I am trying to scale and repeat a Cubemap with Latitude-Longitude mapping layout just as you would do with classical UV mapping but without any interesting result. This should be used as a skybox.
This comes from the fact that the coordinates are in 3D space and we can't apply this simple formula texcoord.xy * scale.xy + offset.xy
How would you handle such features : scaling which involves tiling and offsetting.
samplerCUBE _TexCube; texCUBE(_TexCube, float3); This doesn't really answer the question but is a workaround. Beware it's hack time :)
Instead of using the texCUBE and samplerCube I'll be using the tex2D method and a simple sampler to sample the texture.
As I am using a sphere mesh, I generate 2D UVs like this.
float x = atan2(vertex.x, vertex.z) / PI; x = x / 2.0 + 0.5; // To remap from 0 to 1 float y = vertex.y / 2.0 + 0.5; // Also remap from 0 to 1 float3 color = tex2D(sampler, float2(x, y) * scale.xy + offset.xy); It's a bit hacky but using this I have 2D texture coordinates for my texture.