From info-iris-request -8 at 8- vmb.brl.mil Fri Jun 14 13:27:35 1991 Date: 14 Jun 91 14:55:43 GMT From: Don Sosoka Organization: NASA/Lewis Research Center, Cleveland Subject: lighted, multi-colored polys To: info-iris ":at:" BRL.MIL Status: R I know this should be an easy one and the answer must be docummented some- where but I can't find it. Please Help! I want to draw smooth (GOURAUD) shaded lighted polygons starting with different colors at each vertex. Assuming the lighting model is setup correct (which it seems to be), if I do something like call SHADEM (GOURAU) call BGNPOL do 10 i = 1,N vn(1) = XN(i) vn(2) = YN(i) vn(3) = ZN(i) call N3F (vn) icv(1) = IRED(i) icv(2) = IGREEN(i) icv(3) = IBLUE(i) call C3I (icv) v(1) = X(i) v(2) = Y(i) v(3) = Z(i) call V3F (v) 10 continue call ENDPOL I get smooth shaded colored polygons but no lighting effects. If I reverse the order: call SHADEM (GOURAU) call BGNPOL do 10 i = 1,N icv(1) = IRED(i) icv(2) = IGREEN(i) icv(3) = IBLUE(i) call C3I (icv) vn(1) = XN(i) vn(2) = YN(i) vn(3) = ZN(i) call N3F (vn) v(1) = X(i) v(2) = Y(i) v(3) = Z(i) call V3F (v) 10 continue call ENDPOL I get a nicely lit surface but all gray shaded. What's the trick? (or am I way off base). Thank's.