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SAGA2: Fix crash because of fetchPlatform

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a/ 2021-06-13 23:06:45 +09:00 committed by Eugene Sandulenko
parent c4071bc8e9
commit 8833b47fe4
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1 changed files with 46 additions and 63 deletions
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109
engines/saga2/tile.cpp
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@ -2273,8 +2273,6 @@ static void readPlatform(hResContext *con, Platform &plt) {
}
Platform *MetaTile::fetchPlatform(int16 mapNum, int16 layer) {
const int cacheFlag = 0x8000;
uint16 plIndex = stack[layer];
PlatformCacheEntry *pce;
@ -2286,73 +2284,41 @@ Platform *MetaTile::fetchPlatform(int16 mapNum, int16 layer) {
if (plIndex == nullID) {
return nullptr;
}
// if platform in cache
else if (plIndex & cacheFlag) {
plIndex &= ~cacheFlag;
assert(plIndex < platformCacheSize);
int cacheIndex;
// Get the address of the pce from the cache
pce = &platformCache[plIndex];
// Since the platform is not in the cache, we need to
// dump something from the cache. Dump the one that
// was least recently used.
// Get head of LRU chain.
pce = (PlatformCacheEntry *)platformLRU.remHead();
platformLRU.addTail(*pce);
assert(pce->platformNum >= 0);
assert(pce->metaID != NoMetaTile);
assert(pce->metaID == thisID(mapNum));
// Compute the layer of this entry in the cache
cacheIndex = pce - platformCache;
assert(cacheIndex < platformCacheSize);
assert(cacheIndex >= 0);
// Move to the end of the LRU
pce->remove();
platformLRU.addTail(*pce);
// Initialize the cache entry to the new platform data.
pce->platformNum = plIndex;
pce->layerNum = layer;
pce->metaID = thisID(mapNum);
stack[layer] = (cacheIndex);
// return the address of the platform
return &pce->pl;
}
// if platform not in memory
else {
int cacheIndex;
assert(plIndex >= 0);
assert(plIndex * sizeof(Platform) < tileRes->size(platformID + MKTAG(0, 0, 0, mapNum)));
debug(3, "plIndex: %d", plIndex);
// Since the platform is not in the cache, we need to
// dump something from the cache. Dump the one that
// was least recently used.
// Get head of LRU chain.
pce = (PlatformCacheEntry *)platformLRU.remHead();
platformLRU.addTail(*pce);
// Compute the layer of this entry in the cache
cacheIndex = pce - platformCache;
assert(cacheIndex < platformCacheSize);
assert(cacheIndex >= 0);
// Now, flush the old mt from the cache.
// This assumes that all metatiles from all worlds are loaded.
if (pce->metaID != NoMetaTile) {
MetaTile *oldMeta = metaTileAddress(pce->metaID);
assert(pce->layerNum < maxPlatforms);
assert(oldMeta->stack[pce->layerNum] == (cacheFlag | cacheIndex));
oldMeta->stack[pce->layerNum] = pce->platformNum;
// Now, load the actual metatile data...
if (tileRes->seek(platformID + MKTAG(0, 0, 0, mapNum))) {
if (tileRes->skip(plIndex * sizeof(Platform))) {
readPlatform(tileRes, pce->pl);
return &pce->pl;
}
// Initialize the cache entry to the new platform data.
pce->platformNum = plIndex;
pce->layerNum = layer;
pce->metaID = thisID(mapNum);
stack[layer] = (cacheFlag | cacheIndex);
assert(plIndex >= 0);
assert(plIndex * sizeof(Platform) < tileRes->size(platformID + MKTAG(0, 0, 0, mapNum)));
// Now, load the actual metatile data...
if (tileRes->seek(platformID + MKTAG(0, 0, 0, mapNum))) {
if (tileRes->skip(plIndex * sizeof(Platform))) {
readPlatform(tileRes, pce->pl);
return &pce->pl;
}
}
error("Unable to read Platform %d of map %d", plIndex, mapNum);
return nullptr;
}
error("Unable to read Platform %d of map %d", plIndex, mapNum);
return nullptr;
}
//-----------------------------------------------------------------------
@ -4376,12 +4342,29 @@ struct TileCycleArchive {
//-----------------------------------------------------------------------
// Initialize the tile cycling state array
static void readCycle(hResContext *con, TileCycleData &cyc) {
cyc.counter = con->readS32LE();
cyc.pad = con->readByte();
cyc.numStates = con->readByte();
cyc.currentState = con->readByte();
cyc.cycleSpeed = con->readByte();
for (int i = 0; i < 16; ++i)
cyc.cycleList[i] = con->readU16LE();
}
void initTileCyclingStates(void) {
cycleList = (CyclePtr)LoadResource(tileRes, cycleID, "tile cycle data");
const int tileCycleDataSize = 40;
cycleCount = tileRes->size(cycleID) / tileCycleDataSize;
cycleList = new TileCycleData[cycleCount];
tileRes->seek(cycleID);
for (int i = 0; i < cycleCount; ++i)
readCycle(tileRes, cycleList[i]);
if (cycleList == nullptr)
error("Unable to load tile cycling data");
cycleCount = tileRes->size(cycleID) / sizeof(TileCycleData);
}
//-----------------------------------------------------------------------