Method BeginQuery

Source/Engine/GraphicsDevice/Vulkan/GPUContextVulkan.cpp:1316–1355

}

uint64 GPUContextVulkan::BeginQuery(GPUQueryType type)
{
    // Check if timer queries are supported
    if (type == GPUQueryType::Timer && _device->PhysicalDeviceLimits.timestampComputeAndGraphics != VK_TRUE)
        return 0;

    // Allocate query
    auto poolIndex = _device->GetOrCreateQueryPool(type);
    auto pool = _device->QueryPools[poolIndex];
    uint32 index = 0;
    const auto cmdBuffer = _cmdBufferManager->GetCmdBuffer();
    if (!pool->AcquireQuery(cmdBuffer, index))
        return 0;
    GPUQueryVulkan query;
    query.PoolIndex = (uint16)poolIndex;
    query.QueryIndex = (uint16)index;
    query.SecondQueryIndex = 0;
    query.Dummy = 1; // Ensure Raw is never 0, even for the first query

    // Begin query
    switch (type)
    {
    case GPUQueryType::Timer:
        // Timer queries need 2 slots (begin + end)
        pool->AcquireQuery(cmdBuffer, index);
        query.SecondQueryIndex = (uint16)index;

        vkCmdWriteTimestamp(cmdBuffer->GetHandle(), VK_PIPELINE_STAGE_TOP_OF_PIPE_BIT, pool->GetHandle(), query.QueryIndex);
#if GPU_VULKAN_PAUSE_QUERIES
        _cmdBufferManager->OnTimerQueryBegin(query.Raw);
#endif
        break;
    case GPUQueryType::Occlusion:
        vkCmdBeginQuery(cmdBuffer->GetHandle(), pool->GetHandle(), query.QueryIndex, 0);
        break;
    }
    pool->MarkQueryAsStarted(query.QueryIndex);

    return query.Raw;
}

void GPUContextVulkan::EndQuery(uint64 queryID)
{