Move distance field generation to the glyph cache

src/gpu/SkGrFontScaler.cpp

 
 /*
  * Copyright 2010 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 
 #include "GrTemplates.h"
 #include "SkGr.h"
 #include "SkDescriptor.h"
+#include "SkDistanceFieldGen.h"
 #include "SkGlyphCache.h"
 
 class SkGrDescKey : public GrKey {
 public:
     explicit SkGrDescKey(const SkDescriptor& desc);
     virtual ~SkGrDescKey();
 
 protected:
     // overrides
     virtual bool lt(const GrKey& rh) const;
@@ skipping 78 matching lines @@
     }
     return fKey;
 }
 
 bool SkGrFontScaler::getPackedGlyphBounds(GrGlyph::PackedID packed,
                                           SkIRect* bounds) {
     const SkGlyph& glyph = fStrike->getGlyphIDMetrics(GrGlyph::UnpackID(packed),
                                               GrGlyph::UnpackFixedX(packed),
                                               GrGlyph::UnpackFixedY(packed));
     bounds->setXYWH(glyph.fLeft, glyph.fTop, glyph.fWidth, glyph.fHeight);
+
     return true;
+}
 
+bool SkGrFontScaler::getPackedGlyphDFBounds(GrGlyph::PackedID packed,

[robertphillips, 2014/04/11 14:13:00]

Align or fit on one line?

[jvanverth1, 2014/04/11 17:54:14]

Done.

+                                          SkIRect* bounds) {
+    const SkGlyph& glyph = fStrike->getGlyphIDMetrics(GrGlyph::UnpackID(packed),

[robertphillips, 2014/04/11 14:13:00]

align?

[jvanverth1, 2014/04/11 17:54:14]

Done.

+                                              GrGlyph::UnpackFixedX(packed),
+                                              GrGlyph::UnpackFixedY(packed));
+    bounds->setXYWH(glyph.fLeft, glyph.fTop, glyph.fWidth, glyph.fHeight);
+    bounds->outset(SK_DistanceFieldPad, SK_DistanceFieldPad);
+
+    return true;
 }
 
 namespace {
 // expands each bit in a bitmask to 0 or ~0 of type INT_TYPE. Used to expand a BW glyph mask to
 // A8, RGB565, or RGBA8888.
 template <typename INT_TYPE>
 void expand_bits(INT_TYPE* dst,
                  const uint8_t* src,
                  int width,
                  int height,
@@ skipping 60 matching lines @@
         const int bbp = GrMaskFormatBytesPerPixel(this->getMaskFormat());
         for (int y = 0; y < height; y++) {
             memcpy(dst, src, width * bbp);
             src = (const char*)src + srcRB;
             dst = (char*)dst + dstRB;
         }
     }
     return true;
 }
 
+bool SkGrFontScaler::getPackedGlyphDFImage(GrGlyph::PackedID packed,
+                                           int width, int height,
+                                           int dstRB, void* dst) {
+    const SkGlyph& glyph = fStrike->getGlyphIDMetrics(GrGlyph::UnpackID(packed),

[robertphillips, 2014/04/11 14:13:00]

align?

[jvanverth1, 2014/04/11 17:54:14]

Done.

+                                              GrGlyph::UnpackFixedX(packed),
+                                              GrGlyph::UnpackFixedY(packed));
+    SkASSERT(glyph.fWidth + 2*SK_DistanceFieldPad == width);
+    SkASSERT(glyph.fHeight + 2*SK_DistanceFieldPad == height);
+    const void* src = fStrike->findDistanceField(glyph);
+    if (NULL == src) {
+        return false;
+    }
+

[robertphillips, 2014/04/11 14:13:00]

At a higher-level why are we copying out here?

[jvanverth1, 2014/04/11 17:54:14]

The short answer is: to match getPackedGlyphImage. The long is that I noticed
this as well and the src pointer could be returned directly. The only issue is
that might make the cache less thread-friendly (i.e. what happens if you request
a distance field and another thread deletes it before you copy it to the
driver).

+    memcpy(dst, src, width * height);
+
+    return true;
+}
+
 // we should just return const SkPath* (NULL means false)
 bool SkGrFontScaler::getGlyphPath(uint16_t glyphID, SkPath* path) {
 
     const SkGlyph& glyph = fStrike->getGlyphIDMetrics(glyphID);
     const SkPath* skPath = fStrike->findPath(glyph);
     if (skPath) {
         *path = *skPath;
         return true;
     }
     return false;
 }