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Cart: Improved mirroring logic for games that aren't a power of 2 in size

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Sour 2019-04-02 18:24:28 -04:00
parent f1cbbb02f5
commit 5a006d6ff8
1 changed files with 14 additions and 0 deletions
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14
Core/BaseCartridge.cpp
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@ -229,6 +229,20 @@ void BaseCartridge::RegisterHandlers(MemoryManager &mm)
_prgRomHandlers.push_back(unique_ptr<RomHandler>(new RomHandler(_prgRom, i, _prgRomSize, SnesMemoryType::PrgRom)));
}
uint32_t power = (uint32_t)std::log2(_prgRomSize);
if(_prgRomSize > (1 << power)) {
//If size isn't a power of 2, mirror the part above the nearest (lower) power of 2 until the size reaches the next power of 2.
uint32_t halfSize = 1 << power;
uint32_t fullSize = 1 << (power + 1);
uint32_t extraSize = _prgRomSize - halfSize;
while(_prgRomHandlers.size() < fullSize / 0x1000) {
for(uint32_t i = 0; i < extraSize / 0x1000; i += 0x1000) {
_prgRomHandlers.push_back(unique_ptr<RomHandler>(new RomHandler(_prgRom, halfSize + i, _prgRomSize, SnesMemoryType::PrgRom)));
}
}
}
for(uint32_t i = 0; i < _saveRamSize; i += 0x1000) {
_saveRamHandlers.push_back(unique_ptr<RamHandler>(new RamHandler(_saveRam, i, _saveRamSize, SnesMemoryType::SaveRam)));
}