--- ray/src/rt/t_func.c	1989/02/02 10:41:46	1.1
+++ ray/src/rt/t_func.c	1991/08/08 11:29:51	1.9
@@ -1,4 +1,4 @@
-/* Copyright (c) 1986 Regents of the University of California */
+/* Copyright (c) 1990 Regents of the University of California */
 
 #ifndef lint
 static char SCCSid[] = "$SunId$ LBL";
@@ -28,22 +28,16 @@ static char SCCSid[] = "$SunId$ LBL";
  *  from the original coordinates to the current coordinates.
  */
 
-typedef struct {
-	struct {
-		double  sca;		/* scale factor */
-		double  xfm[4][4];	/* transformation matrix */
-	}  fore, back;
-}  XFORM;
 
-
 t_func(m, r)			/* compute texture for ray */
 register OBJREC  *m;
 register RAY  *r;
 {
-#define  mxf	((XFORM *)m->os)
 	extern double  varvalue();
 	extern int  errno;
 	FVECT  disp;
+	double  d;
+	register FULLXF  *mxf;
 	register int  i;
 	register char  **sa;
 
@@ -51,29 +45,22 @@ register RAY  *r;
 		objerror(m, USER, "bad # arguments");
 	sa = m->oargs.sarg;
 
-	if (mxf == NULL) {
-		mxf = (XFORM *)malloc(sizeof(XFORM));
+	if ((mxf = (FULLXF *)m->os) == NULL) {
+		mxf = (FULLXF *)malloc(sizeof(FULLXF));
 		if (mxf == NULL)
 			goto memerr;
-		mxf->fore.sca = 1.0;
-		setident4(mxf->fore.xfm);
-		if (xf(mxf->fore.xfm, &mxf->fore.sca,
-			m->oargs.nsargs-4, sa+4) != m->oargs.nsargs-4)
+		if (fullxf(mxf, m->oargs.nsargs-4, sa+4) != m->oargs.nsargs-4)
 			objerror(m, USER, "bad transform");
-		if (mxf->fore.sca < 0.0)
-			mxf->fore.sca = -mxf->fore.sca;
-		mxf->back.sca = 1.0;
-		setident4(mxf->back.xfm);
-		invxf(mxf->back.xfm, &mxf->back.sca,
-				m->oargs.nsargs-4, sa+4);
-		if (mxf->back.sca < 0.0)
-			mxf->back.sca = -mxf->back.sca;
+		if (mxf->f.sca < 0.0)
+			mxf->f.sca = -mxf->f.sca;
+		if (mxf->b.sca < 0.0)
+			mxf->b.sca = -mxf->b.sca;
+		m->os = (char *)mxf;
 	}
 
-	setmap(m, r, mxf->back.sca, mxf->back.xfm);
+	setmap(m, r, &mxf->b);
 
-	if (!vardefined(sa[0]))
-		loadfunc(sa[3]);
+	funcfile(sa[3]);
 	errno = 0;
 	for (i = 0; i < 3; i++)
 		disp[i] = varvalue(sa[i]);
@@ -81,17 +68,15 @@ register RAY  *r;
 		objerror(m, WARNING, "compute error");
 		return;
 	}
-	if (mxf->fore.xfm == NULL)
-		for (i = 0; i < 3; i++)
-			r->pert[i] += disp[i];
-	else
-		for (i = 0; i < 3; i++)
-			r->pert[i] += (	disp[0]*mxf->fore.xfm[0][i] +
-					disp[1]*mxf->fore.xfm[1][i] +
-					disp[2]*mxf->fore.xfm[2][i] )
-						/ mxf->fore.sca;
+	multv3(disp, disp, mxf->f.xfm);
+	if (r->rox != NULL) {
+		multv3(disp, disp, r->rox->f.xfm);
+		d = 1.0 / (mxf->f.sca * r->rox->f.sca);
+	} else
+		d = 1.0 / mxf->f.sca;
+	for (i = 0; i < 3; i++)
+		r->pert[i] += disp[i] * d;
 	return;
 memerr:
 	error(SYSTEM, "out of memory in t_func");
-#undef  mxf
 }