OrdinaryMagician/vkdoom_m
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Create up to 32 bottom level acceleration structures to avoid rebuilding the entire map on geometry changes

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This commit is contained in:
Magnus Norddahl 2024-08-30 03:12:24 +02:00
commit 3cb2b31d95
2 changed files with 74 additions and 36 deletions
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98
src/common/rendering/vulkan/vk_levelmesh.cpp
View file

@ -58,9 +58,13 @@ void VkLevelMesh::Reset()
deletelist->Add(std::move(LightBuffer));
deletelist->Add(std::move(LightIndexBuffer));
deletelist->Add(std::move(DrawIndexBuffer));
deletelist->Add(std::move(DynamicBLAS.ScratchBuffer));
deletelist->Add(std::move(DynamicBLAS.AccelStructBuffer));
deletelist->Add(std::move(DynamicBLAS.AccelStruct));
for (BLAS& blas : DynamicBLAS)
{
deletelist->Add(std::move(blas.ScratchBuffer));
deletelist->Add(std::move(blas.AccelStructBuffer));
deletelist->Add(std::move(blas.AccelStruct));
}
DynamicBLAS.clear();
deletelist->Add(std::move(TopLevelAS.TransferBuffer));
deletelist->Add(std::move(TopLevelAS.InstanceBuffer));
deletelist->Add(std::move(TopLevelAS.ScratchBuffer));
@ -81,9 +85,20 @@ void VkLevelMesh::CreateVulkanObjects()
.AddMemory(VK_ACCESS_TRANSFER_WRITE_BIT, VK_ACCESS_ACCELERATION_STRUCTURE_READ_BIT_KHR | VK_ACCESS_SHADER_READ_BIT)
.Execute(fb->GetCommands()->GetTransferCommands(), VK_PIPELINE_STAGE_TRANSFER_BIT, VK_PIPELINE_STAGE_ACCELERATION_STRUCTURE_BUILD_BIT_KHR | VK_PIPELINE_STAGE_FRAGMENT_SHADER_BIT);
DynamicBLAS = CreateBLAS(true, 0, Mesh->Mesh.IndexCount);
CreateTLASInstanceBuffer();
// Find out how many segments we should split the map into
DynamicBLAS.resize(32); // fb->GetDevice()->PhysicalDevice.Properties.AccelerationStructure.maxInstanceCount is 65 or 382 on current devices (aug 2024)
IndexesPerBLAS = ((Mesh->Mesh.Indexes.size() + 2) / 3 / DynamicBLAS.size() + 1) * 3;
InstanceCount = (Mesh->Mesh.IndexCount + IndexesPerBLAS - 1) / IndexesPerBLAS;
// Create a BLAS for each segment in use
for (int instance = 0; instance < InstanceCount; instance++)
{
int indexStart = instance * IndexesPerBLAS;
int indexEnd = std::min(indexStart + IndexesPerBLAS, Mesh->Mesh.IndexCount);
DynamicBLAS[instance] = CreateBLAS(true, indexStart, indexEnd - indexStart);
}
CreateTLASInstanceBuffer();
UploadTLASInstanceBuffer();
// Wait for bottom level builds to finish before using it as input to a toplevel accel structure. Also wait for the instance buffer upload to complete.
@ -91,7 +106,7 @@ void VkLevelMesh::CreateVulkanObjects()
.AddMemory(VK_ACCESS_ACCELERATION_STRUCTURE_WRITE_BIT_KHR | VK_ACCESS_TRANSFER_WRITE_BIT, VK_ACCESS_ACCELERATION_STRUCTURE_READ_BIT_KHR | VK_ACCESS_SHADER_READ_BIT)
.Execute(fb->GetCommands()->GetTransferCommands(), VK_PIPELINE_STAGE_ACCELERATION_STRUCTURE_BUILD_BIT_KHR | VK_PIPELINE_STAGE_TRANSFER_BIT, VK_PIPELINE_STAGE_ACCELERATION_STRUCTURE_BUILD_BIT_KHR);
CreateTopLevelAS(DynamicBLAS.AccelStruct ? 2 : 1);
CreateTopLevelAS(InstanceCount);
// Finish building the accel struct before using it from the shaders
PipelineBarrier()
@ -109,7 +124,18 @@ void VkLevelMesh::CreateVulkanObjects()
void VkLevelMesh::BeginFrame()
{
bool accelStructNeedsUpdate = Mesh->UploadRanges.Index.Size() != 0 || Mesh->UploadRanges.Vertex.Size() != 0;
InstanceCount = (Mesh->Mesh.IndexCount + IndexesPerBLAS - 1) / IndexesPerBLAS;
bool accelStructNeedsUpdate = Mesh->UploadRanges.Index.Size() != 0;
for (const MeshBufferRange& range : Mesh->UploadRanges.Index)
{
int start = range.Start / IndexesPerBLAS;
int end = (range.End + IndexesPerBLAS - 1) / IndexesPerBLAS;
for (int i = start; i < end; i++)
{
DynamicBLAS[i].NeedsUpdate = true;
}
}
UploadMeshes();
@ -124,12 +150,22 @@ void VkLevelMesh::BeginFrame()
{
// To do: we should reuse the buffers.
// Create a new BLAS for each segment that changed
auto deletelist = fb->GetCommands()->DrawDeleteList.get();
deletelist->Add(std::move(DynamicBLAS.ScratchBuffer));
deletelist->Add(std::move(DynamicBLAS.AccelStructBuffer));
deletelist->Add(std::move(DynamicBLAS.AccelStruct));
for (int instance = 0; instance < InstanceCount; instance++)
{
BLAS& blas = DynamicBLAS[instance];
if (blas.NeedsUpdate)
{
deletelist->Add(std::move(blas.ScratchBuffer));
deletelist->Add(std::move(blas.AccelStructBuffer));
deletelist->Add(std::move(blas.AccelStruct));
DynamicBLAS = CreateBLAS(true, 0, Mesh->Mesh.IndexCount);
int indexStart = instance * IndexesPerBLAS;
int indexEnd = std::min(indexStart + IndexesPerBLAS, Mesh->Mesh.IndexCount);
blas = CreateBLAS(true, indexStart, indexEnd - indexStart);
}
}
deletelist->Add(std::move(TopLevelAS.TransferBuffer));
deletelist->Add(std::move(TopLevelAS.InstanceBuffer));
@ -142,7 +178,7 @@ void VkLevelMesh::BeginFrame()
.AddMemory(VK_ACCESS_ACCELERATION_STRUCTURE_WRITE_BIT_KHR | VK_ACCESS_TRANSFER_WRITE_BIT, VK_ACCESS_ACCELERATION_STRUCTURE_READ_BIT_KHR | VK_ACCESS_SHADER_READ_BIT)
.Execute(fb->GetCommands()->GetTransferCommands(), VK_PIPELINE_STAGE_ACCELERATION_STRUCTURE_BUILD_BIT_KHR | VK_PIPELINE_STAGE_TRANSFER_BIT, VK_PIPELINE_STAGE_ACCELERATION_STRUCTURE_BUILD_BIT_KHR);
UpdateTopLevelAS(DynamicBLAS.AccelStruct ? 2 : 1);
UpdateTopLevelAS(InstanceCount);
// Finish building the accel struct before using it from the shaders
PipelineBarrier()
@ -295,6 +331,8 @@ VkLevelMesh::BLAS VkLevelMesh::CreateBLAS(bool preferFastBuild, int indexOffset,
.DebugName("BLAS.ScratchBuffer")
.Create(fb->GetDevice());
blas.DeviceAddress = blas.AccelStruct->GetDeviceAddress();
buildInfo.dstAccelerationStructure = blas.AccelStruct->accelstruct;
buildInfo.scratchData.deviceAddress = blas.ScratchBuffer->GetDeviceAddress();
@ -311,13 +349,13 @@ void VkLevelMesh::CreateTLASInstanceBuffer()
{
TopLevelAS.TransferBuffer = BufferBuilder()
.Usage(VK_BUFFER_USAGE_TRANSFER_SRC_BIT, VMA_MEMORY_USAGE_CPU_ONLY)
.Size(sizeof(VkAccelerationStructureInstanceKHR) * 2)
.Size(sizeof(VkAccelerationStructureInstanceKHR) * DynamicBLAS.size())
.DebugName("TopLevelAS.TransferBuffer")
.Create(fb->GetDevice());
TopLevelAS.InstanceBuffer = BufferBuilder()
.Usage(VK_BUFFER_USAGE_SHADER_DEVICE_ADDRESS_BIT | VK_BUFFER_USAGE_ACCELERATION_STRUCTURE_BUILD_INPUT_READ_ONLY_BIT_KHR | VK_BUFFER_USAGE_TRANSFER_DST_BIT)
.Size(sizeof(VkAccelerationStructureInstanceKHR) * 2)
.Size(sizeof(VkAccelerationStructureInstanceKHR) * DynamicBLAS.size())
.DebugName("TopLevelAS.InstanceBuffer")
.Create(fb->GetDevice());
}
@ -338,7 +376,7 @@ void VkLevelMesh::CreateTopLevelAS(int instanceCount)
accelStructTLDesc.geometry.instances = { VK_STRUCTURE_TYPE_ACCELERATION_STRUCTURE_GEOMETRY_INSTANCES_DATA_KHR };
accelStructTLDesc.geometry.instances.data.deviceAddress = TopLevelAS.InstanceBuffer->GetDeviceAddress();
uint32_t maxInstanceCount = 2;
uint32_t maxInstanceCount = (uint32_t)DynamicBLAS.size();
VkAccelerationStructureBuildSizesInfoKHR sizeInfo = { VK_STRUCTURE_TYPE_ACCELERATION_STRUCTURE_BUILD_SIZES_INFO_KHR };
vkGetAccelerationStructureBuildSizesKHR(fb->GetDevice()->device, VK_ACCELERATION_STRUCTURE_BUILD_TYPE_DEVICE_KHR, &buildInfo, &maxInstanceCount, &sizeInfo);
@ -400,25 +438,21 @@ void VkLevelMesh::UpdateTopLevelAS(int instanceCount)
void VkLevelMesh::UploadTLASInstanceBuffer()
{
VkAccelerationStructureInstanceKHR instances[2] = {};
instances[0].transform.matrix[0][0] = 1.0f;
instances[0].transform.matrix[1][1] = 1.0f;
instances[0].transform.matrix[2][2] = 1.0f;
instances[0].mask = 0xff;
instances[0].flags = 0;
instances[0].accelerationStructureReference = DynamicBLAS.AccelStruct->GetDeviceAddress();
VkAccelerationStructureInstanceKHR instance = {};
instance.transform.matrix[0][0] = 1.0f;
instance.transform.matrix[1][1] = 1.0f;
instance.transform.matrix[2][2] = 1.0f;
instance.mask = 0xff;
instance.flags = 0;
/*
instances[1].transform.matrix[0][0] = 1.0f;
instances[1].transform.matrix[1][1] = 1.0f;
instances[1].transform.matrix[2][2] = 1.0f;
instances[1].mask = 0xff;
instances[1].flags = 0;
instances[1].accelerationStructureReference = DynamicBLAS.AccelStruct->GetDeviceAddress();
*/
auto data = (uint8_t*)TopLevelAS.TransferBuffer->Map(0, sizeof(VkAccelerationStructureInstanceKHR) * DynamicBLAS.size());
for (BLAS& blas : DynamicBLAS)
{
instance.accelerationStructureReference = blas.DeviceAddress;
auto data = (uint8_t*)TopLevelAS.TransferBuffer->Map(0, sizeof(VkAccelerationStructureInstanceKHR) * 2);
memcpy(data, instances, sizeof(VkAccelerationStructureInstanceKHR) * 2);
memcpy(data, &instance, sizeof(VkAccelerationStructureInstanceKHR));
data += sizeof(VkAccelerationStructureInstanceKHR);
}
TopLevelAS.TransferBuffer->Unmap();
fb->GetCommands()->GetTransferCommands()->copyBuffer(TopLevelAS.TransferBuffer.get(), TopLevelAS.InstanceBuffer.get());

6
src/common/rendering/vulkan/vk_levelmesh.h
View file

@ -93,6 +93,8 @@ private:
std::unique_ptr<VulkanBuffer> ScratchBuffer;
std::unique_ptr<VulkanBuffer> AccelStructBuffer;
std::unique_ptr<VulkanAccelerationStructure> AccelStruct;
VkDeviceAddress DeviceAddress = 0;
bool NeedsUpdate = false;
};
void Reset();
@ -127,7 +129,9 @@ private:
std::unique_ptr<VulkanBuffer> NodeBuffer;
BLAS DynamicBLAS;
std::vector<BLAS> DynamicBLAS;
int IndexesPerBLAS = 0;
int InstanceCount = 0;
struct
{