# And a Thank You hat tip to Professor Mellin

I wanted to give kudos to Mellin for his circular motion formulas which I’ve used on two of my faces:

(((sin(((t+xa)/180)*pi))*xr)+x) on the x-axis
(((cos(((t+ya)/180)*pi))*yr)+y) on the y-axis

I’ve had some interesting fun with these formulas…
On my Apertures face, the minute value (the text only) runs around the face perimeter using these two formulas because text fields are not like images with rotation features. I needed the minute value to orbit in concert with the small chrome medallion that follows the outer groove. The challenge here is that the center of text is not necessarily in the center of the space it occupies. In short, text at x=160, y=160 is not centered. So I had to keep tweaking the placements in the formulas (center and radius) until the minutes were centered in the medallion at 12:00 and 6:00 and again at 3:00 and 9:00.

On my Thumper face, I’m using the same formulas to keep all of the values on the perimeter of the speaker. So the values go around using the sine & cosine placements but then the text (and tiny images) have to also rotate so they stay placed on the outer rim. So in the case of the daily steps for example:
x-axis = (((sin((((360-#DWFSS#)+45)/180)*pi))*140)+160)
y-axis = (((cos((((360-#DWFSS#)+45)/180)*pi))*140)+160)
and then the complementary rotation = (#DWFSS#+135), that is 90-degrees orthogonal to the circular motion.

Thanks again Professor Mellin!
John

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You did good kid.
Class dismissed!

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Ha ha, I want to be your student too…