Method ComputeDefragmentation_Extensive

include/vk_mem_alloc.h:12665–12853

}

bool VmaDefragmentationContext_T::ComputeDefragmentation_Extensive(VmaBlockVector& vector, size_t index)
{
    // First free single block, then populate it to the brim, then free another block, and so on

    // Fallback to previous algorithm since without granularity conflicts it can achieve max packing
    if (vector.m_BufferImageGranularity == 1)
        return ComputeDefragmentation_Full(vector);

    VMA_ASSERT(m_AlgorithmState != VMA_NULL);

    StateExtensive& vectorState = reinterpret_cast<StateExtensive*>(m_AlgorithmState)[index];

    bool texturePresent = false;
    bool bufferPresent = false;
    bool otherPresent = false;
    switch (vectorState.operation)
    {
    case StateExtensive::Operation::Done: // Vector defragmented
        return false;
    case StateExtensive::Operation::FindFreeBlockBuffer:
    case StateExtensive::Operation::FindFreeBlockTexture:
    case StateExtensive::Operation::FindFreeBlockAll:
    {
        // No more blocks to free, just perform fast realloc and move to cleanup
        if (vectorState.firstFreeBlock == 0)
        {
            vectorState.operation = StateExtensive::Operation::Cleanup;
            return ComputeDefragmentation_Fast(vector);
        }

        // No free blocks, have to clear last one
        size_t last = (vectorState.firstFreeBlock == SIZE_MAX ? vector.GetBlockCount() : vectorState.firstFreeBlock) - 1;
        VmaBlockMetadata* freeMetadata = vector.GetBlock(last)->m_pMetadata;

        const size_t prevMoveCount = m_Moves.size();
        for (VmaAllocHandle handle = freeMetadata->GetAllocationListBegin();
            handle != VK_NULL_HANDLE;
            handle = freeMetadata->GetNextAllocation(handle))
        {
            MoveAllocationData moveData = GetMoveData(handle, freeMetadata);
            switch (CheckCounters(moveData.move.srcAllocation->GetSize()))
            {
            case CounterStatus::Ignore:
                continue;
            case CounterStatus::End:
                return true;
            case CounterStatus::Pass:
                break;
            default:
                VMA_ASSERT(0);
            }

            // Check all previous blocks for free space
            if (AllocInOtherBlock(0, last, moveData, vector))
            {
                // Full clear performed already
                if (prevMoveCount != m_Moves.size() && freeMetadata->GetNextAllocation(handle) == VK_NULL_HANDLE)
                    vectorState.firstFreeBlock = last;