I want to draw the cumulative pot that color is changed

Hello, I'm student. I need to help..

I want to dot using the cumulative of color. I don't khow the fuction for that.

first,

t=1 : the dot rotate drowing the circle

t=2 : also, if second ratating dot pass on the place of the first dot, dot color is changed.! (like under the picture)

so, t=1:5000...

I want to see the cumulative dot plot or contour,

plz, help me..