Auto-resize of shapes driven by one shape

[Walter Soyka]

My first approach would be to add controls for the dividers or the intersection points and animate those. Write expressions for the shape layers that derive the correct size and position of each one from the controls in the rig.

Walter Soyka
Principal & Designer at Keen Live
Motion Graphics, Widescreen Events, Presentation Design, and Consulting
RenderBreak Blog – What I’m thinking when my workstation’s thinking
Creative Cow Forum Host: Live & Stage Events

[Matt Comradski]

Thanks for your input Walter, but I have no idea how to do what you proposed. Do you have specific examples/instructions to create controls for dividers? How would you do that? Also, the expression tip seems too complex for my level of coding. Again, if you have an example of what you mean, I would really appreciate some elaboration.

Thanks

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Redpandavfx

[Walter Soyka]

[Matt Comradski] “Thanks for your input Walter, but I have no idea how to do what you proposed.”

If you want to automate this, then I think you’re going to have to learn some expressions. You can try the After Effects Expressions forum [link], but honestly, setting this up would be a couple hours’ work, and describing it all step-by-step is well beyond the scope I’d ordinarily address in a free forum post for free. You might have to consider hiring it out to a geek like me if there’s not already something “off the shelf.”

But I’m not trying to give you the hard sell, so I’ll get you started on what I’d look to do in case you want to do some more research and tackle this yourself.

[Matt Comradski] “Do you have specific examples/instructions to create controls for dividers?”

Yes, I’d use Slider Control effects applied to a null (located in the Expression Controls category). These sliders could be animated in the effects control panel or in the timeline, and the expressions for the shape layers would refer back to them.

[Matt Comradski] “Also, the expression tip seems too complex for my level of coding. Again, if you have an example of what you mean, I would really appreciate some elaboration.”

If you put a rectangle and fill on on a shape layer, it has some special properties including size (different than scale) and transform (separate from the layer’s transform). You can use these to control how big the shape is and where it is located on screen; a pair of expressions in these values linking back to the divider controls can dictate where the shape appears. The transform would have to put the center of the shape half way between both the vertical and horizontal dividers that define it, and the size would have to match the distance between the dividers.

A separate non-expression approach might be to manually animate a set of overlapping shape layers, each with a different luminance value (i.e., they range in even steps from full black to full white). You can use the layer order creatively to mitigate the amount of manual keyframing you’ll have to do.

Then you could precomp them, duplicate the layer as many times as necessary, and use the Extract effect to pull a luma key, isolated to a single shape. You could use this layer (precomp plus Extract) as an alpha matte for whatever you actually want to appear.

Walter Soyka
Principal & Designer at Keen Live
Motion Graphics, Widescreen Events, Presentation Design, and Consulting
RenderBreak Blog – What I’m thinking when my workstation’s thinking
Creative Cow Forum Host: Live & Stage Events