How to Get 2 Fruity Formula Controllers to Move Together in an Ellipse/Circle Over Time

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Fruity Formula Controller in FL Studio can auto-modulate controls for any VSTi, you can link 2 formula controllers to any X/Y pad parameters in a VSTi (one to the X parameter and one to the Y parameter) and cause the pad control to automatically move in an ellipse or circle with varying center, width and height, and speed. Not sure if someone else already figured this out and posted it, but I couldn't find anything on it in manuals or using search engines here or elsewhere, so I took some time to figure it out because sometimes I just want to automate an XY pad in a slow circle (or ellipse or semicircle) to continuously morph a sound smoothly. Here's what I came up with and it works a treat (tried it on the XY morph pad in FM8), maybe it will help someone else too. It's based on the parametric equation for the unit circle using time as the parameter; you can modify the formulae below for other types of patterns as well if you know their parametric equations.

In this case, you would put two formula controllers into the effects section for the VSTi you want to modulate.
Then left click the dropdown arrow in the upper left corner of the plugin (this is part of the fruity wrapper), choose "browse parameters", and find the parameter you want to modulate with the first formula controller (it might be called "morph X" or something like); right-click it, choose "link to controller", then drop down the "internal controller" list, choose the 1st value for "formula ctrl...", and accept. Then do the same thing for the second parameter you want to modulate, but choose the 2nd value for "formula ctrl...".
Then put in the formulae below in the formula controller effects:

X parameter formula = a+b/2*sin(time*c/100)
Y parameter formula = a+b/2*cos(time*c/100)

then the a, b and c dials in each Formula Controller will change:
a = ellipse center
b = range (ellipse width for X, ellipse height for Y)
c = speed

The XY pad controller will move around clockwise

note that to get a perfect circle:
both a values must be set to 50% (center of pad)
both b values must match
both c values must match

I like a full-sized, slow-moving circle for which you would set both controllers to:
a=50% (middle), b=100% (max), c=1%

to get a simple lissajous figure for example (which will actually get into the corners whereas the circle does not), with the same controls as above, use this slightly modified formula instead:
X parameter formula = a+b/2*sin(2*time*c/100)
Y parameter formula = a+b/2*cos(3*time*c/100)