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hlinldey
05-19-2005, 01:49 AM
Hi, I have a rather large environment with a road winding around small hills. I projected an offset curve onto the surface of the road and attached a motorcycle to that projected curve as a motion path. Everything works great, but the motion path animation is really jerky. It will pause for a few frames and then jerk both forwards and backwards along the path. I thought it was just the viewport slowing down trying to keep up, but a playblast shows the same behavior.

I have tried rebuilding the curve several different ways and I have tried setting the motion path to parametric, but the jerkyness persists.

The path itself is comprised of many, many points and the path animation goes from 0 to 9000 frames if that helps the diagnosis.

Thanks in advance for any help!
hlinldey
05-19-2005, 08:03 PM
bump, anyone ever experienced this?
crazymovies
02-08-2006, 10:34 PM
bump, anyone ever experienced this?

how did you create a motion path? i need to know

thanks
ruddiger52
02-09-2006, 01:49 AM
Using your original path extrude a nurbs surface along it so you bascially have a ribbon like plane following the direction of path. Delete the original curve. You might be able to see the problem areas in the surface, if not no worries. If you do see problems smooth them out to your liking. Now make the surface live. Using the EP curve tool make a curve down the center of the surface by curve constrain clicking once at each end of the surface. You should have a curve similar to your original. Now make the surface not live and hide the surface. Attach your character to the path with "World up" type set to "normal". This will make sure your character will orient to the surface's original normals and eliminate random rotating. You will still have to set your front axis and up axis to suit your needs. I had a project where i had a camera following a long windy path and this is how i fixed.
FloydBishop
02-09-2006, 02:28 AM
It may be the settings you used when you set the object on the motion path. If you use "parametric", it will cause the object to move at different rates based upon what is happening with the distance from point to point.

It sounds like this could be your problem.
crazymovies
02-09-2006, 02:34 AM
Using your original path extrude a nurbs surface along it so you bascially have a ribbon like plane following the direction of path. Delete the original curve. You might be able to see the problem areas in the surface, if not no worries. If you do see problems smooth them out to your liking. Now make the surface live. Using the EP curve tool make a curve down the center of the surface by curve constrain clicking once at each end of the surface. You should have a curve similar to your original. Now make the surface not live and hide the surface. Attach your character to the path with "World up" type set to "normal". This will make sure your character will orient to the surface's original normals and eliminate random rotating. You will still have to set your front axis and up axis to suit your needs. I had a project where i had a camera following a long windy path and this is how i fixed.


that doesnt answer my question, i need ot know from the very begining how to create a motion path. and how to animate/move things in shake.

thanks so much
jdonnelly
02-09-2006, 07:36 PM
I tried using your suggestion for a project I'm working on, but when I try to attach my object to the path I get an error message saying "Cannot parent curve in the underworld" ?????

I'm using a spline IK and trying to use the curve of the path instead of auto creating one for the joints.

Is there a way to duplicate the curve I made on the surface so it becomes its own seperate thing?
jdonnelly
02-09-2006, 07:50 PM
ah ha. I got it... All I had to do was goto "Edit Curves->Duplicate Surface Curves"

Now its an actual, existing curve that I can use for whatever.

Oh, and before all this stuff, after you've created your "ribbon". Make sure that the ribbon surface is parallel to the floor (ie, if it were lying on a table, it'd be flat... not standing up on edge)

This was you can see how messed up the normals are and twist the CV's to make them all pointing in one direction.
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