Question: if I bilinearily downsample the depth image and create worldspace normals from the downsampled perpixel depth values, do I get the same normals if I would have create the perpixel normals from the hires depth values which I would then have downsampled, too???
If you would re-normalize the downsampled normals they should be the same you would get when creating them from downsampled depth values. But I´m not 100% sure. It´s worth a try at least. But consider, in a post-processing step you´ll get wrong normals along 'sharp' edges if you dont handle that case separatly.
