View Full Version : Dynamics: Strip Position and Rotation Data and Apply to Null

10-30-2009, 10:30 AM
I've got a bunch of tumbling cubes that were animated using hard fx and a collision object. We need to capture the position and rotation data from these cubes and apply that data to a null. All of the dynamics baking I've looked at seems to save point data from the entire mesh.

What is the best method for doing this?

10-30-2009, 04:34 PM
On Null item you need to use Motion Modifier > Motion Baker, that's in Motion Options window. Null should be made child of original item. After baking processes (play preview), unparent item from source.

10-30-2009, 04:56 PM
Thanks for the response Sensei. I think I am missing a key step though...

1. Apply HardFX to my cube.
2. Hit Calculate.
3. Cube now tumbles and bounces.
4. How do I make the motion on the cube become keyframe data? If I parent the null to the cube at this point the null does not follow the cube's calculated motion.

Any insight on step 4? I've tried simply baking the motion but that doesn't deliver anything useful.

10-30-2009, 05:10 PM
Ahh.. Hard FX-it's displacement plug-in class, so it's only affecting points, and leaves motion position/rotation/scale intact.. Even if it's working on entire object, without breaking object to parts.. In theory, somebody can take 1st point position (Dpont's have Point Info node?) and calculate offset from item center to that point and store in Motion's position (all in motion node editor). Then use above described motion baking technique.

Alternatively, you can try using something instead Hard FX that will be motion modifier. I think there was something 3rd party in 3D Party forum and/or Feature Requests. You will surely find it, just use sorting from beginning, it had 3000, or even 5000 views..

10-30-2009, 06:25 PM
For step 4. Last tab within the HardFX. Chose what cube at 'EditNode' at the top and bake motion to null using Commands>MakePath at the bottom. You'll have to parent yourself.

10-30-2009, 09:12 PM
Thank you both for your responses. Everything is sorted now, and you've collectively saved me a lot of manual keyframing. Gracias.