Instancing and geometry primitives
Posted: Wed Aug 24, 2011 4:08 am
I've been doing a lot of strand (hair) scenes recently and it got me thinking. Mantal Ray has this thing called primitives, which are simple geometry created at rendertime. So to do hair, grass, etc it just requires a choice of basic shape the renderer knows from a list and it gets duplicated or extruded along a line to create geometry on the fly. I am kinda hoping that some day this could be implemented in Octane as a part of the instancing system.
Benefits would be huge. Right now rendering a scene with hundreds of thousands of hairs would require exporting them to Octane as geometry (multi-million-polygon meshes), which would take forever for animation. If Octane "knew" a couple of basic shapes and what to do with them (extrude along a curve, which, from what i understand, is already happening in the exporter for Softimage, as explained by face in this thread: http://www.refractivesoftware.com/forum ... 557#p61557), literally no geometry would have to be exported for hair. Only strand positions would be needed. The resulting geometry would still have to be voxelized, but the pain of waiting for exports would be gone.
I guess whether it's possible and really beneficial would be a good question to ask Andrey Kozlov. Or should i say Karba ;]
Benefits would be huge. Right now rendering a scene with hundreds of thousands of hairs would require exporting them to Octane as geometry (multi-million-polygon meshes), which would take forever for animation. If Octane "knew" a couple of basic shapes and what to do with them (extrude along a curve, which, from what i understand, is already happening in the exporter for Softimage, as explained by face in this thread: http://www.refractivesoftware.com/forum ... 557#p61557), literally no geometry would have to be exported for hair. Only strand positions would be needed. The resulting geometry would still have to be voxelized, but the pain of waiting for exports would be gone.
I guess whether it's possible and really beneficial would be a good question to ask Andrey Kozlov. Or should i say Karba ;]