Move distance field generation to the glyph cache

src/core/SkGlyphCache.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 "SkGlyphCache.h"
 #include "SkGlyphCache_Globals.h"
+#include "SkDistanceFieldGen.h"
 #include "SkGraphics.h"
 #include "SkPaint.h"
 #include "SkPath.h"
 #include "SkTemplates.h"
 #include "SkTLS.h"
 #include "SkTypeface.h"
 
 //#define SPEW_PURGE_STATUS
 //#define RECORD_HASH_EFFICIENCY
 
@@ skipping 299 matching lines @@
     } else {
         SkASSERT(kFull_MetricsType == mtype);
         fScalerContext->getMetrics(glyph);
     }
 
     return glyph;
 }
 
 const void* SkGlyphCache::findImage(const SkGlyph& glyph) {
     if (glyph.fWidth > 0 && glyph.fWidth < kMaxGlyphWidth) {
-        if (glyph.fImage == NULL) {
+        if (NULL == glyph.fImage) {
             size_t  size = glyph.computeImageSize();
             const_cast<SkGlyph&>(glyph).fImage = fGlyphAlloc.alloc(size,
                                         SkChunkAlloc::kReturnNil_AllocFailType);
             // check that alloc() actually succeeded
-            if (glyph.fImage) {
+            if (NULL != glyph.fImage) {
                 fScalerContext->getImage(glyph);
                 // TODO: the scaler may have changed the maskformat during
                 // getImage (e.g. from AA or LCD to BW) which means we may have
                 // overallocated the buffer. Check if the new computedImageSize
                 // is smaller, and if so, strink the alloc size in fImageAlloc.
                 fMemoryUsed += size;
             }
         }
     }
     return glyph.fImage;
 }
 
 const SkPath* SkGlyphCache::findPath(const SkGlyph& glyph) {
     if (glyph.fWidth) {
         if (glyph.fPath == NULL) {
             const_cast<SkGlyph&>(glyph).fPath = SkNEW(SkPath);
             fScalerContext->getPath(glyph, glyph.fPath);
             fMemoryUsed += sizeof(SkPath) +
                     glyph.fPath->countPoints() * sizeof(SkPoint);
         }
     }
     return glyph.fPath;
 }
 
+const void* SkGlyphCache::findDistanceField(const SkGlyph& glyph) {
+    if (glyph.fWidth > 0 && glyph.fWidth < kMaxGlyphWidth) {
+        if (NULL == glyph.fDistanceField) {
+            size_t  size = SkComputeDistanceFieldSize(glyph.fWidth, glyph.fHeight);
+            if (size == 0) {
+                return NULL;
+            }
+            const void* image = this->findImage(glyph);
+            // now generate the distance field
+            if (NULL != image) {
+                const_cast<SkGlyph&>(glyph).fDistanceField = fGlyphAlloc.alloc(size,
+                                            SkChunkAlloc::kReturnNil_AllocFailType);
+                if (NULL != glyph.fDistanceField) {
+                    SkMask::Format maskFormat = static_cast<SkMask::Format>(glyph.fMaskFormat);
+                    if (SkMask::kA8_Format == maskFormat) {
+                        // make the distance field from the image
+                        SkGenerateDistanceFieldFromA8Image((unsigned char*)glyph.fDistanceField,
+                                                           (unsigned char*)glyph.fImage,
+                                                           glyph.fWidth, glyph.fHeight,
+                                                           glyph.rowBytes());
+                        fMemoryUsed += size;
+                    } else if (SkMask::kBW_Format == maskFormat) {
+                        // make the distance field from the image
+                        SkGenerateDistanceFieldFromBWImage((unsigned char*)glyph.fDistanceField,
+                                                           (unsigned char*)glyph.fImage,
+                                                           glyph.fWidth, glyph.fHeight,
+                                                           glyph.rowBytes());
+                        fMemoryUsed += size;
+                    } else {
+                        fGlyphAlloc.unalloc(glyph.fDistanceField);
+                        const_cast<SkGlyph&>(glyph).fDistanceField = NULL;
+                    }
+                }
+            }
+        }
+    }
+    return glyph.fDistanceField;
+}
+
 ///////////////////////////////////////////////////////////////////////////////
 
 bool SkGlyphCache::getAuxProcData(void (*proc)(void*), void** dataPtr) const {
     const AuxProcRec* rec = fAuxProcList;
     while (rec) {
         if (rec->fProc == proc) {
             if (dataPtr) {
                 *dataPtr = rec->fData;
             }
             return true;
@@ skipping 271 matching lines @@
 void SkGlyphCache::validate() const {
 #ifdef SK_DEBUG_GLYPH_CACHE
     int count = fGlyphArray.count();
     for (int i = 0; i < count; i++) {
         const SkGlyph* glyph = fGlyphArray[i];
         SkASSERT(glyph);
         SkASSERT(fGlyphAlloc.contains(glyph));
         if (glyph->fImage) {
             SkASSERT(fGlyphAlloc.contains(glyph->fImage));
         }
+        if (glyph->fDistanceField) {
+            SkASSERT(fGlyphAlloc.contains(glyph->fDistanceField));
+        }
     }
 #endif
 }
 
 void SkGlyphCache_Globals::validate() const {
     size_t computedBytes = 0;
     int computedCount = 0;
 
     const SkGlyphCache* head = fHead;
     while (head != NULL) {
@@ skipping 47 matching lines @@
     return tls ? tls->getCacheSizeLimit() : 0;
 }
 
 void SkGraphics::SetTLSFontCacheLimit(size_t bytes) {
     if (0 == bytes) {
         SkGlyphCache_Globals::DeleteTLS();
     } else {
         SkGlyphCache_Globals::GetTLS().setCacheSizeLimit(bytes);
     }
 }