GrTextureStripAtlas.cpp revision 6bfef2dfec3253efa48aec0b5ea108e0dc041d15
1 2/* 3 * Copyright 2012 Google Inc. 4 * 5 * Use of this source code is governed by a BSD-style license that can be 6 * found in the LICENSE file. 7 */ 8 9#include "GrTextureStripAtlas.h" 10#include "SkPixelRef.h" 11#include "SkTSearch.h" 12#include "GrTexture.h" 13 14#ifdef SK_DEBUG 15 #define VALIDATE this->validate() 16#else 17 #define VALIDATE 18#endif 19 20class GrTextureStripAtlas::Hash : public SkTDynamicHash<GrTextureStripAtlas::AtlasEntry, 21 GrTextureStripAtlas::AtlasEntry::Key> {}; 22 23int32_t GrTextureStripAtlas::gCacheCount = 0; 24 25GrTextureStripAtlas::Hash* GrTextureStripAtlas::gAtlasCache = NULL; 26 27GrTextureStripAtlas::Hash* GrTextureStripAtlas::GetCache() { 28 29 if (NULL == gAtlasCache) { 30 gAtlasCache = SkNEW(Hash); 31 } 32 33 return gAtlasCache; 34} 35 36// Remove the specified atlas from the cache 37void GrTextureStripAtlas::CleanUp(const GrContext*, void* info) { 38 SkASSERT(info); 39 40 AtlasEntry* entry = static_cast<AtlasEntry*>(info); 41 42 // remove the cache entry 43 GetCache()->remove(entry->fKey); 44 45 // remove the actual entry 46 SkDELETE(entry); 47 48 if (0 == GetCache()->count()) { 49 SkDELETE(gAtlasCache); 50 gAtlasCache = NULL; 51 } 52} 53 54GrTextureStripAtlas* GrTextureStripAtlas::GetAtlas(const GrTextureStripAtlas::Desc& desc) { 55 AtlasEntry::Key key; 56 key.setKeyData(desc.asKey()); 57 AtlasEntry* entry = GetCache()->find(key); 58 if (NULL == entry) { 59 entry = SkNEW(AtlasEntry); 60 61 entry->fAtlas = SkNEW_ARGS(GrTextureStripAtlas, (desc)); 62 entry->fKey = key; 63 64 desc.fContext->addCleanUp(CleanUp, entry); 65 66 GetCache()->add(entry); 67 } 68 69 return entry->fAtlas; 70} 71 72GrTextureStripAtlas::GrTextureStripAtlas(GrTextureStripAtlas::Desc desc) 73 : fCacheKey(sk_atomic_inc(&gCacheCount)) 74 , fLockedRows(0) 75 , fDesc(desc) 76 , fNumRows(desc.fHeight / desc.fRowHeight) 77 , fTexture(NULL) 78 , fRows(SkNEW_ARRAY(AtlasRow, fNumRows)) 79 , fLRUFront(NULL) 80 , fLRUBack(NULL) { 81 SkASSERT(fNumRows * fDesc.fRowHeight == fDesc.fHeight); 82 this->initLRU(); 83 fNormalizedYHeight = SK_Scalar1 / fDesc.fHeight; 84 VALIDATE; 85} 86 87GrTextureStripAtlas::~GrTextureStripAtlas() { 88 SkDELETE_ARRAY(fRows); 89} 90 91int GrTextureStripAtlas::lockRow(const SkBitmap& data) { 92 VALIDATE; 93 if (0 == fLockedRows) { 94 this->lockTexture(); 95 } 96 97 int key = data.getGenerationID(); 98 int rowNumber = -1; 99 int index = this->searchByKey(key); 100 101 if (index >= 0) { 102 // We already have the data in a row, so we can just return that row 103 AtlasRow* row = fKeyTable[index]; 104 if (0 == row->fLocks) { 105 this->removeFromLRU(row); 106 } 107 ++row->fLocks; 108 ++fLockedRows; 109 110 // Since all the rows are always stored in a contiguous array, we can save the memory 111 // required for storing row numbers and just compute it with some pointer arithmetic 112 rowNumber = static_cast<int>(row - fRows); 113 } else { 114 // ~index is the index where we will insert the new key to keep things sorted 115 index = ~index; 116 117 // We don't have this data cached, so pick the least recently used row to copy into 118 AtlasRow* row = this->getLRU(); 119 120 ++fLockedRows; 121 122 if (NULL == row) { 123 // force a flush, which should unlock all the rows; then try again 124 fDesc.fContext->flush(); 125 row = this->getLRU(); 126 if (NULL == row) { 127 --fLockedRows; 128 return -1; 129 } 130 } 131 132 this->removeFromLRU(row); 133 134 uint32_t oldKey = row->fKey; 135 136 // If we are writing into a row that already held bitmap data, we need to remove the 137 // reference to that genID which is stored in our sorted table of key values. 138 if (oldKey != kEmptyAtlasRowKey) { 139 140 // Find the entry in the list; if it's before the index where we plan on adding the new 141 // entry, we decrement since it will shift elements ahead of it back by one. 142 int oldIndex = this->searchByKey(oldKey); 143 if (oldIndex < index) { 144 --index; 145 } 146 147 fKeyTable.remove(oldIndex); 148 } 149 150 row->fKey = key; 151 row->fLocks = 1; 152 fKeyTable.insert(index, 1, &row); 153 rowNumber = static_cast<int>(row - fRows); 154 155 SkAutoLockPixels lock(data); 156 157 // Pass in the kDontFlush flag, since we know we're writing to a part of this texture 158 // that is not currently in use 159 fTexture->writePixels(0, rowNumber * fDesc.fRowHeight, 160 fDesc.fWidth, fDesc.fRowHeight, 161 SkImageInfo2GrPixelConfig(data.info()), 162 data.getPixels(), 163 data.rowBytes(), 164 GrContext::kDontFlush_PixelOpsFlag); 165 } 166 167 SkASSERT(rowNumber >= 0); 168 VALIDATE; 169 return rowNumber; 170} 171 172void GrTextureStripAtlas::unlockRow(int row) { 173 VALIDATE; 174 --fRows[row].fLocks; 175 --fLockedRows; 176 SkASSERT(fRows[row].fLocks >= 0 && fLockedRows >= 0); 177 if (0 == fRows[row].fLocks) { 178 this->appendLRU(fRows + row); 179 } 180 if (0 == fLockedRows) { 181 this->unlockTexture(); 182 } 183 VALIDATE; 184} 185 186GrTextureStripAtlas::AtlasRow* GrTextureStripAtlas::getLRU() { 187 // Front is least-recently-used 188 AtlasRow* row = fLRUFront; 189 return row; 190} 191 192void GrTextureStripAtlas::lockTexture() { 193 GrTextureParams params; 194 GrSurfaceDesc texDesc; 195 texDesc.fWidth = fDesc.fWidth; 196 texDesc.fHeight = fDesc.fHeight; 197 texDesc.fConfig = fDesc.fConfig; 198 199 static const GrContentKey::Domain kDomain = GrContentKey::GenerateDomain(); 200 GrContentKey key; 201 GrContentKey::Builder builder(&key, kDomain, 1); 202 builder[0] = static_cast<uint32_t>(fCacheKey); 203 builder.finish(); 204 205 fTexture = fDesc.fContext->findAndRefTexture(texDesc, key, ¶ms); 206 if (NULL == fTexture) { 207 fTexture = fDesc.fContext->createTexture(¶ms, texDesc, key, NULL, 0); 208 // This is a new texture, so all of our cache info is now invalid 209 this->initLRU(); 210 fKeyTable.rewind(); 211 } 212 SkASSERT(fTexture); 213} 214 215void GrTextureStripAtlas::unlockTexture() { 216 SkASSERT(fTexture && 0 == fLockedRows); 217 fTexture->unref(); 218 fTexture = NULL; 219} 220 221void GrTextureStripAtlas::initLRU() { 222 fLRUFront = NULL; 223 fLRUBack = NULL; 224 // Initially all the rows are in the LRU list 225 for (int i = 0; i < fNumRows; ++i) { 226 fRows[i].fKey = kEmptyAtlasRowKey; 227 fRows[i].fNext = NULL; 228 fRows[i].fPrev = NULL; 229 this->appendLRU(fRows + i); 230 } 231 SkASSERT(NULL == fLRUFront || NULL == fLRUFront->fPrev); 232 SkASSERT(NULL == fLRUBack || NULL == fLRUBack->fNext); 233} 234 235void GrTextureStripAtlas::appendLRU(AtlasRow* row) { 236 SkASSERT(NULL == row->fPrev && NULL == row->fNext); 237 if (NULL == fLRUFront && NULL == fLRUBack) { 238 fLRUFront = row; 239 fLRUBack = row; 240 } else { 241 row->fPrev = fLRUBack; 242 fLRUBack->fNext = row; 243 fLRUBack = row; 244 } 245} 246 247void GrTextureStripAtlas::removeFromLRU(AtlasRow* row) { 248 SkASSERT(row); 249 if (row->fNext && row->fPrev) { 250 row->fPrev->fNext = row->fNext; 251 row->fNext->fPrev = row->fPrev; 252 } else { 253 if (NULL == row->fNext) { 254 SkASSERT(row == fLRUBack); 255 fLRUBack = row->fPrev; 256 if (fLRUBack) { 257 fLRUBack->fNext = NULL; 258 } 259 } 260 if (NULL == row->fPrev) { 261 SkASSERT(row == fLRUFront); 262 fLRUFront = row->fNext; 263 if (fLRUFront) { 264 fLRUFront->fPrev = NULL; 265 } 266 } 267 } 268 row->fNext = NULL; 269 row->fPrev = NULL; 270} 271 272int GrTextureStripAtlas::searchByKey(uint32_t key) { 273 AtlasRow target; 274 target.fKey = key; 275 return SkTSearch<const AtlasRow, 276 GrTextureStripAtlas::KeyLess>((const AtlasRow**)fKeyTable.begin(), 277 fKeyTable.count(), 278 &target, 279 sizeof(AtlasRow*)); 280} 281 282#ifdef SK_DEBUG 283void GrTextureStripAtlas::validate() { 284 285 // Our key table should be sorted 286 uint32_t prev = 1 > fKeyTable.count() ? 0 : fKeyTable[0]->fKey; 287 for (int i = 1; i < fKeyTable.count(); ++i) { 288 SkASSERT(prev < fKeyTable[i]->fKey); 289 SkASSERT(fKeyTable[i]->fKey != kEmptyAtlasRowKey); 290 prev = fKeyTable[i]->fKey; 291 } 292 293 int lruCount = 0; 294 // Validate LRU pointers, and count LRU entries 295 SkASSERT(NULL == fLRUFront || NULL == fLRUFront->fPrev); 296 SkASSERT(NULL == fLRUBack || NULL == fLRUBack->fNext); 297 for (AtlasRow* r = fLRUFront; r != NULL; r = r->fNext) { 298 if (NULL == r->fNext) { 299 SkASSERT(r == fLRUBack); 300 } else { 301 SkASSERT(r->fNext->fPrev == r); 302 } 303 ++lruCount; 304 } 305 306 int rowLocks = 0; 307 int freeRows = 0; 308 309 for (int i = 0; i < fNumRows; ++i) { 310 rowLocks += fRows[i].fLocks; 311 if (0 == fRows[i].fLocks) { 312 ++freeRows; 313 bool inLRU = false; 314 // Step through the LRU and make sure it's present 315 for (AtlasRow* r = fLRUFront; r != NULL; r = r->fNext) { 316 if (r == &fRows[i]) { 317 inLRU = true; 318 break; 319 } 320 } 321 SkASSERT(inLRU); 322 } else { 323 // If we are locked, we should have a key 324 SkASSERT(kEmptyAtlasRowKey != fRows[i].fKey); 325 } 326 327 // If we have a key != kEmptyAtlasRowKey, it should be in the key table 328 SkASSERT(fRows[i].fKey == kEmptyAtlasRowKey || this->searchByKey(fRows[i].fKey) >= 0); 329 } 330 331 // Our count of locks should equal the sum of row locks, unless we ran out of rows and flushed, 332 // in which case we'll have one more lock than recorded in the rows (to represent the pending 333 // lock of a row; which ensures we don't unlock the texture prematurely). 334 SkASSERT(rowLocks == fLockedRows || rowLocks + 1 == fLockedRows); 335 336 // We should have one lru entry for each free row 337 SkASSERT(freeRows == lruCount); 338 339 // If we have locked rows, we should have a locked texture, otherwise 340 // it should be unlocked 341 if (fLockedRows == 0) { 342 SkASSERT(NULL == fTexture); 343 } else { 344 SkASSERT(fTexture); 345 } 346} 347#endif 348