--- ray/src/rt/rv2.c	1991/11/11 17:42:19	1.33
+++ ray/src/rt/rv2.c	2013/10/18 17:04:13	2.64
@@ -1,36 +1,47 @@
-/* Copyright (c) 1991 Regents of the University of California */
-
 #ifndef lint
-static char SCCSid[] = "$SunId$ LBL";
+static const char	RCSid[] = "$Id: rv2.c,v 2.64 2013/10/18 17:04:13 greg Exp $";
 #endif
-
 /*
  *  rv2.c - command routines used in tracing a view.
  *
- *     3/24/87
+ *  External symbols declared in rpaint.h
  */
 
-#include  "ray.h"
+#include "copyright.h"
 
-#include  "octree.h"
+#include  <ctype.h>
+#include  <string.h>
 
+#include  "platform.h"
+#include  "rtprocess.h"	/* win_popen() */
+#include  "paths.h"
+#include  "ray.h"
+#include  "source.h"
+#include  "ambient.h"
 #include  "otypes.h"
-
 #include  "rpaint.h"
 
-#include  "resolu.h"
+extern int  psample;			/* pixel sample size */
+extern double  maxdiff;			/* max. sample difference */
 
-#include  <ctype.h>
+#define  CTRL(c)	((c)-'@')
 
-#define  CTRL(c)	('c'-'@')
+#ifdef  SMLFLT
+#define  sscanvec(s,v)	(sscanf(s,"%f %f %f",v,v+1,v+2)==3)
+#else
+#define  sscanvec(s,v)	(sscanf(s,"%lf %lf %lf",v,v+1,v+2)==3)
+#endif
 
-extern char  VersionID[];
+extern char  rifname[128];		/* rad input file name */
+
 extern char  *progname;
 extern char  *octname;
 
 
-getframe(s)				/* get a new frame */
-char  *s;
+void
+getframe(				/* get a new frame */
+	char  *s
+)
 {
 	if (getrect(s, &pframe) < 0)
 		return;
@@ -38,27 +49,40 @@ char  *s;
 }
 
 
-getrepaint(s)				/* get area and repaint */
-char  *s;
+void
+getrepaint(				/* get area and repaint */
+	char  *s
+)
 {
 	RECT  box;
 
 	if (getrect(s, &box) < 0)
 		return;
-	paintrect(&ptrunk, 0, 0, hresolu, vresolu, &box);
+	paintrect(&ptrunk, &box);
 }
 
 
-getview(s)				/* get/show view parameters */
-char  *s;
+void
+getview(				/* get/show/save view parameters */
+	char  *s
+)
 {
 	FILE  *fp;
 	char  buf[128];
 	char  *fname;
 	int  change = 0;
-	VIEW  nv;
+	VIEW  nv = ourview;
 
-	if (sscanf(s, "%s", buf) == 1) {	/* write parameters to a file */
+	while (isspace(*s))
+		s++;
+	if (*s == '-') {			/* command line parameters */
+		if (sscanview(&nv, s))
+			newview(&nv);
+		else
+			error(COMMAND, "bad view option(s)");
+		return;
+	}
+	if (nextword(buf, sizeof(buf), s) != NULL) {	/* write to a file */
 		if ((fname = getpath(buf, NULL, 0)) == NULL ||
 				(fp = fopen(fname, "a")) == NULL) {
 			sprintf(errmsg, "cannot open \"%s\"", buf);
@@ -68,82 +92,82 @@ char  *s;
 		fputs(progname, fp);
 		fprintview(&ourview, fp);
 		fputs(sskip(s), fp);
-		fputs("\n", fp);
+		putc('\n', fp);
 		fclose(fp);
 		return;
 	}
 	sprintf(buf, "view type (%c): ", ourview.type);
 	(*dev->comout)(buf);
 	(*dev->comin)(buf, NULL);
-	if (buf[0] == CTRL(C)) return;
+	if (buf[0] == CTRL('C')) return;
 	if (buf[0] && buf[0] != ourview.type) {
 		nv.type = buf[0];
 		change++;
-	} else
-		nv.type = ourview.type;
+	}
 	sprintf(buf, "view point (%.6g %.6g %.6g): ",
 			ourview.vp[0], ourview.vp[1], ourview.vp[2]);
 	(*dev->comout)(buf);
 	(*dev->comin)(buf, NULL);
-	if (buf[0] == CTRL(C)) return;
-	if (sscanf(buf, "%lf %lf %lf", &nv.vp[0], &nv.vp[1], &nv.vp[2]) == 3)
+	if (buf[0] == CTRL('C')) return;
+	if (sscanvec(buf, nv.vp))
 		change++;
-	else
-		VCOPY(nv.vp, ourview.vp);
 	sprintf(buf, "view direction (%.6g %.6g %.6g): ",
-			ourview.vdir[0], ourview.vdir[1], ourview.vdir[2]);
+			ourview.vdir[0]*ourview.vdist,
+			ourview.vdir[1]*ourview.vdist,
+			ourview.vdir[2]*ourview.vdist);
 	(*dev->comout)(buf);
 	(*dev->comin)(buf, NULL);
-	if (buf[0] == CTRL(C)) return;
-	if (sscanf(buf,"%lf %lf %lf",&nv.vdir[0],&nv.vdir[1],&nv.vdir[2]) == 3)
+	if (buf[0] == CTRL('C')) return;
+	if (sscanvec(buf, nv.vdir)) {
+		nv.vdist = 1.;
 		change++;
-	else
-		VCOPY(nv.vdir, ourview.vdir);
+	}
 	sprintf(buf, "view up (%.6g %.6g %.6g): ",
 			ourview.vup[0], ourview.vup[1], ourview.vup[2]);
 	(*dev->comout)(buf);
 	(*dev->comin)(buf, NULL);
-	if (buf[0] == CTRL(C)) return;
-	if (sscanf(buf,"%lf %lf %lf",&nv.vup[0],&nv.vup[1],&nv.vup[2]) == 3)
+	if (buf[0] == CTRL('C')) return;
+	if (sscanvec(buf, nv.vup))
 		change++;
-	else
-		VCOPY(nv.vup, ourview.vup);
 	sprintf(buf, "view horiz and vert size (%.6g %.6g): ",
 			ourview.horiz, ourview.vert);
 	(*dev->comout)(buf);
 	(*dev->comin)(buf, NULL);
-	if (buf[0] == CTRL(C)) return;
+	if (buf[0] == CTRL('C')) return;
 	if (sscanf(buf, "%lf %lf", &nv.horiz, &nv.vert) == 2)
 		change++;
-	else {
-		nv.horiz = ourview.horiz; nv.vert = ourview.vert;
-	}
+	sprintf(buf, "fore and aft clipping plane (%.6g %.6g): ",
+			ourview.vfore, ourview.vaft);
+	(*dev->comout)(buf);
+	(*dev->comin)(buf, NULL);
+	if (buf[0] == CTRL('C')) return;
+	if (sscanf(buf, "%lf %lf", &nv.vfore, &nv.vaft) == 2)
+		change++;
 	sprintf(buf, "view shift and lift (%.6g %.6g): ",
 			ourview.hoff, ourview.voff);
 	(*dev->comout)(buf);
 	(*dev->comin)(buf, NULL);
-	if (buf[0] == CTRL(C)) return;
+	if (buf[0] == CTRL('C')) return;
 	if (sscanf(buf, "%lf %lf", &nv.hoff, &nv.voff) == 2)
 		change++;
-	else {
-		nv.hoff = ourview.hoff; nv.voff = ourview.voff;
-	}
 	if (change)
 		newview(&nv);
 }
 
 
-lastview(s)				/* return to a previous view */
-char  *s;
+void
+lastview(				/* return to a previous view */
+	char  *s
+)
 {
 	char  buf[128];
 	char  *fname;
 	int  success;
 	VIEW  nv;
-
-	if (sscanf(s, "%s", buf) == 1) {	/* get parameters from a file */
-		copystruct(&nv, &stdview);
-		if ((fname = getpath(buf, NULL, 0)) == NULL ||
+					/* get parameters from a file */
+	if (nextword(buf, sizeof(buf), s) != NULL) {
+		nv = stdview;
+		if ((fname = getpath(buf, "", R_OK)) == NULL ||
 				(success = viewfile(fname, &nv, NULL)) == -1) {
 			sprintf(errmsg, "cannot open \"%s\"", buf);
 			error(COMMAND, errmsg);
@@ -159,35 +183,145 @@ char  *s;
 		error(COMMAND, "no previous view");
 		return;
 	}
-	copystruct(&nv, &ourview);
-	copystruct(&ourview, &oldview);
-	copystruct(&oldview, &nv);
-	newimage();
+	nv = ourview;
+	ourview = oldview;
+	oldview = nv;
+	newimage(NULL);
 }
 
 
-getaim(s)				/* aim camera */
-char  *s;
+void
+saveview(				/* save view to rad file */
+	char  *s
+)
 {
-	extern double  tan(), atan();
-	double  zfact;
+	char  view[64];
+	char  *fname;
+	FILE  *fp;
+
+	if (*atos(view, sizeof(view), s)) {
+		if (isint(view)) {
+			error(COMMAND, "cannot write view by number");
+			return;
+		}
+		s = sskip(s);
+	}
+	if (nextword(rifname, sizeof(rifname), s) == NULL && !rifname[0]) {
+		error(COMMAND, "no previous rad file");
+		return;
+	}
+	if ((fname = getpath(rifname, NULL, 0)) == NULL ||
+			(fp = fopen(fname, "a")) == NULL) {
+		sprintf(errmsg, "cannot open \"%s\"", rifname);
+		error(COMMAND, errmsg);
+		return;
+	}
+	fputs("view= ", fp);
+	fputs(view, fp);
+	fprintview(&ourview, fp);
+	putc('\n', fp);
+	fclose(fp);
+}
+
+
+void
+loadview(				/* load view from rad file */
+	char  *s
+)
+{
+	char  buf[512];
+	char  *fname;
+	FILE  *fp;
 	VIEW  nv;
 
+	strcpy(buf, "rad -n -s -V -v ");
+	if (sscanf(s, "%s", buf+strlen(buf)) == 1)
+		s = sskip(s);
+	else
+		strcat(buf, "1");
+	if (nextword(rifname, sizeof(rifname), s) == NULL && !rifname[0]) {
+		error(COMMAND, "no previous rad file");
+		return;
+	}
+	if ((fname = getpath(rifname, "", R_OK)) == NULL) {
+		sprintf(errmsg, "cannot access \"%s\"", rifname);
+		error(COMMAND, errmsg);
+		return;
+	}
+	sprintf(buf+strlen(buf), " %s", fname);
+	if ((fp = popen(buf, "r")) == NULL) {
+		error(COMMAND, "cannot run rad");
+		return;
+	}
+	buf[0] = '\0';
+	fgets(buf, sizeof(buf), fp);
+	pclose(fp);
+	nv = stdview;
+	if (!sscanview(&nv, buf)) {
+		error(COMMAND, "rad error -- no such view?");
+		return;
+	}
+	newview(&nv);
+}
+
+
+void
+getaim(				/* aim camera */
+	char  *s
+)
+{
+	VIEW  nv = ourview;
+	double  zfact;
+
 	if (getinterest(s, 1, nv.vdir, &zfact) < 0)
 		return;
-	nv.type = ourview.type;
-	VCOPY(nv.vp, ourview.vp);
-	VCOPY(nv.vup, ourview.vup);
-	nv.hoff = ourview.hoff; nv.voff = ourview.voff;
-	nv.horiz = ourview.horiz; nv.vert = ourview.vert;
 	zoomview(&nv, zfact);
 	newview(&nv);
 }
 
 
-getmove(s)				/* move camera */
-char  *s;
+void
+getfocus(				/* set focus distance */
+	char *s
+)
 {
+	char  buf[64];
+	double	dist;
+
+	if (sscanf(s, "%lf", &dist) < 1) {
+		int	x, y;
+		RAY	thisray;
+		if (dev->getcur == NULL)
+			return;
+		(*dev->comout)("Pick focus point\n");
+		if ((*dev->getcur)(&x, &y) == ABORT)
+			return;
+		if ((thisray.rmax = viewray(thisray.rorg, thisray.rdir,
+			&ourview, (x+.5)/hresolu, (y+.5)/vresolu)) < -FTINY) {
+			error(COMMAND, "not on image");
+			return;
+		}
+		rayorigin(&thisray, PRIMARY, NULL, NULL);
+		if (!localhit(&thisray, &thescene)) {
+			error(COMMAND, "not a local object");
+			return;
+		}
+		dist = thisray.rot;
+	} else if (dist <= .0) {
+		error(COMMAND, "focus distance must be positive");
+		return;
+	}
+	ourview.vdist = dist;
+	sprintf(buf, "Focus distance set to %f\n", dist);
+	(*dev->comout)(buf);
+}
+
+
+void
+getmove(				/* move camera */
+	char  *s
+)
+{
 	FVECT  vc;
 	double  mag;
 
@@ -197,12 +331,12 @@ char  *s;
 }
 
 
-getrotate(s)				/* rotate camera */
-char  *s;
+void
+getrotate(				/* rotate camera */
+	char  *s
+)
 {
-	extern double  normalize(), tan(), atan();
-	VIEW  nv;
-	FVECT  v1;
+	VIEW  nv = ourview;
 	double  angle, elev, zfact;
 	
 	elev = 0.0; zfact = 1.0;
@@ -210,24 +344,19 @@ char  *s;
 		error(COMMAND, "missing angle");
 		return;
 	}
-	nv.type = ourview.type;
-	VCOPY(nv.vp, ourview.vp);
-	VCOPY(nv.vup, ourview.vup);
-	nv.hoff = ourview.hoff; nv.voff = ourview.voff;
 	spinvector(nv.vdir, ourview.vdir, ourview.vup, angle*(PI/180.));
-	if (elev != 0.0) {
-		fcross(v1, nv.vdir, ourview.vup);
-		normalize(v1);
-		spinvector(nv.vdir, nv.vdir, v1, elev*(PI/180.));
-	}
-	nv.horiz = ourview.horiz; nv.vert = ourview.vert;
+	if (elev != 0.0)
+		geodesic(nv.vdir, nv.vdir, nv.vup, elev*(PI/180.), GEOD_RAD);
+	
 	zoomview(&nv, zfact);
 	newview(&nv);
 }
 
 
-getpivot(s)				/* pivot viewpoint */
-register char  *s;
+void
+getpivot(				/* pivot viewpoint */
+	char  *s
+)
 {
 	FVECT  vc;
 	double  angle, elev, mag;
@@ -237,35 +366,84 @@ register char  *s;
 		error(COMMAND, "missing angle");
 		return;
 	}
-	if (getinterest(sskip(sskip(s)), 0, vc, &mag) < 0)
+	if (getinterest(sskip2(s,2), 0, vc, &mag) < 0)
 		return;
 	moveview(angle, elev, mag, vc);
 }
 
 
-getexposure(s)				/* get new exposure */
-char  *s;
+void
+getorigin(				/* origin viewpoint */
+	char  *s
+)
 {
-	double  atof(), pow(), fabs();
+	VIEW	nv = ourview;
+	double	d;
+					/* get new view origin */
+	if (!sscanvec(s, nv.vp)) {
+		int	x, y;
+		RAY	thisray;
+		if (dev->getcur == NULL)
+			return;
+		(*dev->comout)("Pick point on surface for new origin\n");
+		if ((*dev->getcur)(&x, &y) == ABORT)
+			return;
+		if ((thisray.rmax = viewray(thisray.rorg, thisray.rdir,
+			&ourview, (x+.5)/hresolu, (y+.5)/vresolu)) < -FTINY) {
+			error(COMMAND, "not on image");
+			return;
+		}
+		rayorigin(&thisray, PRIMARY, NULL, NULL);
+		if (!localhit(&thisray, &thescene)) {
+			error(COMMAND, "not a local object");
+			return;
+		}
+		if (thisray.rod < 0.0)	/* don't look through other side */
+			flipsurface(&thisray);
+		VSUM(nv.vp, thisray.rop, thisray.ron, 2.0*FTINY);
+		VCOPY(nv.vdir, thisray.ron);
+	} else if (!sscanvec(sskip2(s,3), nv.vdir) || normalize(nv.vdir) == 0.0)
+		VCOPY(nv.vdir, ourview.vdir);
+
+	d = DOT(nv.vdir, nv.vup);	/* need different up vector? */
+	if (d*d >= 1.-2.*FTINY) {
+		int	i;
+		nv.vup[0] = nv.vup[1] = nv.vup[2] = 0.0;
+		for (i = 3; i--; )
+			if (nv.vdir[i]*nv.vdir[i] < 0.34)
+				break;
+		nv.vup[i] = 1.;
+	}
+	newview(&nv);
+}
+
+
+void
+getexposure(				/* get new exposure */
+	char  *s
+)
+{
 	char  buf[128];
-	register char  *cp;
-	register PNODE  *p;
-	RECT  r;
+	char  *cp;
 	int  x, y;
-	double  e;
+	PNODE  *p = &ptrunk;
+	int  adapt = 0;
+	double  e = 1.0;
 
 	for (cp = s; isspace(*cp); cp++)
 		;
+	if (*cp == '@') {
+		adapt++;
+		while (isspace(*++cp))
+			;
+	}
 	if (*cp == '\0') {		/* normalize to point */
 		if (dev->getcur == NULL)
 			return;
 		(*dev->comout)("Pick point for exposure\n");
 		if ((*dev->getcur)(&x, &y) == ABORT)
 			return;
-		r.l = r.d = 0;
-		r.r = hresolu; r.u = vresolu;
-		p = findrect(x, y, &ptrunk, &r, -1);
-		e = 1.0;
+		p = findrect(x, y, &ptrunk, -1);
 	} else {
 		if (*cp == '=') {	/* absolute setting */
 			p = NULL;
@@ -273,7 +451,7 @@ char  *s;
 			for (cp++; isspace(*cp); cp++)
 				;
 			if (*cp == '\0') {	/* interactive */
-				sprintf(buf, "exposure (%lf): ", exposure);
+				sprintf(buf, "exposure (%f): ", exposure);
 				(*dev->comout)(buf);
 				(*dev->comin)(buf, NULL);
 				for (cp = buf; isspace(*cp); cp++)
@@ -281,9 +459,6 @@ char  *s;
 				if (*cp == '\0')
 					return;
 			}
-		} else {		/* normalize to average */
-			p = &ptrunk;
-			e = 1.0;
 		}
 		if (*cp == '+' || *cp == '-')	/* f-stops */
 			e *= pow(2.0, atof(cp));
@@ -291,11 +466,15 @@ char  *s;
 			e *= atof(cp);
 	}
 	if (p != NULL) {		/* relative setting */
-		if (bright(p->v) <= FTINY) {
+		compavg(p);
+		if (bright(p->v) < 1e-15) {
 			error(COMMAND, "cannot normalize to zero");
 			return;
 		}
-		e *= 0.5 / bright(p->v);
+		if (adapt)
+			e *= 106./pow(1.219+pow(luminance(p->v)/exposure,.4),2.5)/exposure;
+		else
+			e *= 0.5 / bright(p->v);
 	}
 	if (e <= FTINY || fabs(1.0 - e) <= FTINY)
 		return;
@@ -304,13 +483,18 @@ char  *s;
 	redraw();
 }
 
+typedef union {int i; double d; COLOR C;}	*MyUptr;
+#define  FEQ(x,y)     (fabs((x)-(y)) <= FTINY)
 
-getparam(str, dsc, typ, ptr)		/* get variable from user */
-char  *str, *dsc;
-int  typ;
-register union {int i; double d; COLOR C;}  *ptr;
+int
+getparam(		/* get variable from user */
+	char  *str,
+	char  *dsc,
+	int  typ,
+	void  *p
+)
 {
-	extern char  *index();
+	MyUptr  ptr = (MyUptr)p;
 	int  i0;
 	double  d0, d1, d2;
 	char  buf[48];
@@ -325,8 +509,10 @@ register union {int i; double d; COLOR C;}  *ptr;
 			if (sscanf(buf, "%d", &i0) != 1)
 				return(0);
 		}
+		if (ptr->i == i0)
+			return(0);
 		ptr->i = i0;
-		return(1);
+		break;
 	case 'r':			/* real */
 		if (sscanf(str, "%lf", &d0) != 1) {
 			(*dev->comout)(dsc);
@@ -336,20 +522,26 @@ register union {int i; double d; COLOR C;}  *ptr;
 			if (sscanf(buf, "%lf", &d0) != 1)
 				return(0);
 		}
+		if (FEQ(ptr->d, d0))
+			return(0);
 		ptr->d = d0;
-		return(1);
+		break;
 	case 'b':			/* boolean */
 		if (sscanf(str, "%1s", buf) != 1) {
 			(*dev->comout)(dsc);
-			sprintf(buf, " (%c): ", ptr->i ? 'y' : 'n');
+			sprintf(buf, "? (%c): ", ptr->i ? 'y' : 'n');
 			(*dev->comout)(buf);
 			(*dev->comin)(buf, NULL);
-			if (buf[0] == '\0' ||
-					index("yY+1tTnN-0fF", buf[0]) == NULL)
+			if (buf[0] == '\0')
 				return(0);
 		}
-		ptr->i = index("yY+1tT", buf[0]) != NULL;
-		return(1);
+		if (strchr("yY+1tTnN-0fF", buf[0]) == NULL)
+			return(0);
+		i0 = strchr("yY+1tT", buf[0]) != NULL;
+		if (ptr->i == i0)
+			return(0);
+		ptr->i = i0;
+		break;
 	case 'C':			/* color */
 		if (sscanf(str, "%lf %lf %lf", &d0, &d1, &d2) != 3) {
 			(*dev->comout)(dsc);
@@ -362,48 +554,48 @@ register union {int i; double d; COLOR C;}  *ptr;
 			if (sscanf(buf, "%lf %lf %lf", &d0, &d1, &d2) != 3)
 				return(0);
 		}
+		if (FEQ(colval(ptr->C,RED), d0) &&
+				FEQ(colval(ptr->C,GRN), d1) &&
+				FEQ(colval(ptr->C,BLU), d2))
+			return(0);
 		setcolor(ptr->C, d0, d1, d2);
-		return(1);
+		break;
+	default:
+		return(0);		/* shouldn't happen */
 	}
+	newparam++;
+	return(1);
 }
 
 
-setparam(s)				/* get/set program parameter */
-register char  *s;
+void
+setparam(				/* get/set program parameter */
+	char  *s
+)
 {
-	extern int  psample;
-	extern double  maxdiff;
-	extern double  minweight;
-	extern int  maxdepth;
-	extern double  dstrsrc;
-	extern double  shadthresh;
-	extern double  shadcert;
-	extern COLOR  ambval;
-	extern double  ambacc;
-	extern double  minarad;
-	extern int  ambres;
-	extern int  ambdiv;
-	extern int  ambssamp;
-	extern int  ambounce;
-	extern int  directinvis;
-	extern double  srcsizerat;
-	extern int  do_irrad;
+	int  prev_newp = newparam;
 	char  buf[128];
 	
 	if (s[0] == '\0') {
 		(*dev->comout)(
-			"aa ab ad ar as av b dc di dj ds dt i lr lw sp st: ");
+		"aa ab ad ar as av aw b bv dc dv dj ds dt i lr lw me ma mg ms ps pt ss st u: ");
 		(*dev->comin)(buf, NULL);
 		s = buf;
 	}
 	switch (s[0]) {
+	case 'u':			/* uncorrelated sampling */
+		getparam(s+1, "uncorrelated sampling", 'b',
+				(void *)&rand_samp);
+		break;
 	case 'l':			/* limit */
 		switch (s[1]) {
 		case 'w':			/* weight */
-			getparam(s+2, "limit weight", 'r', &minweight);
+			getparam(s+2, "limit weight", 'r',
+					(void *)&minweight);
 			break;
 		case 'r':			/* reflection */
-			getparam(s+2, "limit reflection", 'i', &maxdepth);
+			getparam(s+2, "limit reflection", 'i',
+					(void *)&maxdepth);
 			break;
 		default:
 			goto badparam;
@@ -412,71 +604,140 @@ register char  *s;
 	case 'd':			/* direct */
 		switch (s[1]) {
 		case 'j':			/* jitter */
-			getparam(s+2, "direct jitter", 'r', &dstrsrc);
+			getparam(s+2, "direct jitter", 'r',
+					(void *)&dstrsrc);
 			break;
 		case 'c':			/* certainty */
-			getparam(s+2, "direct certainty", 'r', &shadcert);
+			getparam(s+2, "direct certainty", 'r',
+					(void *)&shadcert);
 			break;
 		case 't':			/* threshold */
-			getparam(s+2, "direct threshold", 'r', &shadthresh);
+			getparam(s+2, "direct threshold", 'r',
+					(void *)&shadthresh);
 			break;
-		case 'i':			/* invisibility */
-			getparam(s+2, "direct invisibility",
-					'b', &directinvis);
+		case 'v':			/* visibility */
+			getparam(s+2, "direct visibility", 'b',
+					(void *)&directvis);
 			break;
 		case 's':			/* sampling */
-			getparam(s+2, "direct sampling", 'r', &srcsizerat);
+			getparam(s+2, "direct sampling", 'r',
+					(void *)&srcsizerat);
 			break;
 		default:
 			goto badparam;
 		}
 		break;
-	case 'b':			/* black and white */
-		getparam(s+1, "black and white", 'b', &greyscale);
+	case 'b':			/* back faces or black and white */
+		switch (s[1]) {
+		case 'v':			/* back face visibility */
+			getparam(s+2, "back face visibility", 'b',
+					(void *)&backvis);
+			break;
+		case '\0':			/* black and white */
+		case ' ':
+		case 'y': case 'Y': case 't': case 'T': case '1': case '+':
+		case 'n': case 'N': case 'f': case 'F': case '0': case '-':
+			getparam(s+1, "black and white", 'b',
+					(void *)&greyscale);
+			newparam = prev_newp;
+			break;
+		default:
+			goto badparam;
+		}
 		break;
 	case 'i':			/* irradiance */
-		getparam(s+1, "irradiance", 'b', &do_irrad);
+		getparam(s+1, "irradiance", 'b',
+				(void *)&do_irrad);
 		break;
 	case 'a':			/* ambient */
 		switch (s[1]) {
 		case 'v':			/* value */
-			getparam(s+2, "ambient value", 'C', ambval);
+			getparam(s+2, "ambient value", 'C',
+					(void *)ambval);
 			break;
+		case 'w':			/* weight */
+			getparam(s+2, "ambient value weight", 'i',
+					(void *)&ambvwt);
+			break;
 		case 'a':			/* accuracy */
-			getparam(s+2, "ambient accuracy", 'r', &ambacc);
+			if (getparam(s+2, "ambient accuracy", 'r',
+					(void *)&ambacc))
+				setambacc(ambacc);
 			break;
 		case 'd':			/* divisions */
-			getparam(s+2, "ambient divisions", 'i', &ambdiv);
+			getparam(s+2, "ambient divisions", 'i',
+					(void *)&ambdiv);
 			break;
 		case 's':			/* samples */
-			getparam(s+2, "ambient super-samples", 'i', &ambssamp);
+			getparam(s+2, "ambient super-samples", 'i',
+					(void *)&ambssamp);
 			break;
 		case 'b':			/* bounces */
-			getparam(s+2, "ambient bounces", 'i', &ambounce);
+			getparam(s+2, "ambient bounces", 'i',
+					(void *)&ambounce);
 			break;
 		case 'r':
-			if (getparam(s+2, "ambient resolution", 'i', &ambres))
-				minarad = ambres > 0 ?
-						thescene.cusize/ambres : 0.0;
+			if (getparam(s+2, "ambient resolution", 'i',
+					(void *)&ambres))
+				setambres(ambres);
 			break;
 		default:
 			goto badparam;
 		}
 		break;
-	case 's':			/* sample */
+	case 'm':			/* medium */
 		switch (s[1]) {
-		case 'p':			/* pixel */
-			if (getparam(s+2, "sample pixel", 'i', &psample))
+		case 'e':			/* extinction coefficient */
+			getparam(s+2, "extinction coefficient", 'C',
+					(void *)cextinction);
+			break;
+		case 'a':			/* scattering albedo */
+			getparam(s+2, "scattering albedo", 'C',
+					(void *)salbedo);
+			break;
+		case 'g':			/* scattering eccentricity */
+			getparam(s+2, "scattering eccentricity", 'r',
+					(void *)&seccg);
+			break;
+		case 's':			/* sampling distance */
+			getparam(s+2, "mist sampling distance", 'r',
+					(void *)&ssampdist);
+			break;
+		default:
+			goto badparam;
+		}
+		break;
+	case 'p':			/* pixel */
+		switch (s[1]) {
+		case 's':			/* sample */
+			if (getparam(s+2, "pixel sample", 'i',
+					(void *)&psample))
 				pdepth = 0;
 			break;
 		case 't':			/* threshold */
-			if (getparam(s+2, "sample threshold", 'r', &maxdiff))
+			if (getparam(s+2, "pixel threshold", 'r',
+					(void *)&maxdiff))
 				pdepth = 0;
 			break;
 		default:
 			goto badparam;
 		}
+		newparam = prev_newp;
 		break;
+	case 's':			/* specular */
+		switch (s[1]) {
+		case 's':			/* sampling */
+			getparam(s+2, "specular sampling", 'r',
+					(void *)&specjitter);
+			break;
+		case 't':			/* threshold */
+			getparam(s+2, "specular threshold", 'r',
+					(void *)&specthresh);
+			break;
+		default:
+			goto badparam;
+		}
+		break;
 	case '\0':			/* nothing */
 		break;
 	default:;
@@ -489,25 +750,28 @@ badparam:
 }
 
 
-traceray(s)				/* trace a single ray */
-char  *s;
+void
+traceray(				/* trace a single ray */
+	char  *s
+)
 {
-	char  buf[128];
-	int  x, y;
-	RAY  thisray;
+	RAY	thisray;
+	char	buf[512];
 
-	if (sscanf(s, "%lf %lf %lf %lf %lf %lf",
-		&thisray.rorg[0], &thisray.rorg[1], &thisray.rorg[2],
-		&thisray.rdir[0], &thisray.rdir[1], &thisray.rdir[2]) != 6) {
+	thisray.rmax = 0.0;
 
+	if (!sscanvec(s, thisray.rorg) ||
+			!sscanvec(sskip2(s,3), thisray.rdir)) {
+		int  x, y;
+
 		if (dev->getcur == NULL)
 			return;
 		(*dev->comout)("Pick ray\n");
 		if ((*dev->getcur)(&x, &y) == ABORT)
 			return;
 
-		if (viewray(thisray.rorg, thisray.rdir, &ourview,
-				(x+.5)/hresolu, (y+.5)/vresolu) < 0) {
+		if ((thisray.rmax = viewray(thisray.rorg, thisray.rdir,
+			&ourview, (x+.5)/hresolu, (y+.5)/vresolu)) < -FTINY) {
 			error(COMMAND, "not on image");
 			return;
 		}
@@ -517,28 +781,48 @@ char  *s;
 		return;
 	}
 
-	rayorigin(&thisray, NULL, PRIMARY, 1.0);
-	
-	rayvalue(&thisray);
+	ray_trace(&thisray);
 
 	if (thisray.ro == NULL)
 		(*dev->comout)("ray hit nothing");
 	else {
-		sprintf(buf, "ray hit %s %s \"%s\"",
-				objptr(thisray.ro->omod)->oname,
+		OBJREC	*mat = NULL;
+		OBJREC	*mod = NULL;
+		char	matspec[256];
+		OBJREC	*ino;
+
+		matspec[0] = '\0';
+		if (thisray.ro->omod != OVOID) {
+			mod = objptr(thisray.ro->omod);
+			mat = findmaterial(mod);
+		}
+		if (thisray.rod < 0.0)
+			strcpy(matspec, "back of ");
+		if (mod != NULL) {
+			strcat(matspec, mod->oname);
+			if (mat != mod && mat != NULL)
+				sprintf(matspec+strlen(matspec),
+					" (%s)", mat->oname);
+		} else
+			strcat(matspec, VOIDID);
+		sprintf(buf, "ray hit %s %s \"%s\"", matspec,
 				ofun[thisray.ro->otype].funame,
 				thisray.ro->oname);
+		if ((ino = objptr(thisray.robj)) != thisray.ro)
+			sprintf(buf+strlen(buf), " in %s \"%s\"",
+					ofun[ino->otype].funame, ino->oname);
 		(*dev->comout)(buf);
 		(*dev->comin)(buf, NULL);
 		if (thisray.rot >= FHUGE)
 			(*dev->comout)("at infinity");
 		else {
-			sprintf(buf, "at (%.6g %.6g %.6g)", thisray.rop[0],
-					thisray.rop[1], thisray.rop[2]);
+			sprintf(buf, "at (%.6g %.6g %.6g) (%.6g)",
+					thisray.rop[0], thisray.rop[1],
+					thisray.rop[2], thisray.rt);
 			(*dev->comout)(buf);
 		}
 		(*dev->comin)(buf, NULL);
-		sprintf(buf, "value (%.5g %.5g %.5g) (%.1fL)",
+		sprintf(buf, "value (%.5g %.5g %.5g) (%.3gL)",
 				colval(thisray.rcol,RED),
 				colval(thisray.rcol,GRN),
 				colval(thisray.rcol,BLU),
@@ -549,16 +833,18 @@ char  *s;
 }
 
 
-writepict(s)				/* write the picture to a file */
-char  *s;
+void
+writepict(				/* write the picture to a file */
+	char  *s
+)
 {
 	static char  buf[128];
 	char  *fname;
 	FILE  *fp;
 	COLR  *scanline;
 	int  y;
-
-	if (sscanf(s, "%s", buf) != 1 && buf[0] == '\0') {
+				/* XXX relies on words.c 2.11 behavior */
+	if (nextword(buf, sizeof(buf), s) == NULL && !buf[0]) {
 		error(COMMAND, "no file");
 		return;
 	}
@@ -568,10 +854,12 @@ char  *s;
 		error(COMMAND, errmsg);
 		return;
 	}
+	SET_FILE_BINARY(fp);
 	(*dev->comout)("writing \"");
 	(*dev->comout)(fname);
 	(*dev->comout)("\"...\n");
 						/* write header */
+	newheader("RADIANCE", fp);
 	fputs(progname, fp);
 	fprintview(&ourview, fp);
 	if (octname != NULL)
@@ -579,6 +867,7 @@ char  *s;
 	else
 		putc('\n', fp);
 	fprintf(fp, "SOFTWARE= %s\n", VersionID);
+	fputnow(fp);
 	if (exposure != 1.0)
 		fputexpos(exposure, fp);
 	if (dev->pixaspect != 1.0)
@@ -599,7 +888,7 @@ char  *s;
 		if (fwritecolrs(scanline, hresolu, fp) < 0)
 			break;
 	}
-	free((char *)scanline);
+	free((void *)scanline);
 	if (fclose(fp) < 0)
 		error(COMMAND, "write error");
 }