-
Making a pie chart with expressions
Hi everyone,
I’m in need of some assistance finetuning the controls for a pie chart.
So here’s the deal:
I made a pie chart in AE using circular shapes of different colors. I animate them on with a radial wipe; very fancy indeed 🙂
Because I am going to be using these pie charts a lot, I decided to bundle the controls in a null with slider controls linked to the animation completion for each slice of the pie. All works well except for one thing!
I want the slices to animate in, in a clockwise fashion. To achieve this with a radial wipe, you need to set the animation to counterclockwise and reverse animate. So for instance if you want to animate to a 25% slice of the pie, you need to keyframe the transition completion from 100% to 75%. This is in itself not a huge problem, but I would like my sliders to correspond with the percentages of the slices. Sometimes we work with decimal numbers etc. and it’s annoying to have to have a calculator handy everytime I make a pie chart.
So in a nutshell, what expression do I use to make my slider values correspond to the opposite numbers in the radial wipe.
So:
slider value 0 = transition completion 100
slider value 1 = transition completion 99
slider value 2 = transition completion 98
slider value 3 = transition completion 97Help would be greatly appreciated !!!! And if you have the time to explain why your sollution works, that would also be great! (see attachted image https://www.dropbox.com/s/rqkzi7tgjow138e/Untitled1.jpg )
-
5 Replies
-
100-effect(“Slider Control”)(“Slider”).value;
Normally you should bound the resulting value to [0, 100] but no need since the completion property deals with it.
Xavier.
-
Awesome. Works like a charm!
About bounding the resulting value: is that why you added the .value; ? Because the expression works without it in this instance.
How would you bound the value if you wanted slider 100 to correspond to completion 50%. Not that I want that but just curious to see what the code is to do that.Thanks a lot!
-
The .value is useless indeed.
By bounding, i meant make sure that the result of the expression is between 0 and 100 (because completion is a number 0 and 100) but the effect takes care of it so there is nothing to do.Now for the other part, it depends what you actually want to do. Specifying slider=100 <==> completion=50 is not enough to write the expression… if you also specify slider=0 <==> completion=100, and that the values vary linearly, then :
Math.max(100-0.5*slider, 50);
(slider<=0 : 100, slider>=100: 50).
-
A generally easier method for creating these sorts of relationships is the linear() function, which takes a variable, it’s lower and upper bounds, and the values you want the function to return when the variable trashed those bounds. So, for example:
x = effect("Slider Control")("Slider");
linear(x, 0, 100, 100, 50);When x is 0 this will return 100, when x is 100 it’ll return 50.
Darby Edelen
-
I think “trashed” was supposed to be “reaches” auto correct was punishing me for posting from my phone.
Darby Edelen
Reply to this Discussion! Login or Sign Up