I've got a nasty little conundrum that I'm hoping folks may be able to help with. For the purposes of example, assume I am texturing a terrain, and need to atlas a number of textures together to avoid reaching the sampler limit - array textures and volume textures are not available resources.
We can atlas simply, but we will get nasty seams where textures border thanks to sampling. If we create artificial borders between atlased textures, we'll get artifacts at high incidence viewing angles.
We've looked at alternative sampling techniques, but haven't found a viable solution. Our Dx9 solution uses tex2dgrad, but we're primarily working in Dx11 where tex2dgrad doesn't seem to be available. Due to a limitation with our shader system, we are unable to pass or declare a sampler state, so we cannot use the updated equivalent samplegrad either.
Anyone have any ideas?