--- ray/src/px/clrtab.c	1992/10/13 11:36:20	2.3
+++ ray/src/px/clrtab.c	2003/02/22 02:07:27	2.12
@@ -1,9 +1,6 @@
-/* Copyright (c) 1992 Regents of the University of California */
-
 #ifndef lint
-static char SCCSid[] = "$SunId$ LBL";
+static const char	RCSid[] = "$Id: clrtab.c,v 2.12 2003/02/22 02:07:27 greg Exp $";
 #endif
-
 /*
  * Simple median-cut color quantization based on colortab.c
  */
@@ -23,7 +20,7 @@ static char SCCSid[] = "$SunId$ LBL";
 #define part(cn)	((cn)>>2)
 #define prim(cn)	((cn)&3)
 				/* our color table (global) */
-BYTE	clrtab[256][3];
+extern BYTE	clrtab[256][3];
 				/* histogram of colors / color assignments */
 static unsigned	histo[NRED][NGRN][NBLU];
 #define cndx(c)		histo[((c)[RED]*NRED)>>8][((c)[GRN]*NGRN)>>8][((c)[BLU]*NBLU)>>8]
@@ -32,12 +29,24 @@ static int	CLRCUBE[3][2] = {0,NRED,0,NGRN,0,NBLU};
 				/* maximum propagated error during dithering */
 #define MAXERR		20
 				/* define CLOSEST to get closest colors */
-#define CLOSEST		1
+#ifndef CLOSEST
+#ifdef SPEED
+#if  SPEED > 8
+#define CLOSEST		1	/* this step takes a little longer */
+#endif
+#endif
+#endif
 
+static	cut(), mktabent(), closest(), addneigh(), setclosest();
+static int	split();
+static unsigned	dist();
 
-new_histo()		/* clear our histogram */
+
+new_histo(n)		/* clear our histogram */
+int	n;
 {
 	bzero((char *)histo, sizeof(histo));
+	return(0);
 }
 
 
@@ -71,6 +80,8 @@ int	ncolors;
 #ifdef CLOSEST
 	closest(ncolors);	/* ensure colors picked are closest */
 #endif
+				/* reset dithering function */
+	dith_colrs((BYTE *)NULL, (COLR *)NULL, 0);
 				/* return new color table size */
 	return(ncolors);
 }
@@ -101,16 +112,17 @@ register BYTE	*bs;
 register COLR	*cs;
 int	n;
 {
-	static short	(*cerr)[3];
+	static short	(*cerr)[3] = NULL;
 	static int	N = 0;
 	int	err[3], errp[3];
 	register int	x, i;
 
 	if (n != N) {		/* get error propogation array */
-		if (N)
-			cerr = (short (*)[3])realloc((char *)cerr,
-					3*n*sizeof(short));
-		else
+		if (N) {
+			free((void *)cerr);
+			cerr = NULL;
+		}
+		if (n)
 			cerr = (short (*)[3])malloc(3*n*sizeof(short));
 		if (cerr == NULL) {
 			N = 0;
@@ -175,7 +187,7 @@ register int	box[3][2];
 #define c0	r
 	register int	r, g, b;
 	int	pri;
-	int	t[HMAX], med;
+	long	t[HMAX], med;
 					/* find dominant axis */
 	pri = RED;
 	if (box[GRN][1]-box[GRN][0] > box[pri][1]-box[pri][0])
@@ -231,9 +243,10 @@ mktabent(p, box)	/* compute average color for box and 
 int	p;
 register int	box[3][2];
 {
-	long	sum[3];
-	int	r, g, n;
-	register int	b, c;
+	unsigned long	sum[3];
+	unsigned	r, g;
+	unsigned long	n;
+	register unsigned	b, c;
 						/* sum pixels in box */
 	n = 0;
 	sum[RED] = sum[GRN] = sum[BLU] = 0;
@@ -248,6 +261,12 @@ register int	box[3][2];
 		    }
 		    histo[r][g][b] = p;		/* assign pixel */
 		}
+	if (n >= (1L<<23)/HMAX) {		/* avoid overflow */
+		sum[RED] /= n;
+		sum[GRN] /= n;
+		sum[BLU] /= n;
+		n = 1;
+	}
 	if (n) {				/* compute average */
 		clrtab[p][RED] = sum[RED]*256/NRED/n;
 		clrtab[p][GRN] = sum[GRN]*256/NGRN/n;
@@ -335,7 +354,7 @@ dist(col, r, g, b)		/* find distance from clrtab entry
 register BYTE	col[3];
 int	r, g, b;
 {
-	register unsigned	tmp;
+	register int	tmp;
 	register unsigned	sum;
 	
 	tmp = col[RED]*NRED/256 - r;