DX11 or DX12 당신의 선택은?

 

	D3D11	D3D12
Resources	ID3D11Resource ID3D11Buffer ID3D11Device::CreateBuffer ID3D11Texture1D ID3D11Device::CreateTexture1D ID3D11Texture2D ID3D11Device::CreateTexture2D ID3D11Texture3D ID3D11Device::CreateTexture3D	ID3D12Resource ID3D12Device::CreateCommittedResource (Committed : Virtual address space with physical pages for the resource)
Resources(tiled)	D3D11_RESOURCE_MISC_TILED D3D11_RESOURCE_MISC_TILED_POOL	ID3D12Device::CreateReservedResources (Reserved : Virtual memory only) ID3D12Device::CreateHeap (page-mappable physical memory)
Resources(data upload)	Appearance of single timeline number of copies not obvious initial data(D3D11_SUBRESOURCE_DATA) UpdataSubresource Map	GET Timeline(1 copy) : CopyTextureRegion, CopyBufferRegion from mappable memory CPU Timeline(1 copy) : Map Shared Timeline(2 copies) : D3DX12 UpdateSubresource helper
Shaders and State Objects	ID3D11Device::Create* ID3D11DeviceContext::*Set* * : VS/PS/HS/DS/GS/CS/OM/RS/SO/IA or : Shader, Input Layout, Blend State, Rasterizer State, Depth Stencil State	ID3D12Device::Create*PipelineState ID3D12GraphicsCommandList::SetPipelineState
Work Submission	Automatic(Driver-managed) ID3D11DeviceContext::Flush(Optional)	ID3D12CommandList (Similar to D3D11 defered context, Records commands to be submitted later) ID3D12CommandAllocator (Backing memory for commands) ID3D12CommandQueue (FIFO set of work to schedule, Single queue in D3D11)
CPU/GPU Synchronization	Automatic(Diver-managed) CPU waits for GPU during Present()/Map()	ID3D12Fence (GPU can signal when it is done with a chunk of work) Memory must not be destroyed until GPU has completed (Committed resources, heaps, command allocators, etc) Memory must not be over-written until GPU has completed (CPU-accesible resources with GPU operations reading from them need to be "renamed" to avoid stalling GPU)
CPU/GPU Synchronization	Map(D3D11_MAP_WRITE_DISCARD)	Allocate additional memory Use fences to understand when GPU operations are done Consider ring buffers consisting of large buffers
Resouce Binding	Views ID3D11Device::Create*View ID3D11*View ID3D11DeviceContext::*Set*	Descriptors ID3D12Device::Create*View ID3D12Device::CreateDescriptorHeap ID3D12DescriptorHeap ID3D12CommandList::Set*RootDescriptorTable
Resource Binding(Root Signature)	Implicit Each shader stage has descriptor tables mapping 128 Shader-Resource-Views to t0~t127, 14 Constant-Buffers to b0~b13 etc. Incremental bindings, driver does renaming of descriptor tables Root Parameter - Descriptor Table 0 => {VS descriptor Range b0~b13} 1 => {VS descriptor Range t0~t127} 2 => {VS descriptor Range s0~s16} 3 => {VS descriptor Range b0~b13} ........................................................ 14 => {VS descriptor Range s0~s16} 15 => {VS descriptor Range u0~u63}	Explicit App controls mapping from root parameter all the way to shader register App responsible for renaming descriptor tables App can control descriptors are shared between shader stages frequency of updates, etc
Resource State	Automatic(dirver-tracked)	App responsible for telling driver when resource usage is changing (Fine-grained synchronization(pipeline stalls) e.g RTV => SRV Cache flushes Memory layout changes(RTV/DSV/decompression)) D3D12 resource transition barrier
Other Barriers	ID3D11DeviceContext2::TiledResourceBarrier Dispatch/Draw implied UAV barrier	D3D12 aliasing barrier By default, UAV ops in subsequent draw/dispatches can happen in parallel (Explicit UAV barrier to serialize Perf gains to be had if workloads can be parallelized)
Swapchains	DXGI_SWAP_EFFECT (SEQUENTIAL, DISCARD, FLIP_SEQUENTIAL) Automatic buffer rotation (Only need RTV for back buffer 0)	DXGI_SWAP_EFFECT (FLIP_SEQUENTIAL, FLIP_DISCARD) Explicit buffer rotation (Need RTV for each back buffer IDXGISwapChain3::GetCurrentBackBufferIndex to choose which one to render to)
Fixed-Function Rendering	GenerateMips, DrawAuto	App is responsible for creating shaders to do these operations D3DX12 may include a library of examples
Misc	ID3D11Query / ID3D11Predicate (GetData) UAV/SO hidden counter Resource dynamic MinLOD Draw*Indirect/DispatchIndirect DepthStencil formats interleaved ResizeTilePool	ID3D12QueryHeap / ID3D12Resource (ResolveQueryData) App responsible for allocation and management of SO/UAV counters SRV descriptor static Min LOD ExecuteIndirect DepthStencil formats planar Reserved resource mapped to multiple heaps