--- ray/src/px/pinterp.c	1994/12/23 22:35:12	2.19
+++ ray/src/px/pinterp.c	1994/12/27 18:04:29	2.22
@@ -20,13 +20,17 @@ static char SCCSid[] = "$SunId$ LBL";
 
 #include "resolu.h"
 
+#define LOG2		0.69314718055994530942
+
 #define pscan(y)	(ourpict+(y)*hresolu)
 #define sscan(y)	(ourspict+(y)*hresolu)
 #define wscan(y)	(ourweigh+(y)*hresolu)
 #define zscan(y)	(ourzbuf+(y)*hresolu)
 #define averaging	(ourweigh != NULL)
+#define usematrix	(hasmatrix & !averaging)
+#define zisnorm		(!usematrix | ourview.type != VT_PER)
 
-#define MAXWT		100.		/* maximum pixel weight (averaging) */
+#define MAXWT		1000.		/* maximum pixel weight (averaging) */
 
 #define F_FORE		1		/* fill foreground */
 #define F_BACK		2		/* fill background */
@@ -52,8 +56,8 @@ double	pixaspect = 1.0;		/* pixel aspect ratio */
 double	zeps = .02;			/* allowed z epsilon */
 
 COLR	*ourpict;			/* output picture (COLR's) */
-COLOR	*ourspict;			/* output pixel sums (-a option) */
-float	*ourweigh = NULL;		/* output pixel weights (-a option) */
+COLOR	*ourspict;			/* output pixel sums (averaging) */
+float	*ourweigh = NULL;		/* output pixel weights (averaging) */
 float	*ourzbuf;			/* corresponding z-buffer */
 
 char	*progname;
@@ -65,8 +69,10 @@ int	(*fillfunc)() = backfill;	/* selected fill functio
 COLR	backcolr = BLKCOLR;		/* background color */
 COLOR	backcolor = BLKCOLOR;		/* background color (float) */
 double	backz = 0.0;			/* background z value */
-int	normdist = 1;			/* normalized distance? */
-double	ourexp = -1;			/* output picture exposure */
+int	normdist = 1;			/* i/o normalized distance? */
+double	ourexp = -1;			/* original picture exposure */
+int	expadj = 0;			/* exposure adjustment (f-stops) */
+double	rexpadj = 1;			/* real exposure adjustment */
 
 VIEW	theirview = STDVIEW;		/* input view */
 int	gotview;			/* got input view? */
@@ -95,6 +101,7 @@ char	*argv[];
 	int	gotvfile = 0;
 	int	doavg = -1;
 	char	*zfile = NULL;
+	char	*expcomp = NULL;
 	char	*err;
 	int	i, rval;
 
@@ -107,6 +114,10 @@ char	*argv[];
 			continue;
 		}
 		switch (argv[i][1]) {
+		case 'e':				/* exposure */
+			check(2,"f");
+			expcomp = argv[++i];
+			break;
 		case 't':				/* threshold */
 			check(2,"f");
 			zeps = atof(argv[++i]);
@@ -212,6 +223,23 @@ char	*argv[];
 		goto userr;
 	if (fillsamp == 1)
 		fillo &= ~F_BACK;
+	if (doavg < 0)
+		doavg = (argc-i) > 2;
+	if (expcomp != NULL)
+		if (expcomp[0] == '+' | expcomp[0] == '-') {
+			expadj = atof(expcomp) + (expcomp[0]=='+' ? .5 : -.5);
+			if (doavg)
+				rexpadj = pow(2.0, atof(expcomp));
+			else
+				rexpadj = pow(2.0, (double)expadj);
+		} else {
+			if (!isflt(expcomp))
+				goto userr;
+			rexpadj = atof(expcomp);
+			expadj = log(rexpadj)/LOG2 + (rexpadj>1 ? .5 : -.5);
+			if (!doavg)
+				rexpadj = pow(2.0, (double)expadj);
+		}
 						/* set view */
 	if ((err = setview(&ourview)) != NULL) {
 		fprintf(stderr, "%s: %s\n", progname, err);
@@ -219,8 +247,6 @@ char	*argv[];
 	}
 	normaspect(viewaspect(&ourview), &pixaspect, &hresolu, &vresolu);
 						/* allocate frame */
-	if (doavg < 0)
-		doavg = (argc-i) > 2;
 	if (doavg) {
 		ourspict = (COLOR *)bmalloc(hresolu*vresolu*sizeof(COLOR));
 		ourweigh = (float *)bmalloc(hresolu*vresolu*sizeof(float));
@@ -256,9 +282,13 @@ char	*argv[];
 		fprintview(&ourview, stdout);
 		putc('\n', stdout);
 	}
-	if (pixaspect < .99 || pixaspect > 1.01)
+	if (pixaspect < .99 | pixaspect > 1.01)
 		fputaspect(pixaspect, stdout);
-	if (ourexp > 0 && (ourexp < .995 || ourexp > 1.005))
+	if (ourexp > 0)
+		ourexp *= rexpadj;
+	else
+		ourexp = rexpadj;
+	if (ourexp < .995 | ourexp > 1.005)
 		fputexpos(ourexp, stdout);
 	fputformat(COLRFMT, stdout);
 	putc('\n', stdout);
@@ -271,7 +301,7 @@ char	*argv[];
 	exit(0);
 userr:
 	fprintf(stderr,
-	"Usage: %s [view opts][-t eps][-z zout][-fT][-n] pfile zspec ..\n",
+	"Usage: %s [view opts][-t eps][-z zout][-e spec][-a|-q][-fT][-n] pfile zspec ..\n",
 			progname);
 	exit(1);
 #undef check
@@ -490,7 +520,7 @@ double	z;
 		l1 = ABS(s1x);
 		if (p1isy = (ABS(s1y) > l1))
 			l1 = ABS(s1y);
-		if (l1 < 1)
+		else if (l1 < 1)
 			l1 = 1;
 	} else {
 		l1 = s1x = s1y = 1;
@@ -548,23 +578,21 @@ double	z;
 
 double
 movepixel(pos)				/* reposition image point */
-FVECT	pos;
+register FVECT	pos;
 {
-	double	d0, d1;
 	FVECT	pt, tdir, odir;
+	double	d;
 	register int	i;
 	
 	if (pos[2] <= 0)		/* empty pixel */
 		return(0);
-	if (normdist && theirview.type == VT_PER) {	/* adjust distance */
-		d0 = pos[0] + theirview.hoff - .5;
-		d1 = pos[1] + theirview.voff - .5;
-		pos[2] /= sqrt(1. + d0*d0*theirview.hn2 + d1*d1*theirview.vn2);
-	}
-	if (!averaging && hasmatrix) {
+	if (usematrix) {
 		pos[0] += theirview.hoff - .5;
 		pos[1] += theirview.voff - .5;
 		if (theirview.type == VT_PER) {
+			if (normdist)			/* adjust distance */
+				pos[2] /= sqrt(1. + pos[0]*pos[0]*theirview.hn2
+						+ pos[1]*pos[1]*theirview.vn2);
 			pos[0] *= pos[2];
 			pos[1] *= pos[2];
 		}
@@ -580,6 +608,9 @@ FVECT	pos;
 	} else {
 		if (viewray(pt, tdir, &theirview, pos[0], pos[1]) < -FTINY)
 			return(0);
+		if (!normdist & theirview.type == VT_PER)	/* adjust */
+			pos[2] *= sqrt(1. + pos[0]*pos[0]*theirview.hn2
+					+ pos[1]*pos[1]*theirview.vn2);
 		pt[0] += tdir[0]*pos[2];
 		pt[1] += tdir[1]*pos[2];
 		pt[2] += tdir[2]*pos[2];
@@ -596,12 +627,10 @@ FVECT	pos;
 	else
 		for (i = 0; i < 3; i++)
 			odir[i] = (pt[i] - ourview.vp[i])/pos[2];
-	d0 = DOT(odir,tdir);			/* compute pixel weight */
-	if (d0 <= FTINY)
-		return(0);		/* relative angle >= 90 degrees */
-	if (d0 >= 1.-1./MAXWT/MAXWT)
+	d = DOT(odir,tdir);			/* compute pixel weight */
+	if (d >= 1.-1./MAXWT/MAXWT)
 		return(MAXWT);		/* clip to maximum weight */
-	return(1./sqrt(1.-d0));
+	return(1./sqrt(1.-d));
 }
 
 
@@ -682,6 +711,7 @@ int	zfd;
 	}
 	if (yl->max >= numscans(&tresolu))
 		yl->max = numscans(&tresolu) - 1;
+	y -= step;
 	for (x = numscans(&tresolu) - 1; x > y; x--)	/* fill bottom rows */
 		copystruct(xl+x, xl+y);
 	return(yl->max >= yl->min);
@@ -811,6 +841,7 @@ int	(*fill)();
 clipaft()			/* perform aft clipping as indicated */
 {
 	register int	x, y;
+	int	adjtest = ourview.type == VT_PER & zisnorm;
 	double	tstdist;
 	double	yzn2, vx;
 
@@ -818,14 +849,14 @@ clipaft()			/* perform aft clipping as indicated */
 		return;
 	tstdist = ourview.vaft - ourview.vfore;
 	for (y = 0; y < vresolu; y++) {
-		if (ourview.type == VT_PER) {		/* adjust distance */
+		if (adjtest) {				/* adjust test */
 			yzn2 = (y+.5)/vresolu + ourview.voff - .5;
 			yzn2 = 1. + yzn2*yzn2*ourview.vn2;
 			tstdist = (ourview.vaft - ourview.vfore)*sqrt(yzn2);
 		}
 		for (x = 0; x < hresolu; x++)
 			if (zscan(y)[x] > tstdist) {
-				if (ourview.type == VT_PER) {
+				if (adjtest) {
 					vx = (x+.5)/hresolu + ourview.hoff - .5;
 					if (zscan(y)[x] <= (ourview.vaft -
 							ourview.vfore) *
@@ -842,7 +873,7 @@ clipaft()			/* perform aft clipping as indicated */
 }
 
 
-writepicture()				/* write out picture */
+writepicture()				/* write out picture (alters buffer) */
 {
 	int	y;
 	register int	x;
@@ -852,48 +883,49 @@ writepicture()				/* write out picture */
 	for (y = vresolu-1; y >= 0; y--)
 		if (averaging) {
 			for (x = 0; x < hresolu; x++) {	/* average pixels */
-				d = 1./wscan(y)[x];
+				d = rexpadj/wscan(y)[x];
 				scalecolor(sscan(y)[x], d);
 			}
 			if (fwritescan(sscan(y), hresolu, stdout) < 0)
 				syserror(progname);
-		} else if (fwritecolrs(pscan(y), hresolu, stdout) < 0)
-			syserror(progname);
+		} else {
+			if (expadj)
+				shiftcolrs(pscan(y), hresolu, expadj);
+			if (fwritecolrs(pscan(y), hresolu, stdout) < 0)
+				syserror(progname);
+		}
 }
 
 
-writedistance(fname)			/* write out z file */
+writedistance(fname)			/* write out z file (alters buffer) */
 char	*fname;
 {
-	int	donorm = normdist && ourview.type == VT_PER;
+	int	donorm = normdist & !zisnorm ? 1 :
+			ourview.type == VT_PER & !normdist & zisnorm ? -1 : 0;
 	int	fd;
 	int	y;
-	float	*zout;
 
 	if ((fd = open(fname, O_WRONLY|O_CREAT|O_TRUNC, 0666)) == -1)
 		syserror(fname);
-	if (donorm
-	&& (zout = (float *)malloc(hresolu*sizeof(float))) == NULL)
-		syserror(progname);
 	for (y = vresolu-1; y >= 0; y--) {
 		if (donorm) {
-			double	vx, yzn2;
+			double	vx, yzn2, d;
 			register int	x;
 			yzn2 = (y+.5)/vresolu + ourview.voff - .5;
 			yzn2 = 1. + yzn2*yzn2*ourview.vn2;
 			for (x = 0; x < hresolu; x++) {
 				vx = (x+.5)/hresolu + ourview.hoff - .5;
-				zout[x] = zscan(y)[x]
-					* sqrt(vx*vx*ourview.hn2 + yzn2);
+				d = sqrt(vx*vx*ourview.hn2 + yzn2);
+				if (donorm > 0)
+					zscan(y)[x] *= d;
+				else
+					zscan(y)[x] /= d;
 			}
-		} else
-			zout = zscan(y);
-		if (write(fd, (char *)zout, hresolu*sizeof(float))
+		}
+		if (write(fd, (char *)zscan(y), hresolu*sizeof(float))
 				< hresolu*sizeof(float))
 			syserror(fname);
 	}
-	if (donorm)
-		free((char *)zout);
 	close(fd);
 }
 
@@ -978,6 +1010,7 @@ clearqueue()				/* process queue */
 	float	fbuf[6*(PACKSIZ+1)];
 	register float	*fbp;
 	register int	i;
+	double	vx, vy;
 
 	if (queuesiz == 0)
 		return;
@@ -1012,7 +1045,14 @@ clearqueue()				/* process queue */
 		} else
 			setcolr(pscan(queue[i][1])[queue[i][0]],
 					fbp[0], fbp[1], fbp[2]);
-		zscan(queue[i][1])[queue[i][0]] = fbp[3];
+		if (zisnorm)
+			zscan(queue[i][1])[queue[i][0]] = fbp[3];
+		else {
+			vx = (queue[i][0]+.5)/hresolu + ourview.hoff - .5;
+			vy = (queue[i][1]+.5)/vresolu + ourview.voff - .5;
+			zscan(queue[i][1])[queue[i][0]] = fbp[3] / sqrt(1. +
+					vx*vx*ourview.hn2 + vy*vy*ourview.vn2);
+		}
 		fbp += 4;
 	}
 	queuesiz = 0;