[Plplot-cvs] plplot/src plot3d.c,1.57,1.58

[Alan W. I. <ai...@us...>]

Update of /cvsroot/plplot/plplot/src
In directory sc8-pr-cvs1.sourceforge.net:/tmp/cvs-serv5138

Modified Files:
	plot3d.c 
Log Message:
Bug fix for shade_triangle: deal properly with case where all points are
clipped from triangle by calls to plP_clip_poly.


Index: plot3d.c
===================================================================
RCS file: /cvsroot/plplot/plplot/src/plot3d.c,v
retrieving revision 1.57
retrieving revision 1.58
diff -u -d -r1.57 -r1.58
--- plot3d.c	11 Apr 2004 23:56:49 -0000	1.57
+++ plot3d.c	12 Apr 2004 05:02:02 -0000	1.58
@@ -231,20 +231,22 @@
   n = plP_clip_poly(n, V, 2,  1, -zmin);
   n = plP_clip_poly(n, V, 2, -1,  zmax);
 
-  for(i=0; i<n; i++) {
-    u[i] = plP_wcpcx(plP_w3wcx(x[i], y[i], z[i]));
-    v[i] = plP_wcpcy(plP_w3wcy(x[i], y[i], z[i]));
-    }
-  u[n] = u[0];
-  v[n] = v[0];
+  if(n > 0) {
+     for(i=0; i<n; i++) {
+	u[i] = plP_wcpcx(plP_w3wcx(x[i], y[i], z[i]));
+	v[i] = plP_wcpcy(plP_w3wcy(x[i], y[i], z[i]));
+     }
+     u[n] = u[0];
+     v[n] = v[0];
 
 #ifdef SHADE_DEBUG /* show triangles */
-  plcol0(1);
-  x[3]=x[0]; y[3]=y[0]; z[3]=z[0];
-  plline3(4,x,y,z);
+     plcol0(1);
+     x[3]=x[0]; y[3]=y[0]; z[3]=z[0];
+     plline3(4,x,y,z);
 #else /* fill triangles */
-  plP_fill(u, v, n+1);
+     plP_fill(u, v, n+1);
 #endif
+  }
 }
 
 /*--------------------------------------------------------------------------*\