Decided to always use a 64-bit chunk key, rather than trying to make it configurable.

This commit is contained in:
David Williams
2015-03-20 23:09:38 +01:00
parent 6419c5827b
commit 69f6f4ac37
3 changed files with 17 additions and 19 deletions

View File

@ -284,17 +284,17 @@ namespace PolyVox
struct ChunkKey
{
ChunkKey(int32_t x, int32_t y, int32_t z) : iZPos(z), iYPos(y), iXPos(x), iValid(~0) {}
PagedVolumeChunkKeyIntType iZPos : 10;
PagedVolumeChunkKeyIntType iYPos : 10;
PagedVolumeChunkKeyIntType iXPos : 10;
int64_t iZPos : 10;
int64_t iYPos : 10;
int64_t iXPos : 10;
// Should only be true when the last access chunk pointer is valid,
// so we don't need to have a seperate check for that before using it.
PagedVolumeChunkKeyIntType iValid : 2;
int64_t iValid : 2;
};
static_assert(sizeof(ChunkKey) == sizeof(PagedVolumeChunkKeyIntType), "");
static_assert(sizeof(ChunkKey) == sizeof(int64_t), "");
PagedVolumeChunkKeyIntType posToChunkKey(int32_t iXPos, int32_t iYPos, int32_t iZPos) const
int64_t posToChunkKey(int32_t iXPos, int32_t iYPos, int32_t iZPos) const
{
iXPos = iXPos >> m_uChunkSideLengthPower;
iYPos = iYPos >> m_uChunkSideLengthPower;
@ -306,22 +306,22 @@ namespace PolyVox
// In general, bit shifting signed integers is dubious because of potential undefined or implementation defied behaviour.
// However, it seems that in practice most compilers and architectures work in the same way (http://stackoverflow.com/a/6488645).
static_assert((int32_t(-3) / 4) == 0, "fdfs");
static_assert((int32_t(-3) >> 2) == -1, "fdfs");
static_assert((int64_t(-3) / 4) == 0, "fdfs");
static_assert((int64_t(-3) >> 2) == -1, "fdfs");
/*chunkKey.iXPos = iXPos;
chunkKey.iYPos = iYPos;
chunkKey.iZPos = iZPos;*/
// If this kind of casting ever causes problems there are
// other solutions here: http://stackoverflow.com/a/2468738
PagedVolumeChunkKeyIntType iKeyAsInt32 = force_cast<PagedVolumeChunkKeyIntType>(chunkKey);
int64_t iKeyAsInt64 = force_cast<int64_t>(chunkKey);
return iKeyAsInt32;
return iKeyAsInt64;
}
Chunk* getChunk(PagedVolumeChunkKeyIntType iKeyAsInt32) const;
Chunk* getChunk(int64_t iKeyAsInt32) const;
mutable PagedVolumeChunkKeyIntType m_v3dLastAccessedChunkKey = 0;
mutable int64_t m_v3dLastAccessedChunkKey = 0;
mutable Chunk* m_pLastAccessedChunk = nullptr;
mutable std::unordered_map<uint32_t, std::unique_ptr< Chunk > > m_mapChunks;