--- ray/src/rt/raycalls.c	2005/04/19 01:15:06	2.11
+++ ray/src/rt/raycalls.c	2009/12/12 05:20:10	2.17
@@ -1,5 +1,5 @@
 #ifndef lint
-static const char	RCSid[] = "$Id: raycalls.c,v 2.11 2005/04/19 01:15:06 greg Exp $";
+static const char	RCSid[] = "$Id: raycalls.c,v 2.17 2009/12/12 05:20:10 greg Exp $";
 #endif
 /*
  *  raycalls.c - interface for running Radiance rendering as a library
@@ -90,6 +90,7 @@ static const char	RCSid[] = "$Id: raycalls.c,v 2.11 20
  */
 
 #include <string.h>
+#include <time.h>
 
 #include  "ray.h"
 #include  "source.h"
@@ -118,6 +119,8 @@ void	(*addobjnotify[8])() = {ambnotify, NULL};
 
 int	do_irrad = 0;			/* compute irradiance? */
 
+int	rand_samp = 0;			/* pure Monte Carlo sampling? */
+
 double	dstrsrc = 0.0;			/* square source distribution */
 double	shadthresh = .03;		/* shadow threshold */
 double	shadcert = .75;			/* shadow certainty */
@@ -151,7 +154,7 @@ char	*amblist[AMBLLEN+1];		/* ambient include/exclude 
 int	ambincl = -1;			/* include == 1, exclude == 0 */
 
 
-extern void
+void
 ray_init(			/* initialize ray-tracing calculation */
 	char	*otnm
 )
@@ -162,7 +165,13 @@ ray_init(			/* initialize ray-tracing calculation */
 	if (ofun[OBJ_SPHERE].funp == o_default)
 		initotypes();
 					/* initialize urand */
-	initurand(2048);
+	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);
 	nsceneobjs = nobjects;
@@ -173,7 +182,7 @@ ray_init(			/* initialize ray-tracing calculation */
 					/* ready to go... */
 }
 
-extern void
+void
 ray_trace(			/* trace a primary ray */
 	RAY	*r
 )
@@ -184,7 +193,7 @@ ray_trace(			/* trace a primary ray */
 }
 
 
-extern void
+void
 ray_done(		/* free ray-tracing data */
 	int	freall
 )
@@ -212,7 +221,7 @@ ray_done(		/* free ray-tracing data */
 }
 
 
-extern void
+void
 ray_save(			/* save current parameter settings */
 	RAYPARAMS	*rp
 )
@@ -263,7 +272,7 @@ ray_save(			/* save current parameter settings */
 }
 
 
-extern void
+void
 ray_restore(			/* restore parameter settings */
 	RAYPARAMS	*rp
 )
@@ -331,7 +340,7 @@ ray_restore(			/* restore parameter settings */
 }
 
 
-extern void
+void
 ray_defaults(		/* get default parameter values */
 	RAYPARAMS	*rp
 )