Bumpmaps that actually change the object are called displacement maps. Instead of bumpmapping it's called displacement mapping. Bryce doesn't have a feature build in for displacement mapping on anything but terrains and lattices. Many other programs do support it, but bryce doesn't. I did however once see a link way back when Bryce 5 was still under construction that claimed that B5 was going to have Displacement mapping along with a couple of other things as well like motion-blurr. I never bookmarked the site unfortunately and I can't find it anymore. If the site told the truth there may still be some coding for it hidden in Bryce, but it's probably not usable.

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