--- ray/src/rt/m_direct.c	1995/09/07 12:35:21	2.6
+++ ray/src/rt/m_direct.c	2023/11/15 18:02:53	2.17
@@ -1,20 +1,17 @@
-/* Copyright (c) 1994 Regents of the University of California */
-
 #ifndef lint
-static char SCCSid[] = "$SunId$ LBL";
+static const char	RCSid[] = "$Id: m_direct.c,v 2.17 2023/11/15 18:02:53 greg Exp $";
 #endif
-
 /*
  * Routines for light-redirecting materials and
  *   their associated virtual light sources
  */
 
-#include  "ray.h"
+#include "copyright.h"
 
+#include  "ray.h"
 #include  "otypes.h"
-
+#include  "rtotypes.h"
 #include  "source.h"
-
 #include  "func.h"
 
 /*
@@ -31,8 +28,9 @@ static char SCCSid[] = "$SunId$ LBL";
  *	n A1 A2 .. An
  */
 
+static int redirect(OBJREC  *m, RAY  *r, int  n);
+static int dir_proj(MAT4  pm, OBJREC  *o, SRCREC  *s, int  n);
 
-int  dir_proj();
 VSMATERIAL  direct1_vs = {dir_proj, 1};
 VSMATERIAL  direct2_vs = {dir_proj, 2};
 
@@ -41,9 +39,11 @@ VSMATERIAL  direct2_vs = {dir_proj, 2};
 				getfunc(m, 8, 0xff, 1) )
 
 
-m_direct(m, r)			/* shade redirected ray */
-register OBJREC  *m;
-register RAY  *r;
+int
+m_direct(			/* shade redirected ray */
+	OBJREC  *m,
+	RAY  *r
+)
 {
 					/* check if source ray */
 	if (r->rsrc >= 0 && source[r->rsrc].so != r->ro)
@@ -60,23 +60,25 @@ register RAY  *r;
 }
 
 
-redirect(m, r, n)		/* compute n'th ray redirection */
-OBJREC  *m;
-RAY  *r;
-int  n;
+static int
+redirect(		/* compute n'th ray redirection */
+	OBJREC  *m,
+	RAY  *r,
+	int  n
+)
 {
 	MFUNC  *mf;
-	register EPNODE  **va;
+	EPNODE  **va;
 	FVECT  nsdir;
 	RAY  nr;
 	double  coef;
-	register int  j;
+	int  j;
 					/* set up function */
 	mf = getdfunc(m);
 	setfunc(m, r);
 					/* assign direction variable */
 	if (r->rsrc >= 0) {
-		register SRCREC  *sp = source + source[r->rsrc].sa.sv.sn;
+		SRCREC  *sp = source + source[r->rsrc].sa.sv.sn;
 
 		if (sp->sflags & SDISTANT)
 			VCOPY(nsdir, sp->sloc);
@@ -98,18 +100,19 @@ int  n;
 	errno = 0;
 	va = mf->ep + 4*n;
 	coef = evalue(va[0]);
-	if (errno)
+	if ((errno == EDOM) | (errno == ERANGE))
 		goto computerr;
-	if (coef <= FTINY || rayorigin(&nr, r, TRANS, coef) < 0)
+	setscolor(nr.rcoef, coef, coef, coef);
+	if (rayorigin(&nr, TRANS, r, nr.rcoef) < 0)
 		return(0);
 	va++;				/* compute direction */
 	for (j = 0; j < 3; j++) {
 		nr.rdir[j] = evalue(va[j]);
-		if (errno)
+		if (errno == EDOM || errno == ERANGE)
 			goto computerr;
 	}
-	if (mf->f != &unitxf)
-		multv3(nr.rdir, nr.rdir, mf->f->xfm);
+	if (mf->fxp != &unitxf)
+		multv3(nr.rdir, nr.rdir, mf->fxp->xfm);
 	if (r->rox != NULL)
 		multv3(nr.rdir, nr.rdir, r->rox->f.xfm);
 	if (normalize(nr.rdir) == 0.0)
@@ -118,8 +121,10 @@ int  n;
 	if (r->rsrc >= 0)
 		nr.rsrc = source[r->rsrc].sa.sv.sn;
 	rayvalue(&nr);
-	scalecolor(nr.rcol, coef);
-	addcolor(r->rcol, nr.rcol);
+	smultscolor(nr.rcol, nr.rcoef);
+	saddscolor(r->rcol, nr.rcol);
+	if (r->ro != NULL && isflat(r->ro->otype))
+		r->rxt = r->rot + raydistance(&nr);
 	return(1);
 computerr:
 	objerror(m, WARNING, "compute error");
@@ -127,11 +132,13 @@ computerr:
 }
 
 
-dir_proj(pm, o, s, n)		/* compute a director's projection */
-MAT4  pm;
-OBJREC  *o;
-SRCREC  *s;
-int  n;
+static int
+dir_proj(		/* compute a director's projection */
+	MAT4  pm,
+	OBJREC  *o,
+	SRCREC  *s,
+	int  n
+)
 {
 	RAY  tr;
 	OBJREC  *m;
@@ -139,7 +146,7 @@ int  n;
 	EPNODE  **va;
 	FVECT  cent, newdir, nv, h;
 	double  coef, olddot, newdot, od;
-	register int  i, j;
+	int  i, j;
 				/* initialize test ray */
 	getmaxdisk(cent, o);
 	if (s->sflags & SDISTANT)
@@ -160,7 +167,7 @@ int  n;
 	if (olddot <= FTINY && olddot >= -FTINY)
 		return(0);		/* old dir parallels plane */
 	tr.rmax = 0.0;
-	rayorigin(&tr, NULL, PRIMARY, 1.0);
+	rayorigin(&tr, PRIMARY, NULL, NULL);
 	if (!(*ofun[o->otype].funp)(o, &tr))
 		return(0);		/* no intersection! */
 				/* compute redirection */
@@ -173,18 +180,18 @@ int  n;
 	errno = 0;
 	va = mf->ep + 4*n;
 	coef = evalue(va[0]);
-	if (errno)
+	if (errno == EDOM || errno == ERANGE)
 		goto computerr;
 	if (coef <= FTINY)
 		return(0);		/* insignificant */
 	va++;
 	for (i = 0; i < 3; i++) {
 		newdir[i] = evalue(va[i]);
-		if (errno)
+		if (errno == EDOM || errno == ERANGE)
 			goto computerr;
 	}
-	if (mf->f != &unitxf)
-		multv3(newdir, newdir, mf->f->xfm);
+	if (mf->fxp != &unitxf)
+		multv3(newdir, newdir, mf->fxp->xfm);
 					/* normalization unnecessary */
 	newdot = DOT(newdir, nv);
 	if (newdot <= FTINY && newdot >= -FTINY)
@@ -198,7 +205,7 @@ int  n;
 			pm[i][j] += nv[i]*h[j];
 		pm[3][j] = -od*h[j];
 	}
-	if (newdot > 0.0 ^ olddot > 0.0)	/* add mirroring */
+	if ((newdot > 0.0) ^ (olddot > 0.0))	/* add mirroring */
 		for (j = 0; j < 3; j++) {
 			for (i = 0; i < 3; i++)
 				pm[i][j] -= 2.*nv[i]*nv[j];