Hello,
In OpenGL, you must enable the seamless cubemap filtering with glEnable(GL_TEXTURE_CUBE_MAP_SEAMLESS).
I never saw something similar on Direct3D but I read starting Direct3D 10 the cubemap is always seamless filtered.
So we had to use a trick to have seamless filtering to have proper lookup before Direct3D 10.
Is it ensured nowadays on absolutely all modern API (D3D12, Vulkan, Metal…) to be seamless filtering only?
Thanks!