--- ray/src/px/x11image.c	1991/05/03 10:54:47	1.20
+++ ray/src/px/x11image.c	1991/08/26 10:15:01	1.25
@@ -1,4 +1,4 @@
-/* Copyright (c) 1990 Regents of the University of California */
+/* Copyright (c) 1991 Regents of the University of California */
 
 #ifndef lint
 static char SCCSid[] = "$SunId$ LBL";
@@ -248,6 +248,7 @@ init()			/* get data and open window */
 	XSetFunction(thedisplay, revgc, GXinvert);
 	XDefineCursor(thedisplay, wind, XCreateFontCursor(thedisplay, 
 			XC_diamond_cross));
+	XStoreName(thedisplay, wind, fname == NULL ? progname : fname);
 	if (geometry != NULL) {
 		bzero((char *)&oursizhints, sizeof(oursizhints));
 		i = XParseGeometry(geometry, &oursizhints.x, &oursizhints.y,
@@ -280,8 +281,6 @@ init()			/* get data and open window */
 			|ButtonMotionMask|StructureNotifyMask
 			|KeyPressMask|ExposureMask);
 	XMapWindow(thedisplay, wind);
-				/* store name last as ready signal */
-	XStoreName(thedisplay, wind, fname == NULL ? progname : fname);
 	return;
 memerr:
 	quiterr("out of memory");
@@ -581,6 +580,8 @@ int  x0, y0, x1, y1;
 avgbox(clr)				/* average color over current box */
 COLOR  clr;
 {
+	static COLOR  lc;
+	static int  ll, lr, lt, lb;
 	int  left, right, top, bottom;
 	int  y;
 	double  d;
@@ -604,6 +605,10 @@ COLOR  clr;
 		bottom = ymax;
 	if (top >= bottom)
 		return(-1);
+	if (left == ll && right == lr && top == lt && bottom == lb) {
+		copycolor(clr, lc);
+		return;
+	}
 	for (y = top; y < bottom; y++) {
 		if (getscan(y) == -1)
 			return(-1);
@@ -614,6 +619,8 @@ COLOR  clr;
 	}
 	d = 1.0/((right-left)*(bottom-top));
 	scalecolor(clr, d);
+	ll = left; lr = right; lt = top; lb = bottom;
+	copycolor(lc, clr);
 	return(0);
 }
 
@@ -622,7 +629,7 @@ getmono()			/* get monochrome data */
 {
 	register unsigned char	*dp;
 	register int	x, err;
-	int	y;
+	int	y, errp;
 	short	*cerr;
 
 	if ((cerr = (short *)calloc(xmax,sizeof(short))) == NULL)
@@ -637,12 +644,14 @@ getmono()			/* get monochrome data */
 		for (x = 0; x < xmax; x++) {
 			if (!(x&7))
 				*++dp = 0;
+			errp = err;
 			err += normbright(scanline[x]) + cerr[x];
 			if (err > 127)
 				err -= 255;
 			else
 				*dp |= 1<<(7-(x&07));
-			cerr[x] = err >>= 1;
+			err /= 3;
+			cerr[x] = err + errp;
 		}
 	}
 	free((char *)cerr);
@@ -658,6 +667,7 @@ COLR  *scan;
 	static char  *dp;
 	register int  err;
 	register int	x, ti;
+	int  errp;
 
 	if (iconheight == 0) {		/* initialize */
 		if (xmax <= ICONSIZ && ymax <= ICONSIZ) {
@@ -666,8 +676,12 @@ COLR  *scan;
 		} else if (xmax > ymax) {
 			iconwidth = ICONSIZ;
 			iconheight = ICONSIZ*ymax/xmax;
+			if (iconheight < 1)
+				iconheight = 1;
 		} else {
 			iconwidth = ICONSIZ*xmax/ymax;
+			if (iconwidth < 1)
+				iconwidth = 1;
 			iconheight = ICONSIZ;
 		}
 		ynext = 0;
@@ -679,13 +693,15 @@ COLR  *scan;
 	for (x = 0; x < iconwidth; x++) {
 		if (!(x&7))
 			*++dp = 0;
+		errp = err;
 		ti = x*xmax/iconwidth;
 		err += normbright(scan[ti]) + cerr[x];
 		if (err > 127)
 			err -= 255;
 		else
 			*dp |= 1<<(x&07);
-		cerr[x] = err >>= 1;
+		err /= 3;
+		cerr[x] = err + errp;
 	}
 	ynext++;
 }