Backends: DirectX12: reuse a command list and allocator for texture uploads. (#8963, #8465)

This commit is contained in:
Rémy Tassoux
2025-09-27 00:45:10 +02:00
committed by ocornut
parent 1c87024840
commit 217bc445ff
2 changed files with 20 additions and 13 deletions

View File

@@ -20,6 +20,7 @@
// CHANGELOG
// (minor and older changes stripped away, please see git history for details)
// 2025-09-27: DirectX12: Reuse a command list and allocator for texture uploads instead of recreating them each time.
// 2025-09-18: Call platform_io.ClearRendererHandlers() on shutdown.
// 2025-06-19: Fixed build on MinGW. (#8702, #4594)
// 2025-06-11: DirectX12: Added support for ImGuiBackendFlags_RendererHasTextures, for dynamic font atlas.
@@ -97,6 +98,9 @@ struct ImGui_ImplDX12_Data
ID3D12DescriptorHeap* pd3dSrvDescHeap;
UINT numFramesInFlight;
ID3D12CommandAllocator* pTexCmdAllocator;
ID3D12GraphicsCommandList* pTexCmdList;
ImGui_ImplDX12_RenderBuffers* pFrameResources;
UINT frameIndex;
@@ -448,13 +452,12 @@ void ImGui_ImplDX12_UpdateTexture(ImTextureData* tex)
props.CPUPageProperty = D3D12_CPU_PAGE_PROPERTY_UNKNOWN;
props.MemoryPoolPreference = D3D12_MEMORY_POOL_UNKNOWN;
// FIXME-OPT: Can upload buffer be reused?
// FIXME-OPT: Could upload buffer be kept around, reused, and grown only when needed? Would that be worth it?
ID3D12Resource* uploadBuffer = nullptr;
HRESULT hr = bd->pd3dDevice->CreateCommittedResource(&props, D3D12_HEAP_FLAG_NONE, &desc,
D3D12_RESOURCE_STATE_GENERIC_READ, nullptr, IID_PPV_ARGS(&uploadBuffer));
IM_ASSERT(SUCCEEDED(hr));
// Create temporary command list and execute immediately
ID3D12Fence* fence = nullptr;
hr = bd->pd3dDevice->CreateFence(0, D3D12_FENCE_FLAG_NONE, IID_PPV_ARGS(&fence));
IM_ASSERT(SUCCEEDED(hr));
@@ -462,15 +465,9 @@ void ImGui_ImplDX12_UpdateTexture(ImTextureData* tex)
HANDLE event = ::CreateEvent(0, 0, 0, 0);
IM_ASSERT(event != nullptr);
// FIXME-OPT: Create once and reuse?
ID3D12CommandAllocator* cmdAlloc = nullptr;
hr = bd->pd3dDevice->CreateCommandAllocator(D3D12_COMMAND_LIST_TYPE_DIRECT, IID_PPV_ARGS(&cmdAlloc));
IM_ASSERT(SUCCEEDED(hr));
// FIXME-OPT: Can be use the one from user? (pass ID3D12GraphicsCommandList* to ImGui_ImplDX12_UpdateTextures)
ID3D12GraphicsCommandList* cmdList = nullptr;
hr = bd->pd3dDevice->CreateCommandList(0, D3D12_COMMAND_LIST_TYPE_DIRECT, cmdAlloc, nullptr, IID_PPV_ARGS(&cmdList));
IM_ASSERT(SUCCEEDED(hr));
bd->pTexCmdAllocator->Reset();
bd->pTexCmdList->Reset(bd->pTexCmdAllocator, nullptr);
ID3D12GraphicsCommandList* cmdList = bd->pTexCmdList;
// Copy to upload buffer
void* mapped = nullptr;
@@ -535,8 +532,6 @@ void ImGui_ImplDX12_UpdateTexture(ImTextureData* tex)
fence->SetEventOnCompletion(1, event);
::WaitForSingleObject(event, INFINITE);
cmdList->Release();
cmdAlloc->Release();
::CloseHandle(event);
fence->Release();
uploadBuffer->Release();
@@ -776,6 +771,14 @@ bool ImGui_ImplDX12_CreateDeviceObjects()
if (result_pipeline_state != S_OK)
return false;
// Create command allocator and command list for ImGui_ImplDX12_UpdateTexture()
HRESULT hr = bd->pd3dDevice->CreateCommandAllocator(D3D12_COMMAND_LIST_TYPE_DIRECT, IID_PPV_ARGS(&bd->pTexCmdAllocator));
IM_ASSERT(SUCCEEDED(hr));
hr = bd->pd3dDevice->CreateCommandList(0, D3D12_COMMAND_LIST_TYPE_DIRECT, bd->pTexCmdAllocator, nullptr, IID_PPV_ARGS(&bd->pTexCmdList));
IM_ASSERT(SUCCEEDED(hr));
hr = bd->pTexCmdList->Close();
IM_ASSERT(SUCCEEDED(hr));
return true;
}
@@ -790,6 +793,8 @@ void ImGui_ImplDX12_InvalidateDeviceObjects()
bd->commandQueueOwned = false;
SafeRelease(bd->pRootSignature);
SafeRelease(bd->pPipelineState);
SafeRelease(bd->pTexCmdList);
SafeRelease(bd->pTexCmdAllocator);
// Destroy all textures
for (ImTextureData* tex : ImGui::GetPlatformIO().Textures)