--- ray/src/rt/rpict.c	1991/04/09 09:31:01	1.24
+++ ray/src/rt/rpict.c	1991/08/13 12:16:34	1.31
@@ -24,6 +24,10 @@ static char SCCSid[] = "$SunId$ LBL";
 
 #include  "random.h"
 
+int  dimlist[MAXDIM];			/* sampling dimensions */
+int  ndims = 0;				/* number of sampling dimensions */
+int  samplendx;				/* sample index number */
+
 VIEW  ourview = STDVIEW;		/* view parameters */
 int  hresolu = 512;			/* horizontal resolution */
 int  vresolu = 512;			/* vertical resolution */
@@ -36,6 +40,9 @@ double  dstrpix = 0.67;			/* square pixel distribution
 double  dstrsrc = 0.0;			/* square source distribution */
 double  shadthresh = .05;		/* shadow threshold */
 double  shadcert = .5;			/* shadow certainty */
+int  directrelay = 0;			/* number of source relays */
+int  vspretest = 512;			/* virtual source pretest density */
+int  directinvis = 0;			/* sources invisible? */
 
 int  maxdepth = 6;			/* maximum recursion depth */
 double  minweight = 5e-3;		/* minimum ray weight */
@@ -60,7 +67,7 @@ extern long  tstart;			/* starting time */
 
 extern long  nrays;			/* number of rays traced */
 
-#define  MAXDIV		32		/* maximum sample size */
+#define  MAXDIV		15		/* maximum sample size */
 
 #define  pixjitter()	(.5+dstrpix*(.5-frandom()))
 
@@ -122,8 +129,12 @@ char  *zfile, *oldfile;
 					/* check sampling */
 	if (psample < 1)
 		psample = 1;
-	else if (psample > MAXDIV)
+	else if (psample > MAXDIV) {
+		sprintf(errmsg, "pixel sampling reduced from %d to %d",
+				psample, MAXDIV);
+		error(WARNING, errmsg);
 		psample = MAXDIV;
+	}
 					/* allocate scanlines */
 	for (i = 0; i <= psample; i++) {
 		scanbar[i] = (COLOR *)malloc(hresolu*sizeof(COLOR));
@@ -333,7 +344,7 @@ pixvalue(col, x, y)		/* compute pixel value */
 COLOR  col;			/* returned color */
 int  x, y;			/* pixel position */
 {
-	static RAY  thisray;	/* our ray for this pixel */
+	static RAY  thisray;
 
 	if (viewray(thisray.rorg, thisray.rdir, &ourview,
 			(x+pixjitter())/hresolu, (y+pixjitter())/vresolu) < 0) {
@@ -342,7 +353,9 @@ int  x, y;			/* pixel position */
 	}
 
 	rayorigin(&thisray, NULL, PRIMARY, 1.0);
-	
+
+	samplendx = pixnumber(x,y,hresolu,vresolu);	/* set pixel index */
+
 	rayvalue(&thisray);			/* trace ray */
 
 	copycolor(col, thisray.rcol);		/* return color */
@@ -400,4 +413,16 @@ char  *oldfile;
 	return(y);
 writerr:
 	error(SYSTEM, "write error in salvage");
+}
+
+
+int
+pixnumber(x, y, xres, yres)		/* compute pixel index (brushed) */
+register int  x, y;
+int  xres, yres;
+{
+	x -= y;
+	while (x < 0)
+		x += xres;
+	return((((x>>2)*yres + y) << 2) + (x & 3));
 }