{ SCCSid "$SunId$ LBL" } { Source distribution coordinates (degrees). Theta is measured from the negative z-axis, phi is measured from the positive x-axis according to the right-hand rule. srcB_vert and srcB_horiz are angles used in type B photometry. boxcorr function corrects for distribution modeled with a rectangular box. lboxcorr provides a more accurate calculation for nearby surfaces, but requires that the source box be centered at the origin. A1 - optional multipier A2,A3,A4 - X,Y,Z dimensions of axis-aligned box } { local definitions } norm_deg(d) : if( d, d, d+360 ); boxprojection = abs(Dx)*A3*A4 + abs(Dy)*A2*A4 + abs(Dz)*A2*A3; lboxprojection = ( noneg(abs(Px-Dx*Ts)-A2/2)*A3*A4 + noneg(abs(Py-Dy*Ts)-A3/2)*A2*A4 + noneg(abs(Pz-Dz*Ts)-A4/2)*A2*A3 ) / Ts; flatcorr(v) = corr(v) / Rdot; { correction for flat sources } corr(v) = if(AC-.5, A1*v, v); { multiplier correction } boxcorr(v) = A1 * v / boxprojection; { correction for emitting box } lboxcorr(v) = A1 * v / lboxprojection; { local box correction } src_theta = Acos(Dz) / DEGREE; { 0-180 } src_phi = norm_deg( atan2(Dy, Dx) / DEGREE ); { 0-360 } { bilateral symmetry } src_phi2 = tri( src_phi, 180 ); { 0-180 } { quadrilateral symmetry } src_phi4 = tri( src_phi, 90 ); { 0-90 } { Type B photometry coordinates } srcB_vert = atan( -Dx/Dz ) / DEGREE; srcB_horiz = Asin(Dy) / DEGREE; { w/ bilateral symmetry } srcB_horiz2 = abs( srcB_horiz );