Trim Path on Grouped Shape Layers

[chairmanmao]

I have a 3D extruded line, created in Illustrator, that I'm trying to animate in AE. I successfully created shape layers from the vector objects in the imported Illustrator file. The converted line is curved, with shading.

What I'm trying to do is use Trim Paths to show the line growing over time, from one side of the view to the other.

The problem I'm running into is twofold. First, Trim Paths is not progressively "revealing" the line. Instead, it seems like it's repositioning the last point of the curve, and progressively filling it in. This creates some odd shapes in the early stages of the reveal. Second, the shaded "underside" shape was broken into two pieces during the import process, and the reveal starts from the left-hand sides of both pieces.

Is there a way to merge the various shape layers so that they act as a single unit? I've tried grouping them, but that doesn't solve the problem; each element of the group retains its individual identity so far as Trim Paths is concerned.

Would I be better off throwing out the imported curved/extruded line and trying to recreate it in AE?

[Rick Gerard]

For trim paths, your shape layers can contain no fills. If you applied a brush or an effect to a line in AI you will get a closed path with a fill when you convert the vector layer to a shape. Spin down the layer properties and delete or turn off any fill and see if that is the problem.

If that is not the problem then I need a screenshot. I use AI to create paths that I can use Trim Paths on, but you have to be extremely careful with your design the artwork to avoid problems.

If getting rid of the fills, fixing closed paths, and rearranging the groups and paths doesn't fix the problem we need a screenshot with the modified properties of the layers giving you problems revealed. Just press UU, PrintScreen and Paste to the forum.

[Mylenium]

Wrong workflow. Don't even bother with using fancy stuff in AI, just import the plain paths. You can always re-create any shading using other techniques. if that's not an option, then don't bother to convert your vectors to shapes and use conventional pixel-based reaveal techniques using effects, wipes, mattes and masks.

Mylenium

[chairmanmao · Accepted solution]

Thanx to both of you, you gave me ideas that led to a solution.

One part involved using a subtractive mask layer as the basis for a simple animated wipe (by redefining the mask rectangle at the starting and ending key frames).

The other part involved simply creating a movement path by dragging an object after setting start and end keyframes for the motion. The trick there was first relocating the object’s anchor point using the pan behind tool to the center of the object (importing from Illustrator had placed the anchor somewhere else). Centering the anchor point made it easier to trace the object’s path along the curved line. A couple of tweaks to the motion path with the pen tool and I’d mimicked the curve of the line itself. Syncing the wipe with the motion, and adding a slight rotation to the arrowhead so it would point along the line and I had the animation I wanted.