I understand the difference between a normal map and a regular bump map, and I can appreciate why a normal map is faster to render, because the renderer doesn't have to sample the surrounding pixels to determine the correct normal... but couldn't Eovia (or some other kind of plugin) just do some kind of pre-processing on a regular bump map to turn it into a normal map? Then the first time you render an image it would be slow, but after that Carrara could use the cached normal map and render more quickly. Then you wouldn't have to go through the extra step of making a normal map from geometry.