| Is this an Octane-specific problem or do you also get it in other renderers? Marsel Khadiyev (Software Developer, EPHERE Inc.) |
| I just talked to them and it seems like they cannot create motion blur for the mesh that changes vertice count everyframe. So it is them. I hope they will find solution one day. |
| Yes, that is a problem. Mesh needs to be sampled at sub-frame interval, in that case topology changes is not a problem. Marsel Khadiyev (Software Developer, EPHERE Inc.) |
| Some approach usually taken by renderer developpers is motion vectors. Even at sub-frame it's not possible to get consistent motion blur or topology-changing objects. The only practical solution is to assign a motion vector per vertex. That's what Arnold does, for example and I'm sure many others do. There are two ways though: defining and using a standard format for motion vectors that everybody could use (I'm not certain but I think openVDB does provide motion vectors capability) or the render engine generate its own. The advantage of motion vectors compared to sub-frame sampling is that motion blur can, if needed, be stronger than the actual motion between a 2 frames interval (to mimick a longer exposure time). |
| Yes, this can be arranged. However the issue is then how is this data passed on to the renderer and if we'd have to write translators for each renderer which do that. Marsel Khadiyev (Software Developer, EPHERE Inc.) |
| The best approach is probably to either do nothing and let renderer developers do their own motion vector baker for topology-changing meshes, or adopting a standard (if any) that might be available in openVDB. I'm all for standards but well... |
| we talked to octane and they tell us it is impossible to do because everyframe mesh changes topology and vertex count I hope one day they can figure it out, |
