thanks – will have a look – this sounds just like what I need!
From: Alan Fregtman Sent: Thursday, May 10, 2012 3:25 PM To: softimage@listproc.autodesk.com Subject: Re: pointvelocity to drive motion vectors on geometry - does it work? Yeah; for a UserMotion example, go to your XSI_SAMPLES project under: /Scenes/ICE/RotatingGearWithICEUserMotions.scn On Thu, May 10, 2012 at 3:43 AM, Ciaran Moloney <moloney.cia...@gmail.com> wrote: Hi, PointVelocity applies to particles only. If you're using MR, then there's an ICE attribute usermotion that you can use to define custom vectors for motion blur. On Thu, May 10, 2012 at 8:32 AM, <pete...@skynet.be> wrote: Hi, I’m using the mip_motion_vectors output shader. My non-simulated particle cloud (sticking to a surface) shows up black which makes sense I guess. No worries, I’m looking up the PointVelocity at the surface and saving this on the particles – and magically the motion vectors are fixed and blend perfectly with the surface. Now I have some geometry with incorrect motion vectors (I think) – and I was hoping to accomplish the same thing: calculating motion vectors (difference between previous and current frames’ pointposition ?) and saving it as a PointVelocity attribute. However – it doesnt seem to be working – no matter what I try, the PointVelocity attribute doesnt seem to affect motion vectors – as it did for the particles. Has anyone done this? Does it / should it work? thanks for any pointers.