ray/lib/globe.cal

{
        Coordinate mapping for globe onto unit sphere
        assuming uniform projection of latitude and longitude

        A1 = image height/width
}

globe_u = if(A1-1, 1, 1/A1) * (.5 + Atan2(Py, Px)/(2*PI)) ;

globe_v = if(A1-1, A1, 1) * (1 - Acos(Pz)/PI) ;
Revision:	1.2
Committed:	Tue Mar 18 17:30:17 2003 UTC (21 years, 2 months ago) by greg
Branch:	MAIN
CVS Tags:	HEAD
Changes since 1.1:	+0 -0 lines
State:	*FILE REMOVED*
Log Message:	Decided to move ray/lib directory into non-CVS distribution
#	Content
1	{
2	Coordinate mapping for globe onto unit sphere
3	assuming uniform projection of latitude and longitude
4
5	A1 = image height/width
6	}
7
8	globe_u = if(A1-1, 1, 1/A1) * (.5 + Atan2(Py, Px)/(2*PI)) ;
9
10	globe_v = if(A1-1, A1, 1) * (1 - Acos(Pz)/PI) ;