Once you are an expert in DirectX 11, then it still may not make sense to use DirectX 12 for your particular project unless you are finding that the CPU overhead of the DirectX 11 API really is a bottleneck. Even if it makes sense for you to eventually use DirectX 12, the API design and documentation assumes you are already an expert in DirectX 11 programming and HLSL. If you are new to graphics programming with DirectX, then I strongly recommend you use DirectX 11. Graphics programming and debugging is already a challenge, and using DirectX 12 complicates it immensely with timing problems (akin to the kinds of risks you can have doing multi-threaded lockfree programming), more vendor-specific behavior which requires more test validation, resource management problems that can happen over multiple frames, and more responsibility for how all your programmable shaders manage information sharing with the PCU. This is very powerful for allowing applications much more control over how the hardware is driven, but it means that the onus is on the programmer to get everything right even under unusual scenarios and across a wide range of hardware. With DirectX 12, the DirectX Runtime does very little and the application is responsible for everything the DirectX 11 Runtime would handle for you. With DirectX 11, the API is 'low-level' but the DirectX Runtime manages the video memory, coordinates resource upload/download, handles buffer renaming, and ensures proper synchronization between the GPU and the CPU. The difference is in how the CPU and memory are managed. They both drive the same hardware and have access to the same hardware features. DirectX 11 and DirectX 12 solve the same problem but in different ways.

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