--- ray/src/px/pcomb.c	1995/10/16 12:04:33	2.16
+++ ray/src/px/pcomb.c	1998/10/27 09:08:25	2.21
@@ -29,6 +29,7 @@ struct {
 	FILE	*fp;		/* stream pointer */
 	VIEW	vw;		/* view for picture */
 	RESOLU	rs;		/* image resolution and orientation */
+	float	pa;		/* pixel aspect ratio */
 	COLOR	*scan[WINSIZ];	/* input scanline window */
 	COLOR	coef;		/* coefficient */
 	COLOR	expos;		/* recorded exposure */
@@ -45,10 +46,14 @@ char	vbrtin[] = "li";
 char	vbrtout[] = "lo";
 char	vcolexp[3][4] = {"re", "ge", "be"};
 char	vbrtexp[] = "le";
+char	vpixaspect[] = "pa";
 
-char	vray[6][4] = {"Ox", "Oy", "Oz", "Dx", "Dy", "Dz"};
+char	vray[7][4] = {"Ox", "Oy", "Oz", "Dx", "Dy", "Dz", "T"};
 
+char	vpsize[] = "S";
+
 char	vnfiles[] = "nfiles";
+char	vwhteff[] = "WE";
 char	vxmax[] = "xmax";
 char	vymax[] = "ymax";
 char	vxres[] = "xres";
@@ -114,6 +119,7 @@ char	*argv[];
 		setcolor(input[nfiles].coef, 1.0, 1.0, 1.0);
 		setcolor(input[nfiles].expos, 1.0, 1.0, 1.0);
 		copystruct(&input[nfiles].vw, &stdview);
+		input[nfiles].pa = 1.0;
 	}
 	nfiles = 0;
 	original = 0;
@@ -229,14 +235,14 @@ char	*s;
 	COLOR	ctmp;
 
 	if (isheadid(s))			/* header id */
-		return;		/* don't echo */
+		return(0);	/* don't echo */
 	if (formatval(fmt, s)) {		/* check format */
 		if (globmatch(ourfmt, fmt)) {
 			wrongformat = 0;
 			strcpy(ourfmt, fmt);
 		} else
 			wrongformat = 1;
-		return;		/* don't echo */
+		return(0);	/* don't echo */
 	}
 	if (isexpos(s)) {			/* exposure */
 		d = exposval(s);
@@ -244,11 +250,13 @@ char	*s;
 	} else if (iscolcor(s)) {		/* color correction */
 		colcorval(ctmp, s);
 		multcolor(input[nfiles].expos, ctmp);
-	} else if (isview(s) && sscanview(&input[nfiles].vw, s) > 0)
+	} else if (isaspect(s))
+		input[nfiles].pa *= aspectval(s);
+	else if (isview(s) && sscanview(&input[nfiles].vw, s) > 0)
 		gotview++;
 						/* echo line */
 	putchar('\t');
-	fputs(s, stdout);
+	return(fputs(s, stdout));
 }
 
 
@@ -308,9 +316,10 @@ double	(*ourbright)() = rgb_bright;
 
 init()					/* perform final setup */
 {
-	double	l_colin(), l_expos(), l_ray();
+	double	l_colin(), l_expos(), l_pixaspect(), l_ray(), l_psize();
 	register int	i;
 						/* define constants */
+	varset("PI", ':', PI);
 	varset(vnfiles, ':', (double)nfiles);
 	varset(vxmax, ':', (double)xmax);
 	varset(vymax, ':', (double)ymax);
@@ -321,11 +330,16 @@ init()					/* perform final setup */
 	}
 	funset(vbrtexp, 1, ':', l_expos);
 	funset(vbrtin, 1, '=', l_colin);
-	for (i = 0; i < 6; i++)
+	funset(vpixaspect, 1, ':', l_pixaspect);
+	for (i = 0; i < 7; i++)
 		funset(vray[i], 1, '=', l_ray);
+	funset(vpsize, 1, '=', l_psize);
 						/* set brightness function */
-	if (!strcmp(ourfmt, CIEFMT))
+	if (!strcmp(ourfmt, CIEFMT)) {
+		varset(vwhteff, ':', 1.0);
 		ourbright = xyz_bright;
+	} else
+		varset(vwhteff, ':', WHTEFFICACY);
 }
 
 
@@ -436,6 +450,18 @@ register char	*nam;
 
 
 double
+l_pixaspect()			/* return pixel aspect ratio */
+{
+	register int	fn;
+
+	fn = argument(1) - .5;
+	if (fn < 0 || fn >= nfiles)
+		return(1.0);
+	return(input[fn].pa);
+}
+
+
+double
 l_colin(nam)			/* return color value for picture */
 register char	*nam;
 {
@@ -443,10 +469,7 @@ register char	*nam;
 	register int	n, xoff, yoff;
 	double	d;
 
-	d = argument(1);
-	if (d > -.5 && d < .5)
-		return((double)nfiles);
-	fn = d - .5;
+	fn = argument(1) - .5;
 	if (fn < 0 || fn >= nfiles) {
 		errno = EDOM;
 		return(0.0);
@@ -498,15 +521,12 @@ register char	*nam;
 {
 	static unsigned long	ltick[MAXINP];
 	static FVECT	lorg[MAXINP], ldir[MAXINP];
+	static double	ldist[MAXINP];
 	FLOAT	loc[2];
-	double	d;
 	int	fn;
 	register int	i;
 
-	d = argument(1);
-	if (d > -.5 && d < .5)
-		return((double)nfiles);
-	fn = d - .5;
+	fn = argument(1) - .5;
 	if (fn < 0 || fn >= nfiles) {
 		errno = EDOM;
 		return(0.0);
@@ -514,22 +534,69 @@ register char	*nam;
 	if (ltick[fn] < eclock) {		/* need to compute? */
 		lorg[fn][0] = lorg[fn][1] = lorg[fn][2] = 0.0;
 		ldir[fn][0] = ldir[fn][1] = ldir[fn][2] = 0.0;
+		ldist[fn] = -1.0;
 		if (input[fn].vw.type == 0)
 			errno = EDOM;
 		else {
 			pix2loc(loc, &input[fn].rs, xscan, ymax-1-yscan);
-			if (viewray(lorg[fn], ldir[fn],
-					&input[fn].vw, loc[0], loc[1]) < 0)
-				errno = ERANGE;
+			ldist[fn] = viewray(lorg[fn], ldir[fn],
+					&input[fn].vw, loc[0], loc[1]);
 		}
 		ltick[fn] = eclock;
 	}
-	i = 6;
+	if (nam == vray[i=6])
+		return(ldist[fn]);
 	while (i--)
 		if (nam == vray[i])
 			return(i < 3 ? lorg[fn][i] : ldir[fn][i-3]);
 	eputs("Bad call to l_ray()!\n");
 	quit(1);
+}
+
+
+double
+l_psize()			/* compute pixel size in steradians */
+{
+	static unsigned long	ltick[MAXINP];
+	static double	psize[MAXINP];
+	FVECT	dir0, org, dirx, diry;
+	FLOAT	locx[2], locy[2];
+	double	d;
+	int	fn;
+	register int	i;
+
+	d = argument(1);
+	if (d < .5 || d >= nfiles+.5) {
+		errno = EDOM;
+		return(0.0);
+	}
+	fn = d - .5;
+	if (ltick[fn] < eclock) {		/* need to compute? */
+		psize[fn] = 0.0;
+		if (input[fn].vw.type == 0)
+			errno = EDOM;
+		else if (input[fn].vw.type != VT_PAR &&
+				funvalue(vray[6], 1, &d) >= 0) {
+			for (i = 0; i < 3; i++)
+				dir0[i] = funvalue(vray[3+i], 1, &d);
+			pix2loc(locx, &input[fn].rs, xscan+1, ymax-1-yscan);
+			pix2loc(locy, &input[fn].rs, xscan, ymax-yscan);
+			if (viewray(org, dirx, &input[fn].vw,
+					locx[0], locx[1]) >= 0 &&
+					viewray(org, diry, &input[fn].vw,
+					locy[0], locy[1]) >= 0) {
+						/* approximate solid angle */
+				for (i = 0; i < 3; i++) {
+					dirx[i] -= dir0[i];
+					diry[i] -= dir0[i];
+				}
+				fcross(dir0, dirx, diry);
+				psize[fn] = 0.5 * sqrt(DOT(dir0,dir0));
+			}
+		}
+		ltick[fn] = eclock;
+	}
+	return(psize[fn]);
 }