--- ray/src/cv/mgflib/context.c	1994/06/25 11:55:45	1.8
+++ ray/src/cv/mgflib/context.c	1994/07/01 10:18:38	1.12
@@ -26,8 +26,11 @@ static C_VERTEX		c_unvertex = C_DEFVERTEX;
 
 				/* the current contexts */
 C_COLOR		*c_ccolor = &c_uncolor;
+char		*c_ccname = NULL;
 C_MATERIAL	*c_cmaterial = &c_unmaterial;
+char		*c_cmname = NULL;
 C_VERTEX	*c_cvertex = &c_unvertex;
+char		*c_cvname = NULL;
 
 static LUTAB	clr_tab = LU_SINIT(free,free);	/* color lookup table */
 static LUTAB	mat_tab = LU_SINIT(free,free);	/* material lookup table */
@@ -58,20 +61,21 @@ register char	**av;
 		if (ac == 1) {		/* set unnamed color context */
 			c_uncolor = c_dfcolor;
 			c_ccolor = &c_uncolor;
+			c_ccname = NULL;
 			return(MG_OK);
 		}
 		lp = lu_find(&clr_tab, av[1]);	/* lookup context */
 		if (lp == NULL)
 			return(MG_EMEM);
+		c_ccolor = (C_COLOR *)lp->data;
 		if (ac == 2) {		/* reestablish previous context */
-			if (lp->data == NULL)
+			if (c_ccolor == NULL)
 				return(MG_EUNDEF);
-			c_ccolor = (C_COLOR *)lp->data;
 			return(MG_OK);
 		}
 		if (av[2][0] != '=' || av[2][1])
 			return(MG_ETYPE);
-		if (lp->key == NULL) {	/* create new color context */
+		if (c_ccolor == NULL) {	/* create new color context */
 			lp->key = (char *)malloc(strlen(av[1])+1);
 			if (lp->key == NULL)
 				return(MG_EMEM);
@@ -79,11 +83,14 @@ register char	**av;
 			lp->data = (char *)malloc(sizeof(C_COLOR));
 			if (lp->data == NULL)
 				return(MG_EMEM);
+			c_ccolor = (C_COLOR *)lp->data;
+			c_ccolor->clock = 0;
 		}
-		c_ccolor = (C_COLOR *)lp->data;
+		c_ccname = lp->key;
+		i = c_ccolor->clock;
 		if (ac == 3) {		/* use default template */
 			*c_ccolor = c_dfcolor;
-			c_ccolor->name = lp->key;
+			c_ccolor->clock = i + 1;
 			return(MG_OK);
 		}
 		lp = lu_find(&clr_tab, av[3]);	/* lookup template */
@@ -92,10 +99,7 @@ register char	**av;
 		if (lp->data == NULL)
 			return(MG_EUNDEF);
 		*c_ccolor = *(C_COLOR *)lp->data;
-		c_ccolor->name = lp->key;
-		c_ccolor->clock = 1;
-		if (ac > 4)
-			return(MG_EARGC);
+		c_ccolor->clock = i + 1;
 		return(MG_OK);
 	case MG_E_CXY:		/* assign CIE XY value */
 		if (ac != 3)
@@ -144,6 +148,7 @@ register char	**av;
 					w, (C_COLOR *)lp->data);
 			wsum += w;
 		}
+		c_ccolor->clock++;
 		return(MG_OK);
 	}
 	return(MG_EUNK);
@@ -155,6 +160,7 @@ c_hmaterial(ac, av)		/* handle material entity */
 int	ac;
 register char	**av;
 {
+	int	i;
 	register LUENT	*lp;
 
 	switch (mg_entity(av[0])) {
@@ -164,20 +170,21 @@ register char	**av;
 		if (ac == 1) {		/* set unnamed material context */
 			c_unmaterial = c_dfmaterial;
 			c_cmaterial = &c_unmaterial;
+			c_cmname = NULL;
 			return(MG_OK);
 		}
 		lp = lu_find(&mat_tab, av[1]);	/* lookup context */
 		if (lp == NULL)
 			return(MG_EMEM);
+		c_cmaterial = (C_MATERIAL *)lp->data;
 		if (ac == 2) {		/* reestablish previous context */
-			if (lp->data == NULL)
+			if (c_cmaterial == NULL)
 				return(MG_EUNDEF);
-			c_cmaterial = (C_MATERIAL *)lp->data;
 			return(MG_OK);
 		}
 		if (av[2][0] != '=' || av[2][1])
 			return(MG_ETYPE);
-		if (lp->key == NULL) {	/* create new material context */
+		if (c_cmaterial == NULL) {	/* create new material */
 			lp->key = (char *)malloc(strlen(av[1])+1);
 			if (lp->key == NULL)
 				return(MG_EMEM);
@@ -185,11 +192,14 @@ register char	**av;
 			lp->data = (char *)malloc(sizeof(C_MATERIAL));
 			if (lp->data == NULL)
 				return(MG_EMEM);
+			c_cmaterial = (C_MATERIAL *)lp->data;
+			c_cmaterial->clock = 0;
 		}
-		c_cmaterial = (C_MATERIAL *)lp->data;
+		c_cmname = lp->key;
+		i = c_cmaterial->clock;
 		if (ac == 3) {		/* use default template */
 			*c_cmaterial = c_dfmaterial;
-			c_cmaterial->name = lp->key;
+			c_cmaterial->clock = i + 1;
 			return(MG_OK);
 		}
 		lp = lu_find(&mat_tab, av[3]);	/* lookup template */
@@ -198,10 +208,7 @@ register char	**av;
 		if (lp->data == NULL)
 			return(MG_EUNDEF);
 		*c_cmaterial = *(C_MATERIAL *)lp->data;
-		c_cmaterial->name = lp->key;
-		c_cmaterial->clock = 1;
-		if (ac > 4)
-			return(MG_EARGC);
+		c_cmaterial->clock = i + 1;
 		return(MG_OK);
 	case MG_E_RD:		/* set diffuse reflectance */
 		if (ac != 2)
@@ -272,6 +279,7 @@ c_hvertex(ac, av)		/* handle a vertex entity */
 int	ac;
 register char	**av;
 {
+	int	i;
 	register LUENT	*lp;
 
 	switch (mg_entity(av[0])) {
@@ -281,20 +289,21 @@ register char	**av;
 		if (ac == 1) {		/* set unnamed vertex context */
 			c_unvertex = c_dfvertex;
 			c_cvertex = &c_unvertex;
+			c_cvname = NULL;
 			return(MG_OK);
 		}
 		lp = lu_find(&vtx_tab, av[1]);	/* lookup context */
 		if (lp == NULL)
 			return(MG_EMEM);
+		c_cvertex = (C_VERTEX *)lp->data;
 		if (ac == 2) {		/* reestablish previous context */
-			if (lp->data == NULL)
+			if (c_cvertex == NULL)
 				return(MG_EUNDEF);
-			c_cvertex = (C_VERTEX *)lp->data;
 			return(MG_OK);
 		}
 		if (av[2][0] != '=' || av[2][1])
 			return(MG_ETYPE);
-		if (lp->key == NULL) {	/* create new vertex context */
+		if (c_cvertex == NULL) {	/* create new vertex context */
 			lp->key = (char *)malloc(strlen(av[1])+1);
 			if (lp->key == NULL)
 				return(MG_EMEM);
@@ -302,11 +311,13 @@ register char	**av;
 			lp->data = (char *)malloc(sizeof(C_VERTEX));
 			if (lp->data == NULL)
 				return(MG_EMEM);
+			c_cvertex = (C_VERTEX *)lp->data;
 		}
-		c_cvertex = (C_VERTEX *)lp->data;
+		c_cvname = lp->key;
+		i = c_cvertex->clock;
 		if (ac == 3) {		/* use default template */
 			*c_cvertex = c_dfvertex;
-			c_cvertex->name = lp->key
+			c_cvertex->clock = i + 1;
 			return(MG_OK);
 		}
 		lp = lu_find(&vtx_tab, av[3]);	/* lookup template */
@@ -315,10 +326,7 @@ register char	**av;
 		if (lp->data == NULL)
 			return(MG_EUNDEF);
 		*c_cvertex = *(C_VERTEX *)lp->data;
-		c_cvertex->name = lp->key
-		c_cvertex->clock = 1;
-		if (ac > 4)
-			return(MG_EARGC);
+		c_cvertex->clock = i + 1;
 		return(MG_OK);
 	case MG_E_POINT:	/* set point */
 		if (ac != 4)
@@ -361,6 +369,18 @@ c_clearall()			/* empty context tables */
 }
 
 
+C_MATERIAL *
+c_getmaterial(name)		/* get a named material */
+char	*name;
+{
+	register LUENT	*lp;
+
+	if ((lp = lu_find(&mat_tab, name)) == NULL)
+		return(NULL);
+	return((C_MATERIAL *)lp->data);
+}
+
+
 C_VERTEX *
 c_getvert(name)			/* get a named vertex */
 char	*name;
@@ -526,5 +546,4 @@ double	w1, w2;
 		cres->cy = (w1 + w2) * scale;
 		cres->flags = C_CDXY|C_CSXY;
 	}
-	cres->clock++;			/* record the change */
 }