main/src/georegression/geometry/UtilEllipse_F64.java
public static Point2D_F64 computePoint( double t , EllipseRotated_F64 ellipse , Point2D_F64 output ) {
		if( output == null )
			output = new Point2D_F64();

		double ct = Math.cos(t);
		double st = Math.sin(t);
		double cphi = Math.cos(ellipse.phi);
		double sphi = Math.sin(ellipse.phi);

		// coordinate in ellipse frame
		double x = ellipse.a*ct;
		double y = ellipse.b*st;

		// put into global frame
		output.x = ellipse.center.x + x*cphi - y*sphi;
		output.y = ellipse.center.y + x*sphi + y*cphi;

		return output;
	}
public static Point2D_F64 computePoint( double t , EllipseRotated_F64 ellipse , Point2D_F64 output ) {
		if( output == null )
			output = new Point2D_F64();

		double ct = Math.cos(t);
		double st = Math.sin(t);
		double cphi = Math.cos(ellipse.phi);
		double sphi = Math.sin(ellipse.phi);

		// coordinate in ellipse frame
		double x = ellipse.a*ct;
		double y = ellipse.b*st;

		// put into global frame
		output.x = ellipse.center.x + x*cphi - y*sphi;
		output.y = ellipse.center.y + x*sphi + y*cphi;

		return output;
	}
Computes the point on the ellipse at location 't', where t is an angle in radians

@param t An angle in radians from 0 to 2*PI
@param ellipse Ellipse
@param output (Optional) point on the ellipse .  Can be null.
@return Point on the ellipse