--- ray/src/common/color.c	1991/11/12 16:55:34	2.1
+++ ray/src/common/color.c	2003/07/27 22:12:01	2.13
@@ -1,56 +1,59 @@
-/* Copyright (c) 1991 Regents of the University of California */
-
 #ifndef lint
-static char SCCSid[] = "$SunId$ LBL";
+static const char	RCSid[] = "$Id: color.c,v 2.13 2003/07/27 22:12:01 schorsch Exp $";
 #endif
-
 /*
  *  color.c - routines for color calculations.
  *
- *     10/10/85
+ *  Externals declared in color.h
  */
 
+#include "copyright.h"
+
 #include  <stdio.h>
 
+#include  <stdlib.h>
+
+#include  <math.h>
+
 #include  "color.h"
 
 #define  MINELEN	8	/* minimum scanline length for encoding */
+#define  MAXELEN	0x7fff	/* maximum scanline length for encoding */
 #define  MINRUN		4	/* minimum run length */
 
 
 char *
 tempbuffer(len)			/* get a temporary buffer */
-unsigned  len;
+unsigned int  len;
 {
-	extern char  *malloc(), *realloc();
 	static char  *tempbuf = NULL;
-	static int  tempbuflen = 0;
+	static unsigned  tempbuflen = 0;
 
 	if (len > tempbuflen) {
 		if (tempbuflen > 0)
-			tempbuf = realloc(tempbuf, len);
+			tempbuf = (char *)realloc((void *)tempbuf, len);
 		else
-			tempbuf = malloc(len);
+			tempbuf = (char *)malloc(len);
 		tempbuflen = tempbuf==NULL ? 0 : len;
 	}
 	return(tempbuf);
 }
 
 
+int
 fwritecolrs(scanline, len, fp)		/* write out a colr scanline */
 register COLR  *scanline;
 int  len;
 register FILE  *fp;
 {
-	register int  i, j, beg, cnt;
+	register int  i, j, beg, cnt = 1;
 	int  c2;
 	
-	if (len < MINELEN)		/* too small to encode */
+	if ((len < MINELEN) | (len > MAXELEN))	/* OOBs, write out flat */
 		return(fwrite((char *)scanline,sizeof(COLR),len,fp) - len);
-	if (len > 32767)		/* too big! */
-		return(-1);
-	putc(2, fp);			/* put magic header */
+					/* put magic header */
 	putc(2, fp);
+	putc(2, fp);
 	putc(len>>8, fp);
 	putc(len&255, fp);
 					/* put components seperately */
@@ -90,15 +93,53 @@ register FILE  *fp;
 }
 
 
+static int
+oldreadcolrs(scanline, len, fp)		/* read in an old colr scanline */
+register COLR  *scanline;
+int  len;
+register FILE  *fp;
+{
+	int  rshift;
+	register int  i;
+	
+	rshift = 0;
+	
+	while (len > 0) {
+		scanline[0][RED] = getc(fp);
+		scanline[0][GRN] = getc(fp);
+		scanline[0][BLU] = getc(fp);
+		scanline[0][EXP] = getc(fp);
+		if (feof(fp) || ferror(fp))
+			return(-1);
+		if (scanline[0][RED] == 1 &&
+				scanline[0][GRN] == 1 &&
+				scanline[0][BLU] == 1) {
+			for (i = scanline[0][EXP] << rshift; i > 0; i--) {
+				copycolr(scanline[0], scanline[-1]);
+				scanline++;
+				len--;
+			}
+			rshift += 8;
+		} else {
+			scanline++;
+			len--;
+			rshift = 0;
+		}
+	}
+	return(0);
+}
+
+
+int
 freadcolrs(scanline, len, fp)		/* read in an encoded colr scanline */
 register COLR  *scanline;
 int  len;
 register FILE  *fp;
 {
 	register int  i, j;
-	int  code;
+	int  code, val;
 					/* determine scanline type */
-	if (len < MINELEN)
+	if ((len < MINELEN) | (len > MAXELEN))
 		return(oldreadcolrs(scanline, len, fp));
 	if ((i = getc(fp)) == EOF)
 		return(-1);
@@ -123,53 +164,23 @@ register FILE  *fp;
 		if ((code = getc(fp)) == EOF)
 		    return(-1);
 		if (code > 128) {	/* run */
-		    scanline[j++][i] = getc(fp);
-		    for (code &= 127; --code; j++)
-			scanline[j][i] = scanline[j-1][i];
-		} else			/* non-run */
+		    code &= 127;
+		    if ((val = getc(fp)) == EOF)
+			return -1;
 		    while (code--)
-			scanline[j++][i] = getc(fp);
+			scanline[j++][i] = val;
+		} else			/* non-run */
+		    while (code--) {
+			if ((val = getc(fp)) == EOF)
+			    return -1;
+			scanline[j++][i] = val;
+		    }
 	    }
-	return(feof(fp) ? -1 : 0);
-}
-
-
-oldreadcolrs(scanline, len, fp)		/* read in an old colr scanline */
-register COLR  *scanline;
-int  len;
-register FILE  *fp;
-{
-	int  rshift;
-	register int  i;
-	
-	rshift = 0;
-	
-	while (len > 0) {
-		scanline[0][RED] = getc(fp);
-		scanline[0][GRN] = getc(fp);
-		scanline[0][BLU] = getc(fp);
-		scanline[0][EXP] = getc(fp);
-		if (feof(fp) || ferror(fp))
-			return(-1);
-		if (scanline[0][RED] == 1 &&
-				scanline[0][GRN] == 1 &&
-				scanline[0][BLU] == 1) {
-			for (i = scanline[0][EXP] << rshift; i > 0; i--) {
-				copycolr(scanline[0], scanline[-1]);
-				scanline++;
-				len--;
-			}
-			rshift += 8;
-		} else {
-			scanline++;
-			len--;
-			rshift = 0;
-		}
-	}
 	return(0);
 }
 
 
+int
 fwritescan(scanline, len, fp)		/* write out a scanline */
 register COLOR  *scanline;
 int  len;
@@ -195,6 +206,7 @@ FILE  *fp;
 }
 
 
+int
 freadscan(scanline, len, fp)		/* read in a scanline */
 register COLOR  *scanline;
 int  len;
@@ -222,11 +234,11 @@ FILE  *fp;
 }
 
 
+void
 setcolr(clr, r, g, b)		/* assign a short color value */
 register COLR  clr;
 double  r, g, b;
 {
-	double  frexp();
 	double  d;
 	int  e;
 	
@@ -239,15 +251,26 @@ double  r, g, b;
 		return;
 	}
 
-	d = frexp(d, &e) * 256.0 / d;
+	d = frexp(d, &e) * 255.9999 / d;
 
-	clr[RED] = r * d;
-	clr[GRN] = g * d;
-	clr[BLU] = b * d;
+	if (r > 0.0)
+		clr[RED] = r * d;
+	else
+		clr[RED] = 0;
+	if (g > 0.0)
+		clr[GRN] = g * d;
+	else
+		clr[GRN] = 0;
+	if (b > 0.0)
+		clr[BLU] = b * d;
+	else
+		clr[BLU] = 0;
+
 	clr[EXP] = e + COLXS;
 }
 
 
+void
 colr_color(col, clr)		/* convert short to float color */
 register COLOR  col;
 register COLR  clr;
@@ -265,6 +288,7 @@ register COLR  clr;
 }
 
 
+int
 bigdiff(c1, c2, md)			/* c1 delta c2 > md? */
 register COLOR  c1, c2;
 double  md;