renderman’s micro-tesselation

since i’m allowed to use pixar’s renderman for my upcoming short to be released by the end of this summer here at vfs, learning this legendary rendering system is a must since i don’t expect that i’ll have much time left at the end of the production in june. so i’ll post some research & development notes about my experiences with renderman here rather regularly.

in this blog post, i’ll start with one of the first things i encountered in renderman that are special: the micro-tesselation available for polygonal objects (down to 1 pixel!). as i’m used the crank up the tesselation of polygons and smoothen out the normals i’m surprised to see that this work is not necessary with renderman; well, at least not to the density of the tesselation i’m used to go. sounds weird? here’s what i mean:

take any polygonal object and go to its attributes and be sure you have your shape node (tab) activated. go to attributes > renderman > subdiv scheme, now a new attribute called extra renderman attributes should appear in your attributes window. by default it’s set to catmull-clark which works fine for quads: if you have tris, try loop as subdivision scheme.

this is what i get if i render my upcoming character’s shoe (lt. lou) with renderman, micro-tesselated with subdiv scheme catmull-clark. you can also set the scheme to none again, if you want to have the ‘usual behaviour’ (like when you use maya software as renderer).

so this basically means i can save the step of tesselating my object too far and can do my high-quality animation render this way. this also speeds up my animation work a lot when i’m digging into my graph editor and my now very perfomant viewport doesn’t have to update too many vertices.