Render to Texture2DArray slices in DirectX11?

Question

I would like to set a slice of a Texture2DArray as a render target in D3D/DirectX11. It's not clear how to do this.

What I'm looking for is the DirectX equivalent of glFramebufferTextureLayer(), which sets a slice of a GL_TEXTURE_2D_ARRAY_EXT as a texture resource of a Framebuffer Object.

In D3D11, you set a render target using ID3D11DeviceContext::OMSetRenderTargets, and you can set a Texture2DArray resource view as a render target. However, the only way I see to select which slice of the texture is painted is to use the SV_RenderTargetArrayIndex semantic in an HLSL geometry shader. (The semantic is only available in a geometry shader).

My pipeline doesn't have a geometry shader, and I don't know at compile time which primitive type I will be rendering - I'm reading models out of input files. It seems like, to add a passthrough geometry shader I would need one shader program for every possible primitive type (terrible).

The desired output slice will not change between rendering passes. Is there no way to set a slice of a Texture2DArray as a render target without using a geometry shader?

Answer 1

You can create separate render target views for every slice and then set it using ID3D11DeviceContext::OMSetRenderTargets.

D3D11_RENDER_TARGET_VIEW_DESC desc;
desc.ViewDimension = D3D11_RTV_DIMENSION_TEXTURE2D;
desc.Texture2D.MipSlice = D3D11CalcSubresource(0, arraySlice, mipLevels);

Information about subresources.