Unity with DX11 texture can't be registered in CUDA

[davidAlgis]

When I try to register in CUDA a texture DX11 that has been created in Unity, I get the following error : ErrorCuda error: 1 invalid argument.

[davidAlgis]

The texture that has been created in Unity with DX11 API, will have the type DXGI_FORMAT_R32G32B32A32_TYPELESS in native plugin. Therefore, they can't be used like that to be registered in CUDA with cudaGraphicsD3D11RegisterResource, because it doesn't accept this format.

[davidAlgis]

I use this code to see that :

    ID3D11Texture2D *d3dtex = (ID3D11Texture2D *)_textureHandle;
    assert(d3dtex);
    D3D11_TEXTURE2D_DESC texDesc;
    d3dtex->GetDesc(&texDesc);

    DXGI_FORMAT format = texDesc.Format;
    Log::log().debugLog(std::to_string(format));

[davidAlgis]

This issue was already reported here : see issue tracker

[davidAlgis]

To solve this issue I have to create another texture and copy the content of the texture created in Unity into it. This will cause an overhead...

[deibich]

Hello @davidAlgis,

we also plan to use Unity with Cuda and got some code working. During my research I stumbled over your project which looks very promising.

Because we focus on windows + directx I started to implement d3d11.
https://github.com/deibich/InteropUnityCUDA/commits/d3d11

As you can see I used Texture2D and Texture2DArray instead of RenderTexture to get rid of the problem with format ..._TYPLESS.

To solve this issue I have to create another texture and copy the content of the texture created in Unity into it. This will cause an overhead...

Does the "action_sample_texture_array" work with this workaround?

[davidAlgis]

Hi @deibich,
Nice to see that my work is being useful to someone.
Thanks for the tips to change RenderTexture to Texture2D, after I saw the issue tracker, I had completely given up to make it work without a copy.
This morning I push a first version that work for texture 2D with this copy, but as I except it cause a big overhead. Thanks to you, I push another version that work for texture 2D without a copy and the performances are better ! Now I will tackle the problem of the texture 2D array.

To solve this issue I have to create another texture and copy the content of the texture created in Unity into it. This will cause an overhead...

Does the "action_sample_texture_array" work with this workaround?

On OpenGL, I could registered directly the texture array into a cuda surface object, that was then written with surf3DWrite. Therefore, no copy was needed. I hope to find a similar solution for dx11. Do not hesitate if you have any questions.

[davidAlgis]

One drawback of using Texture2D instead of RenderTexture is that a Texture2D cannot be written in a compute shader. You get the following error if you try :

Attempting to bind texture as UAV but the texture wasn't created with the UAV usage flag set!

I think I will let the 2 options (with and without copy), just in case.