--- ray/src/cv/mgflib/context.c	1995/05/10 17:46:09	1.22
+++ ray/src/cv/mgflib/context.c	1997/12/15 09:41:37	1.26
@@ -1,4 +1,4 @@
-/* Copyright (c) 1994 Regents of the University of California */
+/* Copyright (c) 1997 Regents of the University of California */
 
 #ifndef lint
 static char SCCSid[] = "$SunId$ LBL";
@@ -10,6 +10,7 @@ static char SCCSid[] = "$SunId$ LBL";
 
 #include <stdio.h>
 #include <math.h>
+#include <stdlib.h>
 #include <string.h>
 #include "parser.h"
 #include "lookup.h"
@@ -37,26 +38,26 @@ static LUTAB	mat_tab = LU_SINIT(free,free);	/* materia
 static LUTAB	vtx_tab = LU_SINIT(free,free);	/* vertex lookup table */
 
 				/* CIE 1931 Standard Observer curves */
-static C_COLOR	cie_xf = { 1, C_CDSPEC|C_CSSPEC|C_CSXY|C_CSEFF,
+static C_COLOR	cie_xf = { 1, NULL, C_CDSPEC|C_CSSPEC|C_CSXY|C_CSEFF,
 			{14,42,143,435,1344,2839,3483,3362,2908,1954,956,
 			320,49,93,633,1655,2904,4334,5945,7621,9163,10263,
 			10622,10026,8544,6424,4479,2835,1649,874,468,227,
 			114,58,29,14,7,3,2,1,0}, 106836L, .467, .368, 362.230
 			};
-static C_COLOR	cie_yf = { 1, C_CDSPEC|C_CSSPEC|C_CSXY|C_CSEFF,
+static C_COLOR	cie_yf = { 1, NULL, C_CDSPEC|C_CSSPEC|C_CSXY|C_CSEFF,
 			{0,1,4,12,40,116,230,380,600,910,1390,2080,3230,
 			5030,7100,8620,9540,9950,9950,9520,8700,7570,6310,
 			5030,3810,2650,1750,1070,610,320,170,82,41,21,10,
 			5,2,1,1,0,0}, 106856L, .398, .542, 493.525
 			};
-static C_COLOR	cie_zf = { 1, C_CDSPEC|C_CSSPEC|C_CSXY|C_CSEFF,
+static C_COLOR	cie_zf = { 1, NULL, C_CDSPEC|C_CSSPEC|C_CSXY|C_CSEFF,
 			{65,201,679,2074,6456,13856,17471,17721,16692,
 			12876,8130,4652,2720,1582,782,422,203,87,39,21,17,
 			11,8,3,2,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0},
 			106770L, .147, .077, 54.363
 			};
 				/* Derived CIE 1931 Primaries (imaginary) */
-static C_COLOR	cie_xp = { 1, C_CDSPEC|C_CSSPEC|C_CSXY,
+static C_COLOR	cie_xp = { 1, NULL, C_CDSPEC|C_CSSPEC|C_CSXY,
 			{-174,-198,-195,-197,-202,-213,-235,-272,-333,
 			-444,-688,-1232,-2393,-4497,-6876,-6758,-5256,
 			-3100,-815,1320,3200,4782,5998,6861,7408,7754,
@@ -64,7 +65,7 @@ static C_COLOR	cie_xp = { 1, C_CDSPEC|C_CSSPEC|C_CSXY,
 			8336,8336,8336,8336,8336,8336},
 			127424L, 1., .0,
 			};
-static C_COLOR	cie_yp = { 1, C_CDSPEC|C_CSSPEC|C_CSXY,
+static C_COLOR	cie_yp = { 1, NULL, C_CDSPEC|C_CSSPEC|C_CSXY,
 			{-451,-431,-431,-430,-427,-417,-399,-366,-312,
 			-204,57,691,2142,4990,8810,9871,9122,7321,5145,
 			3023,1123,-473,-1704,-2572,-3127,-3474,-3704,
@@ -72,7 +73,7 @@ static C_COLOR	cie_yp = { 1, C_CDSPEC|C_CSSPEC|C_CSXY,
 			-4066,-4066,-4066,-4066,-4066,-4066},
 			-23035L, .0, 1.,
 			};
-static C_COLOR	cie_zp = { 1, C_CDSPEC|C_CSSPEC|C_CSXY,
+static C_COLOR	cie_zp = { 1, NULL, C_CDSPEC|C_CSSPEC|C_CSXY,
 			{4051,4054,4052,4053,4054,4056,4059,4064,4071,
 			4074,4056,3967,3677,2933,1492,313,-440,-795,
 			-904,-918,-898,-884,-869,-863,-855,-855,-851,
@@ -130,6 +131,7 @@ register char	**av;
 			c_ccname = lp->key;
 			c_ccolor = (C_COLOR *)lp->data;
 			c_ccolor->clock = 0;
+			c_ccolor->client_data = NULL;
 		}
 		i = c_ccolor->clock;
 		if (ac == 3) {		/* use default template */
@@ -177,8 +179,6 @@ register char	**av;
 		if (!isflt(av[1]))
 			return(MG_ETYPE);
 		wsum = atof(av[1]);
-		if (wsum < 0.)
-			return(MG_EILL);
 		if ((lp = lu_find(&clr_tab, av[2])) == NULL)
 			return(MG_EMEM);
 		if (lp->data == NULL)
@@ -188,8 +188,6 @@ register char	**av;
 			if (!isflt(av[i]))
 				return(MG_ETYPE);
 			w = atof(av[i]);
-			if (w < 0.)
-				return(MG_EILL);
 			if ((lp = lu_find(&clr_tab, av[i+1])) == NULL)
 				return(MG_EMEM);
 			if (lp->data == NULL)
@@ -198,6 +196,8 @@ register char	**av;
 					w, (C_COLOR *)lp->data);
 			wsum += w;
 		}
+		if (wsum <= 0.)
+			return(MG_EILL);
 		c_ccolor->clock++;
 		return(MG_OK);
 	}
@@ -248,6 +248,7 @@ register char	**av;
 			c_cmname = lp->key;
 			c_cmaterial = (C_MATERIAL *)lp->data;
 			c_cmaterial->clock = 0;
+			c_cmaterial->client_data = NULL;
 		}
 		i = c_cmaterial->clock;
 		if (ac == 3) {		/* use default template */
@@ -394,6 +395,8 @@ register char	**av;
 				return(MG_EMEM);
 			c_cvname = lp->key;
 			c_cvertex = (C_VERTEX *)lp->data;
+			c_cvertex->clock = 0;
+			c_cvertex->client_data = NULL;
 		}
 		i = c_cvertex->clock;
 		if (ac == 3) {		/* use default template */
@@ -606,10 +609,10 @@ char	**av;
 		}
 		if (n > 1)
 			va[i] /= (double)n;
-		if (va[i] < 0.)
-			return(MG_EILL);
 		if (va[i] > scale)
 			scale = va[i];
+		else if (va[i] < -scale)
+			scale = -va[i];
 	}
 	if (scale <= FTINY)
 		return(MG_EILL);
@@ -667,7 +670,10 @@ double	w1, w2;
 	} else {					/* CIE xy mixing */
 		c_ccvt(c1, C_CSXY);
 		c_ccvt(c2, C_CSXY);
-		scale = 1. / (w1/c1->cy + w2/c2->cy);
+		scale = w1/c1->cy + w2/c2->cy;
+		if (scale == 0.)
+			return;
+		scale = 1. / scale;
 		cres->cx = (c1->cx*w1/c1->cy + c2->cx*w2/c2->cy) * scale;
 		cres->cy = (w1 + w2) * scale;
 		cres->flags = C_CDXY|C_CSXY;