--- ray/src/rt/raytrace.c	1995/01/26 15:34:55	2.19
+++ ray/src/rt/raytrace.c	1995/11/02 17:38:02	2.21
@@ -195,8 +195,11 @@ int  mod;
 			error(USER, errmsg);
 		}
 		******/
-		if ((*ofun[m->otype].funp)(m, r))
-			objerror(r->ro, USER, "conflicting materials");
+		if ((*ofun[m->otype].funp)(m, r)) {
+			sprintf(errmsg, "conflicting material \"%s\"",
+					m->oname);
+			objerror(r->ro, USER, errmsg);
+		}
 	}
 	depth--;			/* end here */
 }
@@ -253,6 +256,21 @@ double  coef;
 	}
 					/* return value tells if material */
 	return(foremat);
+}
+
+
+double
+raydist(r, flags)		/* compute (cumulative) ray distance */
+register RAY  *r;
+register int  flags;
+{
+	double  sum = 0.0;
+
+	while (r != NULL && r->crtype&flags) {
+		sum += r->rot;
+		r = r->parent;
+	}
+	return(sum);
 }