--- ray/src/rt/raycalls.c	2018/01/23 23:37:11	2.23
+++ ray/src/rt/raycalls.c	2023/02/02 18:55:09	2.28
@@ -1,5 +1,5 @@
 #ifndef lint
-static const char	RCSid[] = "$Id: raycalls.c,v 2.23 2018/01/23 23:37:11 greg Exp $";
+static const char	RCSid[] = "$Id: raycalls.c,v 2.28 2023/02/02 18:55:09 greg Exp $";
 #endif
 /*
  *  raycalls.c - interface for running Radiance rendering as a library
@@ -119,9 +119,11 @@ void	(*trace)() = NULL;		/* trace call */
 
 void	(*addobjnotify[8])() = {ambnotify, NULL};
 
+int	castonly = 0;			/* only doing ray-casting? */
+
 int	do_irrad = 0;			/* compute irradiance? */
 
-int	rand_samp = 0;			/* pure Monte Carlo sampling? */
+int	rand_samp = 1;			/* pure Monte Carlo sampling? */
 
 double	dstrsrc = 0.0;			/* square source distribution */
 double	shadthresh = .03;		/* shadow threshold */
@@ -141,8 +143,8 @@ double	specjitter = 1.;		/* specular sampling jitter *
 
 int	backvis = 1;			/* back face visibility */
 
-int	maxdepth = 8;			/* maximum recursion depth */
-double	minweight = 5e-4;		/* minimum ray weight */
+int	maxdepth = -10;			/* maximum recursion depth */
+double	minweight = 1e-4;		/* minimum ray weight */
 
 char	*ambfile = NULL;		/* ambient file name */
 COLOR	ambval = BLKCOLOR;		/* ambient value */
@@ -156,6 +158,19 @@ char	*amblist[AMBLLEN+1];		/* ambient include/exclude 
 int	ambincl = -1;			/* include == 1, exclude == 0 */
 
 
+static void
+reset_random(void)		/* re-initialize random number generator */
+{
+	if (rand_samp) {
+		srandom((long)time(0));
+		initurand(0);
+	} else {
+		srandom(0L);
+		initurand(2048);
+	}
+}
+
+
 void
 ray_init(			/* initialize ray-tracing calculation */
 	char	*otnm
@@ -167,25 +182,24 @@ ray_init(			/* initialize ray-tracing calculation */
 	if (ofun[OBJ_SPHERE].funp == o_default)
 		initotypes();
 					/* initialize urand */
-	if (rand_samp) {
-		srandom((long)time(0));
-		initurand(0);
-	} else {
-		srandom(0L);
-		initurand(2048);
-	}
-					/* read scene octree */
-	readoct(octname = otnm, ~(IO_FILES|IO_INFO), &thescene, NULL);
+	reset_random();
+
+	octname = savqstr(otnm);	/* read scene octree */
+	readoct(octname, ~(IO_FILES|IO_INFO), &thescene, NULL);
 	nsceneobjs = nobjects;
-					/* PMAP: Init & load photon maps */
-	ray_init_pmap();
-					/* find and mark sources */
-	marksources();
-					/* initialize ambient calculation */
-	setambient();
-					/* ready to go... (almost) */
+
+	if (!castonly) {		/* any actual ray traversal to do? */
+
+		ray_init_pmap();	/* PMAP: set up & load photon maps */
+
+		marksources();		/* find and mark sources */
+
+		setambient();		/* initialize ambient calculation */
+	} else
+		distantsources();	/* else mark only distant sources */
 }
 
+
 void
 ray_trace(			/* trace a primary ray */
 	RAY	*r
@@ -210,7 +224,7 @@ ray_done(		/* free ray-tracing data */
 	donesets();
 	octdone();
 	thescene.cutree = EMPTY;
-	octname = NULL;
+	freeqstr(octname); octname = NULL;
 	retainfonts = 0;
 	if (freall) {
 		freefont(NULL);
@@ -238,6 +252,7 @@ ray_save(			/* save current parameter settings */
 	if (rp == NULL)
 		return;
 	rp->do_irrad = do_irrad;
+	rp->rand_samp = rand_samp;
 	rp->dstrsrc = dstrsrc;
 	rp->shadthresh = shadthresh;
 	rp->shadcert = shadcert;
@@ -254,10 +269,11 @@ ray_save(			/* save current parameter settings */
 	rp->backvis = backvis;
 	rp->maxdepth = maxdepth;
 	rp->minweight = minweight;
-	copycolor(rp->ambval, ambval);
-	memset(rp->ambfile, '\0', sizeof(rp->ambfile));
 	if (ambfile != NULL)
 		strncpy(rp->ambfile, ambfile, sizeof(rp->ambfile)-1);
+	else
+		memset(rp->ambfile, '\0', sizeof(rp->ambfile));
+	copycolor(rp->ambval, ambval);
 	rp->ambvwt = ambvwt;
 	rp->ambacc = ambacc;
 	rp->ambres = ambres;
@@ -288,7 +304,7 @@ ray_restore(			/* restore parameter settings */
 	RAYPARAMS	*rp
 )
 {
-	register int	i;
+	int	i;
 
 	if (rp == NULL) {		/* restore defaults */
 		RAYPARAMS	dflt;
@@ -298,6 +314,10 @@ ray_restore(			/* restore parameter settings */
 	}
 					/* restore saved settings */
 	do_irrad = rp->do_irrad;
+	if (!rand_samp != !rp->rand_samp) {
+		rand_samp = rp->rand_samp;
+		reset_random();
+	}
 	dstrsrc = rp->dstrsrc;
 	shadthresh = rp->shadthresh;
 	shadcert = rp->shadcert;
@@ -319,6 +339,7 @@ ray_restore(			/* restore parameter settings */
 	ambdiv = rp->ambdiv;
 	ambssamp = rp->ambssamp;
 	ambounce = rp->ambounce;
+					/* a bit dangerous if not static */
 	for (i = 0; rp->amblndx[i] >= 0; i++)
 		amblist[i] = rp->amblval + rp->amblndx[i];
 	while (i <= AMBLLEN)
@@ -365,9 +386,10 @@ ray_defaults(		/* get default parameter values */
 		return;
 
 	rp->do_irrad = 0;
+	rp->rand_samp = 1;
 	rp->dstrsrc = 0.0;
-	rp->shadthresh = .03;
-	rp->shadcert = .75;
+	rp->shadthresh = 0.03;
+	rp->shadcert = 0.75;
 	rp->directrelay = 2;
 	rp->vspretest = 512;
 	rp->directvis = 1;
@@ -376,16 +398,16 @@ ray_defaults(		/* get default parameter values */
 	setcolor(rp->salbedo, 0., 0., 0.);
 	rp->seccg = 0.;
 	rp->ssampdist = 0.;
-	rp->specthresh = .15;
+	rp->specthresh = 0.15;
 	rp->specjitter = 1.;
 	rp->backvis = 1;
-	rp->maxdepth = 8;
-	rp->minweight = 2e-3;
-	setcolor(rp->ambval, 0., 0., 0.);
+	rp->maxdepth = -10;
+	rp->minweight = 1e-4;
 	memset(rp->ambfile, '\0', sizeof(rp->ambfile));
+	setcolor(rp->ambval, 0., 0., 0.);
 	rp->ambvwt = 0;
 	rp->ambres = 256;
-	rp->ambacc = 0.15;
+	rp->ambacc = 0.1;
 	rp->ambdiv = 1024;
 	rp->ambssamp = 512;
 	rp->ambounce = 0;