Have a look at https://github.com/NightCreature/SpaceSim/blob/master/SpaceSim/Graphics/RenderSystem.cpp and function initialiseCubemapRendererAndResources.

This initialises a cubemaps and SRVs and RTVs for use in a cubemap renderer, were the target and resource are cubemaps but are rendered to as single target RTs. This is D3D11 but I have a feeling this will extend into D3D12 too.

An additional D3D11 example using cube map arrays for which an RTV is created for each face:

https://github.com/matt77hias/MAGE/blob/master/MAGE/MAGE/src/rendering/buffer/shadow_map_buffer.cpp

I just wanted to confirm that it's basically the same in D3D12 as it is in D3D11: you just need to specify which array slice the SRV will read from by filling out the "Texture2DArray.FirstArraySlice" and Texture2DArray.ArraySize" members of the D3D12_SHADER_RESOURCE_VIEW_DESC structure. You can also do this to make a view into a sub-array if you want, or to make a view that only sees a subset of the mip levels.

5 minutes ago, mark_braga said:

Thanks for posting these links. They have given a lot of insight.

So just to confirm if I want to create a 2D view of face 3 of a cubemap, will the code look something like this?

SRV_DESC desc = {};
desc.dimension = TEXTURE_2D_ARRAY;
desc.tex2DArray.firstArraySlice = 3; // Face 3 in the cubemap
desc.tex2DArray.arraySize = 1;       // Only need one face
addSRV(pCubeMapResource, &desc);

Thank you

Use index 2 because in computer science we start counting at 0. Also rememeber that the faces are in the cubemap as you render into them so if you have face 0 be positive Z axis that is the image you will get back

My local transforms look in the direction of the positive  z-axis. The y-axis points up and the x-axis points to the left. This results in the following transformation matrices and indices for each of the six planes of the cube map.

static const XMMATRIX rotations[6] = {
    XMMatrixRotationY(-XM_PIDIV2), // Look: +x Index: 0
    XMMatrixRotationY( XM_PIDIV2), // Look: -x Index: 1
    XMMatrixRotationX( XM_PIDIV2), // Look: +y Index: 2
    XMMatrixRotationX(-XM_PIDIV2), // Look: -y Index: 3
    XMMatrixIdentity(),            // Look: +z Index: 4
    XMMatrixRotationY(XM_PI),      // Look: -z Index: 5
 };