michael@0: /*
michael@0:  * Copyright 2010 Google Inc.
michael@0:  *
michael@0:  * Use of this source code is governed by a BSD-style license that can be
michael@0:  * found in the LICENSE file.
michael@0:  */
michael@0: 
michael@0: #include "GrAtlas.h"
michael@0: #include "GrGpu.h"
michael@0: #include "GrRectanizer.h"
michael@0: #include "GrTextStrike.h"
michael@0: #include "GrTextStrike_impl.h"
michael@0: #include "SkString.h"
michael@0: 
michael@0: #include "SkDistanceFieldGen.h"
michael@0: 
michael@0: ///////////////////////////////////////////////////////////////////////////////
michael@0: 
michael@0: #define FONT_CACHE_STATS 0
michael@0: #if FONT_CACHE_STATS
michael@0: static int g_PurgeCount = 0;
michael@0: #endif
michael@0: 
michael@0: GrFontCache::GrFontCache(GrGpu* gpu) : fGpu(gpu) {
michael@0:     gpu->ref();
michael@0:     for (int i = 0; i < kAtlasCount; ++i) {
michael@0:         fAtlasMgr[i] = NULL;
michael@0:     }
michael@0: 
michael@0:     fHead = fTail = NULL;
michael@0: }
michael@0: 
michael@0: GrFontCache::~GrFontCache() {
michael@0:     fCache.deleteAll();
michael@0:     for (int i = 0; i < kAtlasCount; ++i) {
michael@0:         delete fAtlasMgr[i];
michael@0:     }
michael@0:     fGpu->unref();
michael@0: #if FONT_CACHE_STATS
michael@0:       GrPrintf("Num purges: %d\n", g_PurgeCount);
michael@0: #endif
michael@0: }
michael@0: 
michael@0: static GrPixelConfig mask_format_to_pixel_config(GrMaskFormat format) {
michael@0:     static const GrPixelConfig sPixelConfigs[] = {
michael@0:         kAlpha_8_GrPixelConfig,
michael@0:         kRGB_565_GrPixelConfig,
michael@0:         kSkia8888_GrPixelConfig,
michael@0:         kSkia8888_GrPixelConfig
michael@0:     };
michael@0:     SK_COMPILE_ASSERT(SK_ARRAY_COUNT(sPixelConfigs) == kMaskFormatCount, array_size_mismatch);
michael@0: 
michael@0:     return sPixelConfigs[format];
michael@0: }
michael@0: 
michael@0: static int mask_format_to_atlas_index(GrMaskFormat format) {
michael@0:     static const int sAtlasIndices[] = {
michael@0:         GrFontCache::kA8_AtlasType,
michael@0:         GrFontCache::k565_AtlasType,
michael@0:         GrFontCache::k8888_AtlasType,
michael@0:         GrFontCache::k8888_AtlasType
michael@0:     };
michael@0:     SK_COMPILE_ASSERT(SK_ARRAY_COUNT(sAtlasIndices) == kMaskFormatCount, array_size_mismatch);
michael@0: 
michael@0:     SkASSERT(sAtlasIndices[format] < GrFontCache::kAtlasCount);
michael@0:     return sAtlasIndices[format];
michael@0: }
michael@0: 
michael@0: GrTextStrike* GrFontCache::generateStrike(GrFontScaler* scaler,
michael@0:                                           const Key& key) {
michael@0:     GrMaskFormat format = scaler->getMaskFormat();
michael@0:     GrPixelConfig config = mask_format_to_pixel_config(format);
michael@0:     int atlasIndex = mask_format_to_atlas_index(format);
michael@0:     if (NULL == fAtlasMgr[atlasIndex]) {
michael@0:         fAtlasMgr[atlasIndex] = SkNEW_ARGS(GrAtlasMgr, (fGpu, config));
michael@0:     }
michael@0:     GrTextStrike* strike = SkNEW_ARGS(GrTextStrike,
michael@0:                                       (this, scaler->getKey(), format, fAtlasMgr[atlasIndex]));
michael@0:     fCache.insert(key, strike);
michael@0: 
michael@0:     if (fHead) {
michael@0:         fHead->fPrev = strike;
michael@0:     } else {
michael@0:         SkASSERT(NULL == fTail);
michael@0:         fTail = strike;
michael@0:     }
michael@0:     strike->fPrev = NULL;
michael@0:     strike->fNext = fHead;
michael@0:     fHead = strike;
michael@0: 
michael@0:     return strike;
michael@0: }
michael@0: 
michael@0: void GrFontCache::freeAll() {
michael@0:     fCache.deleteAll();
michael@0:     for (int i = 0; i < kAtlasCount; ++i) {
michael@0:         delete fAtlasMgr[i];
michael@0:         fAtlasMgr[i] = NULL;
michael@0:     }
michael@0:     fHead = NULL;
michael@0:     fTail = NULL;
michael@0: }
michael@0: 
michael@0: void GrFontCache::purgeStrike(GrTextStrike* strike) {
michael@0:     const GrFontCache::Key key(strike->fFontScalerKey);
michael@0:     fCache.remove(key, strike);
michael@0:     this->detachStrikeFromList(strike);
michael@0:     delete strike;
michael@0: }
michael@0: 
michael@0: bool GrFontCache::freeUnusedPlot(GrTextStrike* preserveStrike) {
michael@0:     SkASSERT(NULL != preserveStrike);
michael@0: 
michael@0:     GrAtlasMgr* atlasMgr = preserveStrike->fAtlasMgr;
michael@0:     GrPlot* plot = atlasMgr->getUnusedPlot();
michael@0:     if (NULL == plot) {
michael@0:         return false;
michael@0:     }
michael@0:     plot->resetRects();
michael@0: 
michael@0:     GrTextStrike* strike = fHead;
michael@0:     GrMaskFormat maskFormat = preserveStrike->fMaskFormat;
michael@0:     while (strike) {
michael@0:         if (maskFormat != strike->fMaskFormat) {
michael@0:             strike = strike->fNext;
michael@0:             continue;
michael@0:         }
michael@0: 
michael@0:         GrTextStrike* strikeToPurge = strike;
michael@0:         strike = strikeToPurge->fNext;
michael@0:         strikeToPurge->removePlot(plot);
michael@0: 
michael@0:         // clear out any empty strikes (except this one)
michael@0:         if (strikeToPurge != preserveStrike && strikeToPurge->fAtlas.isEmpty()) {
michael@0:             this->purgeStrike(strikeToPurge);
michael@0:         }
michael@0:     }
michael@0: 
michael@0: #if FONT_CACHE_STATS
michael@0:     ++g_PurgeCount;
michael@0: #endif
michael@0: 
michael@0:     return true;
michael@0: }
michael@0: 
michael@0: #ifdef SK_DEBUG
michael@0: void GrFontCache::validate() const {
michael@0:     int count = fCache.count();
michael@0:     if (0 == count) {
michael@0:         SkASSERT(!fHead);
michael@0:         SkASSERT(!fTail);
michael@0:     } else if (1 == count) {
michael@0:         SkASSERT(fHead == fTail);
michael@0:     } else {
michael@0:         SkASSERT(fHead != fTail);
michael@0:     }
michael@0: 
michael@0:     int count2 = 0;
michael@0:     const GrTextStrike* strike = fHead;
michael@0:     while (strike) {
michael@0:         count2 += 1;
michael@0:         strike = strike->fNext;
michael@0:     }
michael@0:     SkASSERT(count == count2);
michael@0: 
michael@0:     count2 = 0;
michael@0:     strike = fTail;
michael@0:     while (strike) {
michael@0:         count2 += 1;
michael@0:         strike = strike->fPrev;
michael@0:     }
michael@0:     SkASSERT(count == count2);
michael@0: }
michael@0: #endif
michael@0: 
michael@0: #ifdef SK_DEVELOPER
michael@0: void GrFontCache::dump() const {
michael@0:     static int gDumpCount = 0;
michael@0:     for (int i = 0; i < kAtlasCount; ++i) {
michael@0:         if (NULL != fAtlasMgr[i]) {
michael@0:             GrTexture* texture = fAtlasMgr[i]->getTexture();
michael@0:             if (NULL != texture) {
michael@0:                 SkString filename;
michael@0:                 filename.printf("fontcache_%d%d.png", gDumpCount, i);
michael@0:                 texture->savePixels(filename.c_str());
michael@0:             }
michael@0:         }
michael@0:     }
michael@0:     ++gDumpCount;
michael@0: }
michael@0: #endif
michael@0: 
michael@0: ///////////////////////////////////////////////////////////////////////////////
michael@0: 
michael@0: #ifdef SK_DEBUG
michael@0:     static int gCounter;
michael@0: #endif
michael@0: 
michael@0: // this acts as the max magnitude for the distance field,
michael@0: // as well as the pad we need around the glyph
michael@0: #define DISTANCE_FIELD_RANGE   4
michael@0: 
michael@0: /*
michael@0:     The text strike is specific to a given font/style/matrix setup, which is
michael@0:     represented by the GrHostFontScaler object we are given in getGlyph().
michael@0: 
michael@0:     We map a 32bit glyphID to a GrGlyph record, which in turn points to a
michael@0:     atlas and a position within that texture.
michael@0:  */
michael@0: 
michael@0: GrTextStrike::GrTextStrike(GrFontCache* cache, const GrKey* key,
michael@0:                            GrMaskFormat format,
michael@0:                            GrAtlasMgr* atlasMgr) : fPool(64) {
michael@0:     fFontScalerKey = key;
michael@0:     fFontScalerKey->ref();
michael@0: 
michael@0:     fFontCache = cache;     // no need to ref, it won't go away before we do
michael@0:     fAtlasMgr = atlasMgr;   // no need to ref, it won't go away before we do
michael@0: 
michael@0:     fMaskFormat = format;
michael@0: 
michael@0: #ifdef SK_DEBUG
michael@0: //    GrPrintf(" GrTextStrike %p %d\n", this, gCounter);
michael@0:     gCounter += 1;
michael@0: #endif
michael@0: }
michael@0: 
michael@0: // this signature is needed because it's used with
michael@0: // SkTDArray::visitAll() (see destructor)
michael@0: static void free_glyph(GrGlyph*& glyph) { glyph->free(); }
michael@0: 
michael@0: GrTextStrike::~GrTextStrike() {
michael@0:     fFontScalerKey->unref();
michael@0:     fCache.getArray().visitAll(free_glyph);
michael@0: 
michael@0: #ifdef SK_DEBUG
michael@0:     gCounter -= 1;
michael@0: //    GrPrintf("~GrTextStrike %p %d\n", this, gCounter);
michael@0: #endif
michael@0: }
michael@0: 
michael@0: GrGlyph* GrTextStrike::generateGlyph(GrGlyph::PackedID packed,
michael@0:                                      GrFontScaler* scaler) {
michael@0:     SkIRect bounds;
michael@0:     if (!scaler->getPackedGlyphBounds(packed, &bounds)) {
michael@0:         return NULL;
michael@0:     }
michael@0: 
michael@0:     GrGlyph* glyph = fPool.alloc();
michael@0:     // expand bounds to hold full distance field data
michael@0:     if (fUseDistanceField) {
michael@0:         bounds.fLeft   -= DISTANCE_FIELD_RANGE;
michael@0:         bounds.fRight  += DISTANCE_FIELD_RANGE;
michael@0:         bounds.fTop    -= DISTANCE_FIELD_RANGE;
michael@0:         bounds.fBottom += DISTANCE_FIELD_RANGE;
michael@0:     }
michael@0:     glyph->init(packed, bounds);
michael@0:     fCache.insert(packed, glyph);
michael@0:     return glyph;
michael@0: }
michael@0: 
michael@0: void GrTextStrike::removePlot(const GrPlot* plot) {
michael@0:     SkTDArray<GrGlyph*>& glyphArray = fCache.getArray();
michael@0:     for (int i = 0; i < glyphArray.count(); ++i) {
michael@0:         if (plot == glyphArray[i]->fPlot) {
michael@0:             glyphArray[i]->fPlot = NULL;
michael@0:         }
michael@0:     }
michael@0: 
michael@0:     fAtlasMgr->removePlot(&fAtlas, plot);
michael@0: }
michael@0: 
michael@0: 
michael@0: bool GrTextStrike::addGlyphToAtlas(GrGlyph* glyph, GrFontScaler* scaler) {
michael@0: #if 0   // testing hack to force us to flush our cache often
michael@0:     static int gCounter;
michael@0:     if ((++gCounter % 10) == 0) return false;
michael@0: #endif
michael@0: 
michael@0:     SkASSERT(glyph);
michael@0:     SkASSERT(scaler);
michael@0:     SkASSERT(fCache.contains(glyph));
michael@0:     SkASSERT(NULL == glyph->fPlot);
michael@0: 
michael@0:     SkAutoRef ar(scaler);
michael@0: 
michael@0:     int bytesPerPixel = GrMaskFormatBytesPerPixel(fMaskFormat);
michael@0: 
michael@0:     GrPlot* plot;
michael@0:     if (fUseDistanceField) {
michael@0:         // we've already expanded the glyph dimensions to match the final size
michael@0:         // but must shrink back down to get the packed glyph data
michael@0:         int dfWidth = glyph->width();
michael@0:         int dfHeight = glyph->height();
michael@0:         int width = dfWidth - 2*DISTANCE_FIELD_RANGE;
michael@0:         int height = dfHeight - 2*DISTANCE_FIELD_RANGE;
michael@0:         int stride = width*bytesPerPixel;
michael@0: 
michael@0:         size_t size = width * height * bytesPerPixel;
michael@0:         SkAutoSMalloc<1024> storage(size);
michael@0:         if (!scaler->getPackedGlyphImage(glyph->fPackedID, width, height, stride, storage.get())) {
michael@0:             return false;
michael@0:         }
michael@0: 
michael@0:         // alloc storage for distance field glyph
michael@0:         size_t dfSize = dfWidth * dfHeight * bytesPerPixel;
michael@0:         SkAutoSMalloc<1024> dfStorage(dfSize);
michael@0: 
michael@0:         if (1 == bytesPerPixel) {
michael@0:             (void) SkGenerateDistanceFieldFromImage((unsigned char*)dfStorage.get(),
michael@0:                                                     (unsigned char*)storage.get(),
michael@0:                                                     width, height, DISTANCE_FIELD_RANGE);
michael@0:         } else {
michael@0:             // TODO: Fix color emoji
michael@0:             // for now, copy glyph into distance field storage
michael@0:             // this is not correct, but it won't crash
michael@0:             sk_bzero(dfStorage.get(), dfSize);
michael@0:             unsigned char* ptr = (unsigned char*) storage.get();
michael@0:             unsigned char* dfPtr = (unsigned char*) dfStorage.get();
michael@0:             size_t dfStride = dfWidth*bytesPerPixel;
michael@0:             dfPtr += DISTANCE_FIELD_RANGE*dfStride;
michael@0:             dfPtr += DISTANCE_FIELD_RANGE*bytesPerPixel;
michael@0: 
michael@0:             for (int i = 0; i < height; ++i) {
michael@0:                 memcpy(dfPtr, ptr, stride);
michael@0: 
michael@0:                 dfPtr += dfStride;
michael@0:                 ptr += stride;
michael@0:             }
michael@0:         }
michael@0: 
michael@0:         // copy to atlas
michael@0:         plot = fAtlasMgr->addToAtlas(&fAtlas, dfWidth, dfHeight, dfStorage.get(),
michael@0:                                      &glyph->fAtlasLocation);
michael@0: 
michael@0:     } else {
michael@0:         size_t size = glyph->fBounds.area() * bytesPerPixel;
michael@0:         SkAutoSMalloc<1024> storage(size);
michael@0:         if (!scaler->getPackedGlyphImage(glyph->fPackedID, glyph->width(),
michael@0:                                          glyph->height(),
michael@0:                                          glyph->width() * bytesPerPixel,
michael@0:                                          storage.get())) {
michael@0:             return false;
michael@0:         }
michael@0: 
michael@0:         plot = fAtlasMgr->addToAtlas(&fAtlas, glyph->width(),
michael@0:                                      glyph->height(), storage.get(),
michael@0:                                      &glyph->fAtlasLocation);
michael@0:     }
michael@0: 
michael@0:     if (NULL == plot) {
michael@0:         return false;
michael@0:     }
michael@0: 
michael@0:     glyph->fPlot = plot;
michael@0:     return true;
michael@0: }