->fXMin, scale);
         metrics->fXMax = SkScalarMul(metrics->fXMax, scale);
         metrics->fXHeight = SkScalarMul(metrics->fXHeight, scale);
     }
 }
 
 ///////////////////////////////////////////////////////////////////////////////
 
 #include "SkTypefaceCache.h"
 
-SkGTypeface::SkGTypeface(SkTypeface* proxy, const SkPaint& paint)
+SkRandomTypeface::SkRandomTypeface(SkTypeface* proxy, const SkPaint& paint)
     : SkTypeface(proxy->fontStyle(), SkTypefaceCache::NewFontID(), false)
     , fProxy(SkRef(proxy))
     , fPaint(paint) {}
 
-SkGTypeface::~SkGTypeface() {
+SkRandomTypeface::~SkRandomTypeface() {
     fProxy->unref();
 }
 
-SkScalerContext* SkGTypeface::onCreateScalerContext(
+SkScalerContext* SkRandomTypeface::onCreateScalerContext(
                                             const SkDescriptor* desc) const {
-    return SkNEW_ARGS(SkGScalerContext, (const_cast<SkGTypeface*>(this), desc));
+    return SkNEW_ARGS(SkRandomScalerContext, (const_cast<SkRandomTypeface*>(this), desc));
 }
 
-void SkGTypeface::onFilterRec(SkScalerContextRec* rec) const {
+void SkRandomTypeface::onFilterRec(SkScalerContextRec* rec) const {
     fProxy->filterRec(rec);
     rec->setHinting(SkPaint::kNo_Hinting);
     rec->fMaskFormat = SkMask::kARGB32_Format;
 }
 
-SkAdvancedTypefaceMetrics* SkGTypeface::onGetAdvancedTypefaceMetrics(
+SkAdvancedTypefaceMetrics* SkRandomTypeface::onGetAdvancedTypefaceMetrics(
                                 PerGlyphInfo info,
                                 const uint32_t* glyphIDs,
                                 uint32_t glyphIDsCount) const {
     return fProxy->getAdvancedTypefaceMetrics(info, glyphIDs, glyphIDsCount);
 }
 
-SkStreamAsset* SkGTypeface::onOpenStream(int* ttcIndex) const {
+SkStreamAsset* SkRandomTypeface::onOpenStream(int* ttcIndex) const {
     return fProxy->openStream(ttcIndex);
 }
 
-void SkGTypeface::onGetFontDescriptor(SkFontDescriptor* desc,
+void SkRandomTypeface::onGetFontDescriptor(SkFontDescriptor* desc,
                                       bool* isLocal) const {
     fProxy->getFontDescriptor(desc, isLocal);
 }
 
-int SkGTypeface::onCharsToGlyphs(const void* chars, Encoding encoding,
+int SkRandomTypeface::onCharsToGlyphs(const void* chars, Encoding encoding,
                                  uint16_t glyphs[], int glyphCount) const {
     return fProxy->charsToGlyphs(chars, encoding, glyphs, glyphCount);
 }
 
-int SkGTypeface::onCountGlyphs() const {
+int SkRandomTypeface::onCountGlyphs() const {
     return fProxy->countGlyphs();
 }
 
-int SkGTypeface::onGetUPEM() const {
+int SkRandomTypeface::onGetUPEM() const {
     return fProxy->getUnitsPerEm();
 }
 
-void SkGTypeface::onGetFamilyName(SkString* familyName) const {
+void SkRandomTypeface::onGetFamilyName(SkString* familyName) const {
     fProxy->getFamilyName(familyName);
 }
 
-SkTypeface::LocalizedStrings* SkGTypeface::onCreateFamilyNameIterator() const {
+SkTypeface::LocalizedStrings* SkRandomTypeface::onCreateFamilyNameIterator() const {
     return fProxy->createFamilyNameIterator();
 }
 
-int SkGTypeface::onGetTableTags(SkFontTableTag tags[]) const {
+int SkRandomTypeface::onGetTableTags(SkFontTableTag tags[]) const {
     return fProxy->getTableTags(tags);
 }
 
-size_t SkGTypeface::onGetTableData(SkFontTableTag tag, size_t offset,
+size_t SkRandomTypeface::onGetTableData(SkFontTableTag tag, size_t offset,
                                     size_t length, void* data) const {
     return fProxy->getTableData(tag, offset, length, data);
 }
 
-///////////////////////////////////////////////////////////////////////////////
-
-#if 0
-// under construction -- defining a font purely in terms of skia primitives
-// ala an SVG-font.
-class SkGFont : public SkRefCnt {
-public:
-    virtual ~SkGFont();
-
-    int unicharToGlyph(SkUnichar) const;
-
-    int countGlyphs() const { return fCount; }
-
-    float getAdvance(int index) const {
-        SkASSERT((unsigned)index < (unsigned)fCount);
-        return fGlyphs[index].fAdvance;
-    }
-
-    const SkPath& getPath(int index) const {
-        SkASSERT((unsigned)index < (unsigned)fCount);
-        return fGlyphs[index].fPath;
-    }
-
-private:
-    struct Glyph {
-        SkUnichar   fUni;
-        float       fAdvance;
-        SkPath      fPath;
-    };
-    int fCount;
-    Glyph* fGlyphs;
-
-    friend class SkGFontBuilder;
-    SkGFont(int count, Glyph* array);
-};
-
-class SkGFontBuilder {
-public:
-
-};
-#endif