Constant Velocity Along a Curve - Matinee

Hi there,

I’ve been trying to figure something out for a while now and nobody seems to know the answer.

I’m trying to move a camera along a curved path in matinee. However, no matter what I try, the camera movement will change velocity (usually easing in and out at each control point) as it traverses the curve.

Is there any way to force the movement of the camera to have a constant velocity over the distance?

For instance, I would like the camera to move along an arc over 5 seconds… but at a constant velocity over those five seconds.

The only method that I’ve been able to get to (somewhat) work is to child the camera to a target point and then rotate the target point 90 degrees over four evenly spaced keyframes. This is not ideal as I would like to be able to do more than just circular movement. Also, once you detach the camera from the target point, the matinee uses the local position and the camera just stays still (I was hoping that I could create the curve and then use it elsewhere).

Just to be clear, have you set the keyframes to be linear?

If I set the key the keyframes to linear, the path also becomes linear. So the velocity is linear, but the movement path is no longer along a curve.

Unless I’m doing something wrong (which is entirely possible).

The end goal is to have the dots along the curve (in the editor viewport) equidistant between the keyframes. (I hope I’m explaining that well)

I happened to come across this “The Normalize Velocity option modifies a Movement Track’s translation curves in order to make objects traveling along it move at constant velocity.”

This sounds like it might be what I’m looking for but I can’t seem to get the option to appear. I’ve separated the Translation and Rotation tracks, but I can’t locate the option. The documentation doesn’t say anything about where it would be or how to use it.

Sorry, you are right. Linear wouldnt work in this case. To get Normalize Velocity option > Split Translation and Rotation > right click on Movement Track and you’ll see it. I set its start and end to the first and last frames of the animation and the trajectory appears messy in the level but the velocity sems to be constant now. Give it a try and let us know!

Hi Jacky,

That seems to work pretty well. The end keyframes of the section that is normalized gets messed up so that it’s very “jerky” (it actually says this in the documentation), but tweaking them allows for a very nice constant velocity movement along a curve.

Thanks for your help!

No problem! Glad that it works. :slight_smile:

I split the movement track, I still don’t see Normalize Velocity? What panel is it in? Details? Tracks?

Found it, split the tracks - then its under the Movement Track again. Just right click.