/*
* 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 "SkLazyPtr.h"
#include "SkPaint.h"
#include "SkPath.h"
#include "SkTemplates.h"
#include "SkTLS.h"
#include "SkTypeface.h"
//#define SPEW_PURGE_STATUS
//#define RECORD_HASH_EFFICIENCY
namespace {
SkGlyphCache_Globals* create_globals() {
return SkNEW_ARGS(SkGlyphCache_Globals, (SkGlyphCache_Globals::kYes_UseMutex));
}
} // namespace
// Returns the shared globals
static SkGlyphCache_Globals& getSharedGlobals() {
SK_DECLARE_STATIC_LAZY_PTR(SkGlyphCache_Globals, globals, create_globals);
return *globals.get();
}
// Returns the TLS globals (if set), or the shared globals
static SkGlyphCache_Globals& getGlobals() {
SkGlyphCache_Globals* tls = SkGlyphCache_Globals::FindTLS();
return tls ? *tls : getSharedGlobals();
}
///////////////////////////////////////////////////////////////////////////////
#ifdef RECORD_HASH_EFFICIENCY
static uint32_t gHashSuccess;
static uint32_t gHashCollision;
static void RecordHashSuccess() {
gHashSuccess += 1;
}
static void RecordHashCollisionIf(bool pred) {
if (pred) {
gHashCollision += 1;
uint32_t total = gHashSuccess + gHashCollision;
SkDebugf("Font Cache Hash success rate: %d%%\n",
100 * gHashSuccess / total);
}
}
#else
#define RecordHashSuccess() (void)0
#define RecordHashCollisionIf(pred) (void)0
#endif
#define RecordHashCollision() RecordHashCollisionIf(true)
///////////////////////////////////////////////////////////////////////////////
// so we don't grow our arrays a lot
#define kMinGlyphCount 16
#define kMinGlyphImageSize (16*2)
#define kMinAllocAmount ((sizeof(SkGlyph) + kMinGlyphImageSize) * kMinGlyphCount)
SkGlyphCache::SkGlyphCache(SkTypeface* typeface, const SkDescriptor* desc, SkScalerContext* ctx)
: fScalerContext(ctx), fGlyphAlloc(kMinAllocAmount) {
SkASSERT(typeface);
SkASSERT(desc);
SkASSERT(ctx);
fPrev = fNext = NULL;
fDesc = desc->copy();
fScalerContext->getFontMetrics(&fFontMetrics);
// init to 0 so that all of the pointers will be null
memset(fGlyphHash, 0, sizeof(fGlyphHash));
// init with 0xFF so that the charCode field will be -1, which is invalid
memset(fCharToGlyphHash, 0xFF, sizeof(fCharToGlyphHash));
fMemoryUsed = sizeof(*this);
fGlyphArray.setReserve(kMinGlyphCount);
fAuxProcList = NULL;
}
SkGlyphCache::~SkGlyphCache() {
#if 0
{
size_t ptrMem = fGlyphArray.count() * sizeof(SkGlyph*);
size_t glyphAlloc = fGlyphAlloc.totalCapacity();
size_t glyphHashUsed = 0;
size_t uniHashUsed = 0;
for (int i = 0; i < kHashCount; ++i) {
glyphHashUsed += fGlyphHash[i] ? sizeof(fGlyphHash[0]) : 0;
uniHashUsed += fCharToGlyphHash[i].fID != 0xFFFFFFFF ? sizeof(fCharToGlyphHash[0]) : 0;
}
size_t glyphUsed = fGlyphArray.count() * sizeof(SkGlyph);
size_t imageUsed = 0;
for (int i = 0; i < fGlyphArray.count(); ++i) {
const SkGlyph& g = *fGlyphArray[i];
if (g.fImage) {
imageUsed += g.fHeight * g.rowBytes();
}
}
printf("glyphPtrArray,%zu, Alloc,%zu, imageUsed,%zu, glyphUsed,%zu, glyphHashAlloc,%zu, glyphHashUsed,%zu, unicharHashAlloc,%zu, unicharHashUsed,%zu\n",
ptrMem, glyphAlloc, imageUsed, glyphUsed, sizeof(fGlyphHash), glyphHashUsed, sizeof(fCharToGlyphHash), uniHashUsed);
}
#endif
SkGlyph** gptr = fGlyphArray.begin();
SkGlyph** stop = fGlyphArray.end();
while (gptr < stop) {
SkPath* path = (*gptr)->fPath;
if (path) {
SkDELETE(path);
}
gptr += 1;
}
SkDescriptor::Free(fDesc);
SkDELETE(fScalerContext);
this->invokeAndRemoveAuxProcs();
}
///////////////////////////////////////////////////////////////////////////////
#ifdef SK_DEBUG
#define VALIDATE() AutoValidate av(this)
#else
#define VALIDATE()
#endif
uint16_t SkGlyphCache::unicharToGlyph(SkUnichar charCode) {
VALIDATE();
uint32_t id = SkGlyph::MakeID(charCode);
const CharGlyphRec& rec = fCharToGlyphHash[ID2HashIndex(id)];
if (rec.fID == id) {
return rec.fGlyph->getGlyphID();
} else {
return fScalerContext->charToGlyphID(charCode);
}
}
SkUnichar SkGlyphCache::glyphToUnichar(uint16_t glyphID) {
return fScalerContext->glyphIDToChar(glyphID);
}
unsigned SkGlyphCache::getGlyphCount() {
return fScalerContext->getGlyphCount();
}
///////////////////////////////////////////////////////////////////////////////
const SkGlyph& SkGlyphCache::getUnicharAdvance(SkUnichar charCode) {
VALIDATE();
uint32_t id = SkGlyph::MakeID(charCode);
CharGlyphRec* rec = &fCharToGlyphHash[ID2HashIndex(id)];
if (rec->fID != id) {
// this ID is based on the UniChar
rec->fID = id;
// this ID is based on the glyph index
id = SkGlyph::MakeID(fScalerContext->charToGlyphID(charCode));
rec->fGlyph = this->lookupMetrics(id, kJustAdvance_MetricsType);
}
return *rec->fGlyph;
}
const SkGlyph& SkGlyphCache::getGlyphIDAdvance(uint16_t glyphID) {
VALIDATE();
uint32_t id = SkGlyph::MakeID(glyphID);
unsigned index = ID2HashIndex(id);
SkGlyph* glyph = fGlyphHash[index];
if (NULL == glyph || glyph->fID != id) {
glyph = this->lookupMetrics(glyphID, kJustAdvance_MetricsType);
fGlyphHash[index] = glyph;
}
return *glyph;
}
///////////////////////////////////////////////////////////////////////////////
const SkGlyph& SkGlyphCache::getUnicharMetrics(SkUnichar charCode) {
VALIDATE();
uint32_t id = SkGlyph::MakeID(charCode);
CharGlyphRec* rec = &fCharToGlyphHash[ID2HashIndex(id)];
if (rec->fID != id) {
RecordHashCollisionIf(rec->fGlyph != NULL);
// this ID is based on the UniChar
rec->fID = id;
// this ID is based on the glyph index
id = SkGlyph::MakeID(fScalerContext->charToGlyphID(charCode));
rec->fGlyph = this->lookupMetrics(id, kFull_MetricsType);
} else {
RecordHashSuccess();
if (rec->fGlyph->isJustAdvance()) {
fScalerContext->getMetrics(rec->fGlyph);
}
}
SkASSERT(rec->fGlyph->isFullMetrics());
return *rec->fGlyph;
}
const SkGlyph& SkGlyphCache::getUnicharMetrics(SkUnichar charCode,
SkFixed x, SkFixed y) {
VALIDATE();
uint32_t id = SkGlyph::MakeID(charCode, x, y);
CharGlyphRec* rec = &fCharToGlyphHash[ID2HashIndex(id)];
if (rec->fID != id) {
RecordHashCollisionIf(rec->fGlyph != NULL);
// this ID is based on the UniChar
rec->fID = id;
// this ID is based on the glyph index
id = SkGlyph::MakeID(fScalerContext->charToGlyphID(charCode), x, y);
rec->fGlyph = this->lookupMetrics(id, kFull_MetricsType);
} else {
RecordHashSuccess();
if (rec->fGlyph->isJustAdvance()) {
fScalerContext->getMetrics(rec->fGlyph);
}
}
SkASSERT(rec->fGlyph->isFullMetrics());
return *rec->fGlyph;
}
const SkGlyph& SkGlyphCache::getGlyphIDMetrics(uint16_t glyphID) {
VALIDATE();
uint32_t id = SkGlyph::MakeID(glyphID);
unsigned index = ID2HashIndex(id);
SkGlyph* glyph = fGlyphHash[index];
if (NULL == glyph || glyph->fID != id) {
RecordHashCollisionIf(glyph != NULL);
glyph = this->lookupMetrics(glyphID, kFull_MetricsType);
fGlyphHash[index] = glyph;
} else {
RecordHashSuccess();
if (glyph->isJustAdvance()) {
fScalerContext->getMetrics(glyph);
}
}
SkASSERT(glyph->isFullMetrics());
return *glyph;
}
const SkGlyph& SkGlyphCache::getGlyphIDMetrics(uint16_t glyphID,
SkFixed x, SkFixed y) {
VALIDATE();
uint32_t id = SkGlyph::MakeID(glyphID, x, y);
unsigned index = ID2HashIndex(id);
SkGlyph* glyph = fGlyphHash[index];
if (NULL == glyph || glyph->fID != id) {
RecordHashCollisionIf(glyph != NULL);
glyph = this->lookupMetrics(id, kFull_MetricsType);
fGlyphHash[index] = glyph;
} else {
RecordHashSuccess();
if (glyph->isJustAdvance()) {
fScalerContext->getMetrics(glyph);
}
}
SkASSERT(glyph->isFullMetrics());
return *glyph;
}
SkGlyph* SkGlyphCache::lookupMetrics(uint32_t id, MetricsType mtype) {
SkGlyph* glyph;
int hi = 0;
int count = fGlyphArray.count();
if (count) {
SkGlyph** gptr = fGlyphArray.begin();
int lo = 0;
hi = count - 1;
while (lo < hi) {
int mid = (hi + lo) >> 1;
if (gptr[mid]->fID < id) {
lo = mid + 1;
} else {
hi = mid;
}
}
glyph = gptr[hi];
if (glyph->fID == id) {
if (kFull_MetricsType == mtype && glyph->isJustAdvance()) {
fScalerContext->getMetrics(glyph);
}
return glyph;
}
// check if we need to bump hi before falling though to the allocator
if (glyph->fID < id) {
hi += 1;
}
}
// not found, but hi tells us where to inser the new glyph
fMemoryUsed += sizeof(SkGlyph);
glyph = (SkGlyph*)fGlyphAlloc.alloc(sizeof(SkGlyph),
SkChunkAlloc::kThrow_AllocFailType);
glyph->init(id);
*fGlyphArray.insert(hi) = glyph;
if (kJustAdvance_MetricsType == mtype) {
fScalerContext->getAdvance(glyph);
} 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 (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 (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;
}
rec = rec->fNext;
}
return false;
}
void SkGlyphCache::setAuxProc(void (*proc)(void*), void* data) {
if (proc == NULL) {
return;
}
AuxProcRec* rec = fAuxProcList;
while (rec) {
if (rec->fProc == proc) {
rec->fData = data;
return;
}
rec = rec->fNext;
}
// not found, create a new rec
rec = SkNEW(AuxProcRec);
rec->fProc = proc;
rec->fData = data;
rec->fNext = fAuxProcList;
fAuxProcList = rec;
}
void SkGlyphCache::invokeAndRemoveAuxProcs() {
AuxProcRec* rec = fAuxProcList;
while (rec) {
rec->fProc(rec->fData);
AuxProcRec* next = rec->fNext;
SkDELETE(rec);
rec = next;
}
}
///////////////////////////////////////////////////////////////////////////////
///////////////////////////////////////////////////////////////////////////////
#include "SkThread.h"
size_t SkGlyphCache_Globals::setCacheSizeLimit(size_t newLimit) {
static const size_t minLimit = 256 * 1024;
if (newLimit < minLimit) {
newLimit = minLimit;
}
SkAutoMutexAcquire ac(fMutex);
size_t prevLimit = fCacheSizeLimit;
fCacheSizeLimit = newLimit;
this->internalPurge();
return prevLimit;
}
int SkGlyphCache_Globals::setCacheCountLimit(int newCount) {
if (newCount < 0) {
newCount = 0;
}
SkAutoMutexAcquire ac(fMutex);
int prevCount = fCacheCountLimit;
fCacheCountLimit = newCount;
this->internalPurge();
return prevCount;
}
void SkGlyphCache_Globals::purgeAll() {
SkAutoMutexAcquire ac(fMutex);
this->internalPurge(fTotalMemoryUsed);
}
void SkGlyphCache::VisitAllCaches(bool (*proc)(SkGlyphCache*, void*),
void* context) {
SkGlyphCache_Globals& globals = getGlobals();
SkAutoMutexAcquire ac(globals.fMutex);
SkGlyphCache* cache;
globals.validate();
for (cache = globals.internalGetHead(); cache != NULL; cache = cache->fNext) {
if (proc(cache, context)) {
break;
}
}
globals.validate();
}
/* This guy calls the visitor from within the mutext lock, so the visitor
cannot:
- take too much time
- try to acquire the mutext again
- call a fontscaler (which might call into the cache)
*/
SkGlyphCache* SkGlyphCache::VisitCache(SkTypeface* typeface,
const SkDescriptor* desc,
bool (*proc)(const SkGlyphCache*, void*),
void* context) {
if (!typeface) {
typeface = SkTypeface::GetDefaultTypeface();
}
SkASSERT(desc);
SkGlyphCache_Globals& globals = getGlobals();
SkAutoMutexAcquire ac(globals.fMutex);
SkGlyphCache* cache;
bool insideMutex = true;
globals.validate();
for (cache = globals.internalGetHead(); cache != NULL; cache = cache->fNext) {
if (cache->fDesc->equals(*desc)) {
globals.internalDetachCache(cache);
goto FOUND_IT;
}
}
/* Release the mutex now, before we create a new entry (which might have
side-effects like trying to access the cache/mutex (yikes!)
*/
ac.release(); // release the mutex now
insideMutex = false; // can't use globals anymore
// Check if we can create a scaler-context before creating the glyphcache.
// If not, we may have exhausted OS/font resources, so try purging the
// cache once and try again.
{
// pass true the first time, to notice if the scalercontext failed,
// so we can try the purge.
SkScalerContext* ctx = typeface->createScalerContext(desc, true);
if (!ctx) {
getSharedGlobals().purgeAll();
ctx = typeface->createScalerContext(desc, false);
SkASSERT(ctx);
}
cache = SkNEW_ARGS(SkGlyphCache, (typeface, desc, ctx));
}
FOUND_IT:
AutoValidate av(cache);
if (!proc(cache, context)) { // need to reattach
if (insideMutex) {
globals.internalAttachCacheToHead(cache);
} else {
globals.attachCacheToHead(cache);
}
cache = NULL;
}
return cache;
}
void SkGlyphCache::AttachCache(SkGlyphCache* cache) {
SkASSERT(cache);
SkASSERT(cache->fNext == NULL);
getGlobals().attachCacheToHead(cache);
}
///////////////////////////////////////////////////////////////////////////////
void SkGlyphCache_Globals::attachCacheToHead(SkGlyphCache* cache) {
SkAutoMutexAcquire ac(fMutex);
this->validate();
cache->validate();
this->internalAttachCacheToHead(cache);
this->internalPurge();
}
SkGlyphCache* SkGlyphCache_Globals::internalGetTail() const {
SkGlyphCache* cache = fHead;
if (cache) {
while (cache->fNext) {
cache = cache->fNext;
}
}
return cache;
}
size_t SkGlyphCache_Globals::internalPurge(size_t minBytesNeeded) {
this->validate();
size_t bytesNeeded = 0;
if (fTotalMemoryUsed > fCacheSizeLimit) {
bytesNeeded = fTotalMemoryUsed - fCacheSizeLimit;
}
bytesNeeded = SkTMax(bytesNeeded, minBytesNeeded);
if (bytesNeeded) {
// no small purges!
bytesNeeded = SkTMax(bytesNeeded, fTotalMemoryUsed >> 2);
}
int countNeeded = 0;
if (fCacheCount > fCacheCountLimit) {
countNeeded = fCacheCount - fCacheCountLimit;
// no small purges!
countNeeded = SkMax32(countNeeded, fCacheCount >> 2);
}
// early exit
if (!countNeeded && !bytesNeeded) {
return 0;
}
size_t bytesFreed = 0;
int countFreed = 0;
// we start at the tail and proceed backwards, as the linklist is in LRU
// order, with unimportant entries at the tail.
SkGlyphCache* cache = this->internalGetTail();
while (cache != NULL &&
(bytesFreed < bytesNeeded || countFreed < countNeeded)) {
SkGlyphCache* prev = cache->fPrev;
bytesFreed += cache->fMemoryUsed;
countFreed += 1;
this->internalDetachCache(cache);
SkDELETE(cache);
cache = prev;
}
this->validate();
#ifdef SPEW_PURGE_STATUS
if (countFreed) {
SkDebugf("purging %dK from font cache [%d entries]\n",
(int)(bytesFreed >> 10), countFreed);
}
#endif
return bytesFreed;
}
void SkGlyphCache_Globals::internalAttachCacheToHead(SkGlyphCache* cache) {
SkASSERT(NULL == cache->fPrev && NULL == cache->fNext);
if (fHead) {
fHead->fPrev = cache;
cache->fNext = fHead;
}
fHead = cache;
fCacheCount += 1;
fTotalMemoryUsed += cache->fMemoryUsed;
}
void SkGlyphCache_Globals::internalDetachCache(SkGlyphCache* cache) {
SkASSERT(fCacheCount > 0);
fCacheCount -= 1;
fTotalMemoryUsed -= cache->fMemoryUsed;
if (cache->fPrev) {
cache->fPrev->fNext = cache->fNext;
} else {
fHead = cache->fNext;
}
if (cache->fNext) {
cache->fNext->fPrev = cache->fPrev;
}
cache->fPrev = cache->fNext = NULL;
}
///////////////////////////////////////////////////////////////////////////////
#ifdef SK_DEBUG
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) {
computedBytes += head->fMemoryUsed;
computedCount += 1;
head = head->fNext;
}
SkASSERT(fTotalMemoryUsed == computedBytes);
SkASSERT(fCacheCount == computedCount);
}
#endif
///////////////////////////////////////////////////////////////////////////////
///////////////////////////////////////////////////////////////////////////////
#include "SkTypefaceCache.h"
size_t SkGraphics::GetFontCacheLimit() {
return getSharedGlobals().getCacheSizeLimit();
}
size_t SkGraphics::SetFontCacheLimit(size_t bytes) {
return getSharedGlobals().setCacheSizeLimit(bytes);
}
size_t SkGraphics::GetFontCacheUsed() {
return getSharedGlobals().getTotalMemoryUsed();
}
int SkGraphics::GetFontCacheCountLimit() {
return getSharedGlobals().getCacheCountLimit();
}
int SkGraphics::SetFontCacheCountLimit(int count) {
return getSharedGlobals().setCacheCountLimit(count);
}
int SkGraphics::GetFontCacheCountUsed() {
return getSharedGlobals().getCacheCountUsed();
}
void SkGraphics::PurgeFontCache() {
getSharedGlobals().purgeAll();
SkTypefaceCache::PurgeAll();
}
size_t SkGraphics::GetTLSFontCacheLimit() {
const SkGlyphCache_Globals* tls = SkGlyphCache_Globals::FindTLS();
return tls ? tls->getCacheSizeLimit() : 0;
}
void SkGraphics::SetTLSFontCacheLimit(size_t bytes) {
if (0 == bytes) {
SkGlyphCache_Globals::DeleteTLS();
} else {
SkGlyphCache_Globals::GetTLS().setCacheSizeLimit(bytes);
}
}