Guide [Crash] DX12 Hook — Window Resizing and Resolution Change Crashes

[byte_corvus]

Dealing with DX12 hooks is always a headache when it comes to the swapchain. You've got your overlay drawing perfectly, and then you touch the window border or swap resolution — instant crash. This is a classic hurdle when hijacking the Present or ExecuteCommandLists flow in D3D12.

The Technical Breakdown
The error code mentioned (likely a variation of DXGI_ERROR_INVALID_CALL) during a resize usually means your hook is holding onto references that the swapchain needs to release. In DX12, when the window resizes or the resolution changes, the engine triggers ResizeBuffers. For this to succeed, the following must happen:

1. You must release all pointers to the back buffers (ID3D12Resource).
2. The command queue must be flushed to ensure the GPU is finished with those resources.
3. The descriptors in your RTV heap must be invalidated or updated.

If your HookDx12 implementation is still holding a reference or has an active descriptor pointing to the old buffers, the swapchain resize will fail, and the device will often hit a removed state or throw an invalid call error.

Troubleshooting & Fixes

1. Check if you have hooked IDXGISwapChain::ResizeBuffers. If you haven't, that is your primary issue. You need to intercept this call to clean up your local resources before the game tries to resize.
2. In your ResizeBuffers proxy, call Release() on your render target resources and set them to nullptr.
3. After calling the original ResizeBuffers function, you must re-acquire the back buffers and recreate your Render Target Views (RTVs).
4. Ensure your command allocator and list are reset properly after the resize.

Spoiler: Common DX12 Hook Mistakes

Often people forget that D3D12 is much more manual than D3D11. You can't just ignore the resize event. If you are using a library like ImGui, make sure you call ImGui_ImplDX12_InvalidateDeviceObjects() and then recreate them after the resize is finished. Also, verify that your fence synchronization is solid; if the GPU is still processing a frame while you try to resize the buffers, it will result in a crash.

Anyone else dealt with this specific 0x4000 error when handling adaptation resolution?