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# Creating a stroke-able slice with a Shape Layer

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 Creating a stroke-able slice with a Shape Layer on Nov 30, 2011 at 1:11:27 am

Hi,

I'm trying to figure out a simple way of creating a wedge of a circle to which I can then apply a fill and a stroke. But the wedge needs to be expandable so I can adjust the degrees from 0 degrees to 360 degrees. Imagine a slice of a pie chart that starts as a minute sliver representing 1% and then expands to represent 100% .

I have tried using a bunch of half circle shapes (full circles whose paths are trimmed to 50%) and then merging them but that get's messy when you get close to 360 because I had to do a bunch of rotations on rotations. Also, you can't stroke them. I tried using two triangle polystars and a circle but that also requires multiple triangles and rotations which gets messy again.

Any help is greatly appreciated!

Thanks,
-Josh

 Re: Creating a stroke-able slice with a Shape Layeron Nov 30, 2011 at 1:49:46 am

[Josh Kurz] "I'm trying to figure out a simple way of creating a wedge of a circle to which I can then apply a fill and a stroke. But the wedge needs to be expandable so I can adjust the degrees from 0 degrees to 360 degrees. Imagine a slice of a pie chart that starts as a minute sliver representing 1% and then expands to represent 100%"

You could use a circle shape layer with a Radial Wipe effect [link] and a Stroke layer style [link].

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

 Re: Creating a stroke-able slice with a Shape Layer (now OT: Pac Man)on Nov 30, 2011 at 1:59:50 am

On a less serious note, I'd like to expand a bit on my previous post.

70% of all pie charts resemble Pac Man. If you'd rather use this to make Pac Man than a boring pie chart, throw this expression on the Radial Wipe effect's Start Angle property:

```startAngle = effect("Radial Wipe")("Start Angle"); transitionPercent = effect("Radial Wipe")("Transition Completion"); transitionDegrees = transitionPercent * 360 / 100; startAngle - transitionDegrees/2;```

Animate the Transition Completion (the perfect application for loopOut("pingpong")) to make the mouth open and close, and animate the Start Angle to rotate Pac Man.

Cheers,

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

 Re: Creating a stroke-able slice with a Shape Layer (now OT: Pac Man)on Dec 1, 2011 at 4:17:58 pm

Another nifty way to animate a pie chart if you want to have multiple slices of pie:
Apply a horizontal grayscale ramp to a solid, followed by a rectangular to polar coordinates conversion, followed by colorama. If you uncheck "Interpolate Palette" in the output cycle of colorama, you can create any number of colored pie wedges. By key framing the output cycle, you can easily animate between different versions of the pie chart.

Cheers,
-Matt

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