Tweaking a shape on a path.

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NealF
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Tweaking a shape on a path.

Post by NealF »

Hi.

I'm trying to create an arrow that has a starting point and grows along a path. I've got it figured out that I can create the path, stroke it, then expose it over time to look like it's growing from zero to a full arrow.

Then I created another shape for the arrow head. I learned how to make that shape follow the path. But here's the problem.

1. Even though it's working, the path the head is following is off to the side of the path I linked it to.
2. I can't seem to get the tip of the arrow head to face the direction it's going.

At some point I saw the actual path the arrow head was following. Don't remember how I did it, but it was obviously not the original path, but one that was the same shape but along side it.

So how can I tweak the path that it's on to be identical to the path I linked it to, and how can I get the arrow head to face the right direction.

Thanks.
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NealF
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Re: Tweaking a shape on a path.

Post by NealF »

I got it figured out to some extent.

When I'm past frame one and have the layers tool selected I can see the path and pull and stretch it to match what I want better.

Also, at frame zero I can move the layer into position so it corresponds with the path.

Takes a lot of tweaking to make it work, but it seems to be okay now.
All except for the nose of the arrow head facing the direction it's going. I just turned off that option and tweak it manually.
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hayasidist
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Re: Tweaking a shape on a path.

Post by hayasidist »

the layer that follows the path: put the arrowhead so the tip is upwards exactly on the y axis with the rest symmetrically below it. If you then set the shape's origin to {0,0} (manually enter the coordinates) that will stop it being off to one side of followed path. Choose the path to follow and then check the "rotate to follow path" option in the layer settings of the arrowhead to make it faithfully follow the path. The easiest way to make sure the path exposes in sync with transit of the arrowhead is to use linear interpolation for both. Depending exactly on how you draw the arrowhead you may need to make a final adjustment of the shape's position on frame 0 so, e.g. move all the points so the tip of the arrow starts where you want it on the followed path and adjust the path exposure start and end percentages.

hth
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NealF
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Re: Tweaking a shape on a path.

Post by NealF »

Thanks for that detailed explanation. I'll be trying it out shortly.
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