Starting point for animated graph

Questions
1

I am currently in a Masters Program and we are working on making Desmos activities and trying to learn a bit about using Computational Layer. This particular question is not necessarily attached to that, but here it is.
I am attempting to use a Ferris Wheel as the introductory tool to periodic functions. I have been able to construct the graph as I want it to and figured out how to use the “try it” button to let the student activate it…My problem is I cannot get my rotating point to start at the bottom of the Ferris Wheel. It is there if looking at the teacher version, but as soon as you go to the “Preview” screen the point jumps up the top. It rotates two revolutions as I intended, I just need to know how to get it to start at the bottom. I am attaching a file with pictures of the teacher screen, the preview screen and of the Graph screen…

FerrisWheel
FerrisWheel.jpg1101×1570 378 KB

Here is the link to the Desmos file itself, in case that is more useful…Just remember this is a work in progress!
[Investigation: Periodic Cycles • Activity Builder by Desmos]

thanks
Chris

2

Looks like you start from pi here whereas timeSincePress starts from 0.
There are two ways you could look at this:

  1. in the graph, make T=t+pi and make t=timeSincePress
  2. in the script:
number("T"):simpleFunction("x+\\pi").evaluateAt(Button.timeSincePress(12.56))