I have a map of individual trees from a forest stored as x,y points in a matrix. I call it fixedPositions. It's cartesian and (0,0) is the origin.

I would like 0/360 degrees to be the top of the screen and 90 degrees to be to the right.

Given a velocity and a heading, i.e. .5 m/s and 60 degrees (2 o'clock equivalent on a watch), how do I rotate that x,y points, so that the new origin is centered at (.5cos(60),.5sin(60)) and 60 degrees is now at the top of the screen?

Then if I were to give you another heading and speed, i.e. 0 degrees and 2m/s, it should calculate it from the last point, not the original fixedPositions origin.

I've wasted my day trying to figure this out. I wish I took matrix algebra but I'm at a loss.

I tried doing cos(30) and even those wouldn't compute correctly, which after an hour I realize were in radians.