find center / noob question

OpenGL OpenGL: Basic Coding
1

hi all,

noob here

lets say you have a planet in orbit

is there a way to get the coordinates of the center of the planet as its rotating?

thanks :slight_smile:

2

yes
if it is rotating in a simple circle then
X = r * cos (theta)
Y= r*sin(theta)
if it is rotating in an arbitrarily located ellipse things get a bit trickier, but not much. In this case define vectors a and b to be the major and minor axis. Then p = a cos (theta) + b sin(theta)