--- ray/src/common/fvect.h	1997/10/22 14:15:47	2.5
+++ ray/src/common/fvect.h	1998/08/12 17:56:51	2.6
@@ -1,6 +1,6 @@
-/* Copyright (c) 1988 Regents of the University of California */
+/* Copyright (c) 1998 Silicon Graphics, Inc. */
 
-/* SCCSid "$SunId$ LBL" */
+/* SCCSid "$SunId$ SGI" */
 
 #ifdef  SMLFLT
 #define  FLOAT		float
@@ -16,8 +16,18 @@ typedef FLOAT  FVECT[3];
 #define  VCOPY(v1,v2)	((v1)[0]=(v2)[0],(v1)[1]=(v2)[1],(v1)[2]=(v2)[2])
 #define  DOT(v1,v2)	((v1)[0]*(v2)[0]+(v1)[1]*(v2)[1]+(v1)[2]*(v2)[2])
 #define  VLEN(v)	sqrt(DOT(v,v))
+#define  VADD(vr,v1,v2)	((vr)[0]=(v1)[0]+(v2)[0], \
+				(vr)[1]=(v1)[1]+(v2)[1], \
+				(vr)[2]=(v1)[2]+(v2)[2])
+#define  VSUB(vr,v1,v2)	((vr)[0]=(v1)[0]-(v2)[0], \
+				(vr)[1]=(v1)[1]-(v2)[1], \
+				(vr)[2]=(v1)[2]-(v2)[2])
 #define  VSUM(vr,v1,v2,f)	((vr)[0]=(v1)[0]+(f)*(v2)[0], \
 				(vr)[1]=(v1)[1]+(f)*(v2)[1], \
 				(vr)[2]=(v1)[2]+(f)*(v2)[2])
+#define  VCROSS(vr,v1,v2) \
+			((vr)[0]=(v1)[1]*(v2)[2]-(v1)[2]*(v2)[1], \
+			(vr)[1]=(v1)[2]*(v2)[0]-(v1)[0]*(v2)[2], \
+			(vr)[2]=(v1)[0]*(v2)[1]-(v1)[1]*(v2)[0])
 
 extern double  fdot(), dist2(), dist2lseg(), dist2line(), normalize();