blob: e3927c0d1f097853ca18ba9c405c1b5c632b4f67 [file] [log] [blame]
/*
* Copyright 2012 Google Inc.
*
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
#include "GrTextureStripAtlas.h"
#include "SkPixelRef.h"
#include "SkTSearch.h"
#include "GrTexture.h"
#ifdef SK_DEBUG
#define VALIDATE this->validate()
#else
#define VALIDATE
#endif
class GrTextureStripAtlas::Hash : public SkTDynamicHash<GrTextureStripAtlas::AtlasEntry,
GrTextureStripAtlas::AtlasEntry::Key> {};
int32_t GrTextureStripAtlas::gCacheCount = 0;
GrTextureStripAtlas::Hash* GrTextureStripAtlas::gAtlasCache = NULL;
GrTextureStripAtlas::Hash* GrTextureStripAtlas::GetCache() {
if (NULL == gAtlasCache) {
gAtlasCache = SkNEW(Hash);
}
return gAtlasCache;
}
// Remove the specified atlas from the cache
void GrTextureStripAtlas::CleanUp(const GrContext*, void* info) {
SkASSERT(NULL != info);
AtlasEntry* entry = static_cast<AtlasEntry*>(info);
// remove the cache entry
GetCache()->remove(entry->fKey);
// remove the actual entry
SkDELETE(entry);
if (0 == GetCache()->count()) {
SkDELETE(gAtlasCache);
gAtlasCache = NULL;
}
}
GrTextureStripAtlas* GrTextureStripAtlas::GetAtlas(const GrTextureStripAtlas::Desc& desc) {
AtlasEntry::Key key;
key.setKeyData(desc.asKey());
AtlasEntry* entry = GetCache()->find(key);
if (NULL == entry) {
entry = SkNEW(AtlasEntry);
entry->fAtlas = SkNEW_ARGS(GrTextureStripAtlas, (desc));
entry->fKey = key;
desc.fContext->addCleanUp(CleanUp, entry);
GetCache()->add(entry);
}
return entry->fAtlas;
}
GrTextureStripAtlas::GrTextureStripAtlas(GrTextureStripAtlas::Desc desc)
: fCacheKey(sk_atomic_inc(&gCacheCount))
, fLockedRows(0)
, fDesc(desc)
, fNumRows(desc.fHeight / desc.fRowHeight)
, fTexture(NULL)
, fRows(SkNEW_ARRAY(AtlasRow, fNumRows))
, fLRUFront(NULL)
, fLRUBack(NULL) {
SkASSERT(fNumRows * fDesc.fRowHeight == fDesc.fHeight);
this->initLRU();
VALIDATE;
}
GrTextureStripAtlas::~GrTextureStripAtlas() {
SkDELETE_ARRAY(fRows);
}
int GrTextureStripAtlas::lockRow(const SkBitmap& data) {
VALIDATE;
if (0 == fLockedRows) {
this->lockTexture();
}
int key = data.getGenerationID();
int rowNumber = -1;
int index = this->searchByKey(key);
if (index >= 0) {
// We already have the data in a row, so we can just return that row
AtlasRow* row = fKeyTable[index];
if (0 == row->fLocks) {
this->removeFromLRU(row);
}
++row->fLocks;
++fLockedRows;
// Since all the rows are always stored in a contiguous array, we can save the memory
// required for storing row numbers and just compute it with some pointer arithmetic
rowNumber = static_cast<int>(row - fRows);
} else {
// ~index is the index where we will insert the new key to keep things sorted
index = ~index;
// We don't have this data cached, so pick the least recently used row to copy into
AtlasRow* row = this->getLRU();
++fLockedRows;
if (NULL == row) {
// force a flush, which should unlock all the rows; then try again
fDesc.fContext->flush();
row = this->getLRU();
if (NULL == row) {
--fLockedRows;
return -1;
}
}
this->removeFromLRU(row);
uint32_t oldKey = row->fKey;
// If we are writing into a row that already held bitmap data, we need to remove the
// reference to that genID which is stored in our sorted table of key values.
if (oldKey != kEmptyAtlasRowKey) {
// Find the entry in the list; if it's before the index where we plan on adding the new
// entry, we decrement since it will shift elements ahead of it back by one.
int oldIndex = this->searchByKey(oldKey);
if (oldIndex < index) {
--index;
}
fKeyTable.remove(oldIndex);
}
row->fKey = key;
row->fLocks = 1;
fKeyTable.insert(index, 1, &row);
rowNumber = static_cast<int>(row - fRows);
SkAutoLockPixels lock(data);
// Pass in the kDontFlush flag, since we know we're writing to a part of this texture
// that is not currently in use
fDesc.fContext->writeTexturePixels(fTexture,
0, rowNumber * fDesc.fRowHeight,
fDesc.fWidth, fDesc.fRowHeight,
SkImageInfo2GrPixelConfig(data.info()),
data.getPixels(),
data.rowBytes(),
GrContext::kDontFlush_PixelOpsFlag);
}
SkASSERT(rowNumber >= 0);
VALIDATE;
return rowNumber;
}
void GrTextureStripAtlas::unlockRow(int row) {
VALIDATE;
--fRows[row].fLocks;
--fLockedRows;
SkASSERT(fRows[row].fLocks >= 0 && fLockedRows >= 0);
if (0 == fRows[row].fLocks) {
this->appendLRU(fRows + row);
}
if (0 == fLockedRows) {
this->unlockTexture();
}
VALIDATE;
}
GrTextureStripAtlas::AtlasRow* GrTextureStripAtlas::getLRU() {
// Front is least-recently-used
AtlasRow* row = fLRUFront;
return row;
}
void GrTextureStripAtlas::lockTexture() {
GrTextureParams params;
GrTextureDesc texDesc;
texDesc.fWidth = fDesc.fWidth;
texDesc.fHeight = fDesc.fHeight;
texDesc.fConfig = fDesc.fConfig;
static const GrCacheID::Domain gTextureStripAtlasDomain = GrCacheID::GenerateDomain();
GrCacheID::Key key;
*key.fData32 = fCacheKey;
memset(key.fData32 + 1, 0, sizeof(key) - sizeof(uint32_t));
GrCacheID cacheID(gTextureStripAtlasDomain, key);
fTexture = fDesc.fContext->findAndRefTexture(texDesc, cacheID, &params);
if (NULL == fTexture) {
fTexture = fDesc.fContext->createTexture(&params, texDesc, cacheID, NULL, 0);
// This is a new texture, so all of our cache info is now invalid
this->initLRU();
fKeyTable.rewind();
}
SkASSERT(NULL != fTexture);
}
void GrTextureStripAtlas::unlockTexture() {
SkASSERT(NULL != fTexture && 0 == fLockedRows);
fTexture->unref();
fTexture = NULL;
fDesc.fContext->purgeCache();
}
void GrTextureStripAtlas::initLRU() {
fLRUFront = NULL;
fLRUBack = NULL;
// Initially all the rows are in the LRU list
for (int i = 0; i < fNumRows; ++i) {
fRows[i].fKey = kEmptyAtlasRowKey;
fRows[i].fNext = NULL;
fRows[i].fPrev = NULL;
this->appendLRU(fRows + i);
}
SkASSERT(NULL == fLRUFront || NULL == fLRUFront->fPrev);
SkASSERT(NULL == fLRUBack || NULL == fLRUBack->fNext);
}
void GrTextureStripAtlas::appendLRU(AtlasRow* row) {
SkASSERT(NULL == row->fPrev && NULL == row->fNext);
if (NULL == fLRUFront && NULL == fLRUBack) {
fLRUFront = row;
fLRUBack = row;
} else {
row->fPrev = fLRUBack;
fLRUBack->fNext = row;
fLRUBack = row;
}
}
void GrTextureStripAtlas::removeFromLRU(AtlasRow* row) {
SkASSERT(NULL != row);
if (NULL != row->fNext && NULL != row->fPrev) {
row->fPrev->fNext = row->fNext;
row->fNext->fPrev = row->fPrev;
} else {
if (NULL == row->fNext) {
SkASSERT(row == fLRUBack);
fLRUBack = row->fPrev;
if (fLRUBack) {
fLRUBack->fNext = NULL;
}
}
if (NULL == row->fPrev) {
SkASSERT(row == fLRUFront);
fLRUFront = row->fNext;
if (fLRUFront) {
fLRUFront->fPrev = NULL;
}
}
}
row->fNext = NULL;
row->fPrev = NULL;
}
int GrTextureStripAtlas::searchByKey(uint32_t key) {
AtlasRow target;
target.fKey = key;
return SkTSearch<const AtlasRow,
GrTextureStripAtlas::KeyLess>((const AtlasRow**)fKeyTable.begin(),
fKeyTable.count(),
&target,
sizeof(AtlasRow*));
}
#ifdef SK_DEBUG
void GrTextureStripAtlas::validate() {
// Our key table should be sorted
uint32_t prev = 1 > fKeyTable.count() ? 0 : fKeyTable[0]->fKey;
for (int i = 1; i < fKeyTable.count(); ++i) {
SkASSERT(prev < fKeyTable[i]->fKey);
SkASSERT(fKeyTable[i]->fKey != kEmptyAtlasRowKey);
prev = fKeyTable[i]->fKey;
}
int lruCount = 0;
// Validate LRU pointers, and count LRU entries
SkASSERT(NULL == fLRUFront || NULL == fLRUFront->fPrev);
SkASSERT(NULL == fLRUBack || NULL == fLRUBack->fNext);
for (AtlasRow* r = fLRUFront; r != NULL; r = r->fNext) {
if (NULL == r->fNext) {
SkASSERT(r == fLRUBack);
} else {
SkASSERT(r->fNext->fPrev == r);
}
++lruCount;
}
int rowLocks = 0;
int freeRows = 0;
for (int i = 0; i < fNumRows; ++i) {
rowLocks += fRows[i].fLocks;
if (0 == fRows[i].fLocks) {
++freeRows;
bool inLRU = false;
// Step through the LRU and make sure it's present
for (AtlasRow* r = fLRUFront; r != NULL; r = r->fNext) {
if (r == &fRows[i]) {
inLRU = true;
break;
}
}
SkASSERT(inLRU);
} else {
// If we are locked, we should have a key
SkASSERT(kEmptyAtlasRowKey != fRows[i].fKey);
}
// If we have a key != kEmptyAtlasRowKey, it should be in the key table
SkASSERT(fRows[i].fKey == kEmptyAtlasRowKey || this->searchByKey(fRows[i].fKey) >= 0);
}
// Our count of locks should equal the sum of row locks, unless we ran out of rows and flushed,
// in which case we'll have one more lock than recorded in the rows (to represent the pending
// lock of a row; which ensures we don't unlock the texture prematurely).
SkASSERT(rowLocks == fLockedRows || rowLocks + 1 == fLockedRows);
// We should have one lru entry for each free row
SkASSERT(freeRows == lruCount);
// If we have locked rows, we should have a locked texture, otherwise
// it should be unlocked
if (fLockedRows == 0) {
SkASSERT(NULL == fTexture);
} else {
SkASSERT(NULL != fTexture);
}
}
#endif