Objects animate strangely after moving keyframe


Thank you to all the people who have helped make this wonderful program. I am working hard to learn it well.

Problem… I have found that if I have a basic animation, then alter the waypoints, the value alter in awful ways. eg, if I change the “amount” from 0 to 1 and then move one of those two waypoints then rather than changing from 0 to 1 at a different speed, the value goes from 0 up to say, 1.5, then rests back at 1. Same goes if I move a origin waypoint on the time line, the object overshoots its mark, then comes back to rest in the right spot.

If I make an animation, then make the first and last frames keyframes, I move the keyframes closer together in the hopes of shortening the animation time, which works, but the movements then behave as described above.

I guess my question is two fold, what the heck is actually going on? and how do I change these things without it all going to junk? lol

Thanks! I love synfig… when I can work it :slight_smile:

This is a limitation of the current interpolation methods. TCB does generate overshoots. You’ll have o manually change interpolation types of your waypoints to get around this.

There have been disussions about this before, http://synfig.org/forums/viewtopic.php?f=14&t=1603.
Hopefully we’ll se a new auto-type of keyframes in the future.

Thank you, that was an interesting discussion. So after I fix this one animation would you suggest that I change my default yo “linear” from now on?

In what cases would I really be best to use TCB and how could I change this in TCB without making this happen?

I am right in understanding that I should be able to “squish” waypoints together to shorten a sequence, right?

Thanks again,

Linear is yet another interpolation method where values goes in a straight line from one to the next, the result is quite mechanical. So I wouldn’t recommend you to set this as default.

Unfortunately you cannot do anything by default to avoid this in TCB, you’ll have to manually adjust this afterwards. Either by changing interpolation type for individual waypoints, as setting out-value to linear from a waypoint that overshoots etc. Or you could play with the interpolation values through the waypoint editor.

Yes, you can squish a sequence of waypoints. The trick is to add keyframes one at start and one at end of the sequence you want to rescale. Now you can move the last keyframe closer to the first. All waypoingt between is scaled as they were on a rubber band. Move keyframes by changing the length in the keyframe panel.

lol… that will save a bit of time. I was about to start changing the ins and outs on ALL of them! thnx