--- ray/src/px/ximage.c	1990/03/12 15:14:49	1.24
+++ ray/src/px/ximage.c	1990/11/07 13:10:39	1.27
@@ -287,7 +287,7 @@ getras()				/* get raster file */
 	}
 	return;
 memerr:
-	quit("out of memory");
+	quiterr("out of memory");
 }
 
 
@@ -407,8 +407,9 @@ XKeyEvent  *ekey;
 			XFeep(0);
 			return(-1);
 		}
-		viewray(rorg, rdir, &ourview, (ekey->x-xoff+.5)/xmax,
-				(ymax-1-ekey->y+yoff+.5)/ymax);
+		if (viewray(rorg, rdir, &ourview, (ekey->x-xoff+.5)/xmax,
+				(ymax-1-ekey->y+yoff+.5)/ymax) < 0)
+			return(-1);
 		printf("%e %e %e ", rorg[0], rorg[1], rorg[2]);
 		printf("%e %e %e\n", rdir[0], rdir[1], rdir[2]);
 		fflush(stdout);
@@ -547,7 +548,7 @@ getmono()			/* get monochrome data */
 
 	if ((inl = (rgbpixel *)malloc(xmax*sizeof(rgbpixel))) == NULL
 			|| (cerr = (short *)calloc(xmax,sizeof(short))) == NULL)
-		quit("out of memory in getmono");
+		quiterr("out of memory in getmono");
 	dp = ourras->data.m - 1;
 	for (y = 0; y < ymax; y++) {
 		picreadline3(y, inl);
@@ -634,7 +635,7 @@ int  y;
 		if (scanpos == NULL || scanpos[y] == -1)
 			return(-1);
 		if (fseek(fin, scanpos[y], 0) == -1)
-			quit("fseek error");
+			quiterr("fseek error");
 		cury = y;
 	} else if (scanpos != NULL)
 		scanpos[y] = ftell(fin);
@@ -680,7 +681,7 @@ colormap  map;
 	register int  i, val;
 
 	for (i = 0; i < 256; i++) {
-		val = pow(i/256.0, 1.0/gamcor) * 256.0;
+		val = pow((i+0.5)/256.0, 1.0/gamcor) * 256.0;
 		map[0][i] = map[1][i] = map[2][i] = val;
 	}
 }