-
Flare/stroke moving through a path: how to change speed?
Hi all:
I’m doing an animation with a fairly standard effect: a flare moves following a path, while a stroke effect “paints” that path making it look as if the flare was leaving a trail. I did this by copying the “mask shape” property of the path and pasting it as keyframes in the “position” property of the flare. So far so good, etc.
…Except that now I want the flare to move faster, but only starting from a certain point of the animation. I tried doing this by adding a keyframe for the flare at that point, selecting then the last keyframe and moving it backwards; since they are roving keyframes, this preserves the proportions between all the keyframes, but that segment of the animation moves faster now. In case this hasn’t been clear, let’s see if I can do some ASCII art to explain it better:
BEFORE
X————O———X
AFTER
X————O—X
Where “X” are the first and last keyframe and “O” is the point starting from which the flare should move faster.
The problem is that now that I’ve messed with the keyframes pasted from the path, the Stroke effect is out of sync with the flare, and I don’t really know how to solve it, other than keyframing the Stroke effect by hand (yikes). Has anyone found this problem before? What did you do to solve it?(Really, really, really thanks in advance).
Paulo.
-
3 Replies
-
One of the easier ways to accomplish this might be to use the Write On effect instead, moving the brush point along with the flare.
Otherwise you need to make sure that you add keyframes in the percentage property of the Stroke effect to mirror the changes you’re making in the flare position.
Darby Edelen
Designer
Left Coast Digital
Santa Cruz, CA -
Thanks a lot for your answer! Unfortunately, the layer (and the flare”s movement) is 3D… and Write-On’s brush position seemd to be only 2D. Am I missing something, or is there some other way?
(I’ve just tried another way I just thought of: precompose the flare and the stroke, move the precomp into a new composition and use Time Remap to manipulate the speed. Unfortunately, it didn’t work in my case: the layer where the stroke takes place has a non-standard size (2000×1500), and precomposing it and replacing it with a 720×576 one messes up the camera movements that I had already set up).
Paulo.
-
[Paulo Jan] “Thanks a lot for your answer! Unfortunately, the layer (and the flare”s movement) is 3D… and Write-On’s brush position seemd to be only 2D. Am I missing something, or is there some other way? “
Just a quick note: the stroke effect is limited to a 2D plane as well.
There are expressions that will allow you to project a 3D position onto a 2D plane if you’re still running short on ideas. Something like this on the Brush Position:
l = thisComp.layer("Flare");
fromCompToSurface(l.toComp(l.anchorPoint));Darby Edelen
Designer
Left Coast Digital
Santa Cruz, CA
Reply to this Discussion! Login or Sign Up