View Full Version : Moving at a fixed rate

Steve Warner
10 October 2002, 09:42 PM
Hi all,

I've got a path I created in Modeler that my camera needs to follow. I've exported it as a Motion Path and brought it into Layout as the camera's motion. Layout created keyframes where the points in the curve were, however this created really erratic motion, as some segments of the path were longer and some were shorter. I've tried adding points to the path so that the segments (and resulting keyframes) are were evenly spaced, but the motion was still very erratic. Can anyone tell me if there's an easy way to smooth out the motion? I have successfully done it using spline controls in the graph editor, but it took almost a full day to get a simple 10-second camera fly through done. This might be normal, but it seems like there should be an easier way.

Thanks in advance for any help!


10 October 2002, 09:51 PM
in the graph editor you should be able to move when the keys take place and not where. just space them out evenly through time and that should work. I hope.

or add the motion to a null and use follower to move the camera NOT rotate it. Maybe?

10 October 2002, 12:09 AM
Maybe it has to do with either using uniform knots or uniform length. Otherwise I canīt think of anything causing that problem.

Steve Warner
10 October 2002, 12:30 AM
Thanks KOryH. Actually the keyframes are already evenly spaced out, as an 8-point spline creates 8 keyframes, evenly spaced (something like 5 frames apart). The problem is that the distance traveled between Point 1 and Point 2 might be 10 meters, while the distance between Point 2 and Point 3 might be 4 meters. Since the keyframes are evenly spaced (let's say 5 frames apart), my camera has to move 10 meters in the first 5 frames, and then 4 meters in the next 5 frames. That irregularity is what I'm trying to compensate for in an easy manner. I was thinking of something like Worley's Speedlimit, but rather than limiting speed, it would unifiy the velocity to a constant rate.

Here's a pic:

Thanks again for any help,


10 October 2002, 12:35 AM
Have not tried it myself but it might do the trick:

Steve Warner
10 October 2002, 12:38 AM
Thanks Tottebias, I'll try that out! :applause:


Steve Warner
10 October 2002, 12:44 AM
Oh yeah. Well, now we know why it's in beta format. It crashes Lightwave whenever I run it. Doh!

10 October 2002, 12:47 AM
i would suggest next workflow:

you create your motion path spline in modeler, then copy first point of spline to another layer, then create rail extrude along your original spline using "Uniform Length" option... it will generate points only... next lasso select - ctrl+P... and you will have uniformly spaced spline....

Steve Warner
10 October 2002, 12:51 AM
That's an excellent idea, Leftover. It's probably what MrWyatt was referencing as well. Thanks for the tip! I'll give it a shot!


08 August 2003, 07:54 PM
Sorry to pull this old thread out of the dark, but the rail extrude trick saved my day. Thank you very very much Leftover.

08 August 2003, 08:13 PM
Hi Steve,

add the motion modifier "Curve Constraint" (might be a plugin) to your object in the motion options panel. The "Show Curve" custom object makes the curve visible in layout.


Triple G
08 August 2003, 09:19 PM
Originally posted by preludian
Sorry to pull this old thread out of the dark, but the rail extrude trick saved my day. Thank you very very much Leftover.

Hmm....I always wondered if there was an easy way to do seemed like there should I know! Great trick! Thanks, Leftover. :thumbsup:

08 August 2003, 12:49 AM
i belive their is another one, cruise control? you only set the speed, i belive, (sorry i cant check i am not in my computer)

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