--- ray/src/gen/gensurf.c	1991/08/13 16:07:14	1.15
+++ ray/src/gen/gensurf.c	2003/02/22 02:07:23	2.6
@@ -1,9 +1,6 @@
 #ifndef lint
-static char SCCSid[] = "$SunId$ LBL";
+static const char	RCSid[] = "$Id: gensurf.c,v 2.6 2003/02/22 02:07:23 greg Exp $";
 #endif
-
-/* Copyright (c) 1989 Regents of the University of California */
-
 /*
  *  gensurf.c - program to generate functional surfaces
  *
@@ -14,14 +11,18 @@ static char SCCSid[] = "$SunId$ LBL";
  *  rule applied to (s,t).
  *
  *	4/3/87
+ *
+ *	4/16/02	Added conditional vertex output
  */
 
 #include  "standard.h"
 
-#define  XNAME		"X`SYS`"		/* x function name */
-#define  YNAME		"Y`SYS`"		/* y function name */
-#define  ZNAME		"Z`SYS`"		/* z function name */
+char  XNAME[] =		"X`SYS";		/* x function name */
+char  YNAME[] =		"Y`SYS";		/* y function name */
+char  ZNAME[] =		"Z`SYS";		/* z function name */
 
+char  VNAME[] = 	"valid";		/* valid vertex name */
+
 #define  ABS(x)		((x)>=0 ? (x) : -(x))
 
 #define  pvect(p)	printf(vformat, (p)[0], (p)[1], (p)[2])
@@ -34,9 +35,21 @@ int  smooth = 0;		/* apply smoothing? */
 
 char  *modname, *surfname;
 
-double  funvalue(), l_hermite(), l_bezier(), l_bspline(), argument();
+				/* recorded data flags */
+#define  HASBORDER	01
+#define  TRIPLETS	02
+				/* a data structure */
+struct {
+	int	flags;			/* data type */
+	short	m, n;			/* number of s and t values */
+	FLOAT	*data;			/* the data itself, s major sort */
+} datarec;			/* our recorded data */
 
+double  l_hermite(), l_bezier(), l_bspline(), l_dataval();
+extern double  funvalue(), argument();
+
 typedef struct {
+	int  valid;	/* point is valid */
 	FVECT  p;	/* vertex position */
 	FVECT  n;	/* average normal */
 } POINT;
@@ -71,17 +84,31 @@ char  *argv[];
 
 	modname = argv[1];
 	surfname = argv[2];
-	sprintf(stmp, "%s(s,t)=%s;", XNAME, argv[3]);
-	scompile(stmp, NULL, 0);
-	sprintf(stmp, "%s(s,t)=%s;", YNAME, argv[4]);
-	scompile(stmp, NULL, 0);
-	sprintf(stmp, "%s(s,t)=%s;", ZNAME, argv[5]);
-	scompile(stmp, NULL, 0);
 	m = atoi(argv[6]);
 	n = atoi(argv[7]);
 	if (m <= 0 || n <= 0)
 		goto userror;
-
+	if (!strcmp(argv[5], "-") || access(argv[5], 4) == 0) {	/* file? */
+		funset(ZNAME, 2, ':', l_dataval);
+		if (!strcmp(argv[5],argv[3]) && !strcmp(argv[5],argv[4])) {
+			loaddata(argv[5], m, n, 3);
+			funset(XNAME, 2, ':', l_dataval);
+			funset(YNAME, 2, ':', l_dataval);
+		} else {
+			loaddata(argv[5], m, n, 1);
+			sprintf(stmp, "%s(s,t)=%s;", XNAME, argv[3]);
+			scompile(stmp, NULL, 0);
+			sprintf(stmp, "%s(s,t)=%s;", YNAME, argv[4]);
+			scompile(stmp, NULL, 0);
+		}
+	} else {
+		sprintf(stmp, "%s(s,t)=%s;", XNAME, argv[3]);
+		scompile(stmp, NULL, 0);
+		sprintf(stmp, "%s(s,t)=%s;", YNAME, argv[4]);
+		scompile(stmp, NULL, 0);
+		sprintf(stmp, "%s(s,t)=%s;", ZNAME, argv[5]);
+		scompile(stmp, NULL, 0);
+	}
 	row0 = (POINT *)malloc((n+3)*sizeof(POINT));
 	row1 = (POINT *)malloc((n+3)*sizeof(POINT));
 	row2 = (POINT *)malloc((n+3)*sizeof(POINT));
@@ -109,8 +136,13 @@ char  *argv[];
 		compnorms(row0, row1, row2, n);
 
 		for (j = 0; j < n; j++) {
+			int  orient = (j & 1);
 							/* put polygons */
-			if ((i+j) & 1)
+			if (!(row0[j].valid & row1[j+1].valid))
+				orient = 1;
+			else if (!(row1[j].valid & row0[j+1].valid))
+				orient = 0;
+			if (orient)
 				putsquare(&row0[j], &row1[j],
 						&row0[j+1], &row1[j+1]);
 			else
@@ -128,6 +160,106 @@ userror:
 }
 
 
+loaddata(file, m, n, pointsize)		/* load point data from file */
+char  *file;
+int  m, n;
+int  pointsize;
+{
+	FILE  *fp;
+	char  word[64];
+	register int  size;
+	register FLOAT  *dp;
+
+	datarec.flags = HASBORDER;		/* assume border values */
+	datarec.m = m+1;
+	datarec.n = n+1;
+	size = datarec.m*datarec.n*pointsize;
+	if (pointsize == 3)
+		datarec.flags |= TRIPLETS;
+	dp = (FLOAT *)malloc(size*sizeof(FLOAT));
+	if ((datarec.data = dp) == NULL) {
+		fputs("Out of memory\n", stderr);
+		exit(1);
+	}
+	if (!strcmp(file, "-")) {
+		file = "<stdin>";
+		fp = stdin;
+	} else if ((fp = fopen(file, "r")) == NULL) {
+		fputs(file, stderr);
+		fputs(": cannot open\n", stderr);
+		exit(1);
+	}
+	while (size > 0 && fgetword(word, sizeof(word), fp) != NULL) {
+		if (!isflt(word)) {
+			fprintf(stderr, "%s: garbled data value: %s\n",
+					file, word);
+			exit(1);
+		}
+		*dp++ = atof(word);
+		size--;
+	}
+	if (size == (m+n+1)*pointsize) {	/* no border after all */
+		dp = (FLOAT *)realloc((char *)datarec.data,
+				m*n*pointsize*sizeof(FLOAT));
+		if (dp != NULL)
+			datarec.data = dp;
+		datarec.flags &= ~HASBORDER;
+		datarec.m = m;
+		datarec.n = n;
+		size = 0;
+	}
+	if (datarec.m < 2 || datarec.n < 2 || size != 0 ||
+			fgetword(word, sizeof(word), fp) != NULL) {
+		fputs(file, stderr);
+		fputs(": bad number of data points\n", stderr);
+		exit(1);
+	}
+	fclose(fp);
+}
+
+
+double
+l_dataval(nam)				/* return recorded data value */
+char  *nam;
+{
+	double  u, v;
+	register int  i, j;
+	register FLOAT  *dp;
+	double  d00, d01, d10, d11;
+						/* compute coordinates */
+	u = argument(1); v = argument(2);
+	if (datarec.flags & HASBORDER) {
+		i = u *= datarec.m-1;
+		j = v *= datarec.n-1;
+	} else {
+		i = u = u*datarec.m - .5;
+		j = v = v*datarec.n - .5;
+	}
+	if (i < 0) i = 0;
+	else if (i > datarec.m-2) i = datarec.m-2;
+	if (j < 0) j = 0;
+	else if (j > datarec.n-2) j = datarec.n-2;
+						/* compute value */
+	if (datarec.flags & TRIPLETS) {
+		dp = datarec.data + 3*(j*datarec.m + i);
+		if (nam == ZNAME)
+			dp += 2;
+		else if (nam == YNAME)
+			dp++;
+		d00 = dp[0]; d01 = dp[3];
+		dp += 3*datarec.m;
+		d10 = dp[0]; d11 = dp[3];
+	} else {
+		dp = datarec.data + j*datarec.m + i;
+		d00 = dp[0]; d01 = dp[1];
+		dp += datarec.m;
+		d10 = dp[0]; d11 = dp[1];
+	}
+						/* bilinear interpolation */
+	return((j+1-v)*((i+1-u)*d00+(u-i)*d01)+(v-j)*((i+1-u)*d10+(u-i)*d11));
+}
+
+
 putsquare(p0, p1, p2, p3)		/* put out a square */
 POINT  *p0, *p1, *p2, *p3;
 {
@@ -137,14 +269,20 @@ POINT  *p0, *p1, *p2, *p3;
 	FVECT  v1, v2, vc1, vc2;
 	int  ok1, ok2;
 					/* compute exact normals */
-	fvsum(v1, p1->p, p0->p, -1.0);
-	fvsum(v2, p2->p, p0->p, -1.0);
-	fcross(vc1, v1, v2);
-	ok1 = normalize(vc1) != 0.0;
-	fvsum(v1, p2->p, p3->p, -1.0);
-	fvsum(v2, p1->p, p3->p, -1.0);
-	fcross(vc2, v1, v2);
-	ok2 = normalize(vc2) != 0.0;
+	ok1 = (p0->valid & p1->valid & p2->valid);
+	if (ok1) {
+		fvsum(v1, p1->p, p0->p, -1.0);
+		fvsum(v2, p2->p, p0->p, -1.0);
+		fcross(vc1, v1, v2);
+		ok1 = (normalize(vc1) != 0.0);
+	}
+	ok2 = (p1->valid & p2->valid & p3->valid);
+	if (ok2) {
+		fvsum(v1, p2->p, p3->p, -1.0);
+		fvsum(v2, p1->p, p3->p, -1.0);
+		fcross(vc2, v1, v2);
+		ok2 = (normalize(vc2) != 0.0);
+	}
 	if (!(ok1 | ok2))
 		return;
 					/* compute normal interpolation */
@@ -222,6 +360,7 @@ int  siz;
 {
 	double  st[2];
 	int  end;
+	int  checkvalid;
 	register int  i;
 	
 	if (smooth) {
@@ -234,11 +373,18 @@ int  siz;
 		end = siz;
 	}
 	st[0] = s;
+	checkvalid = (fundefined(VNAME) == 2);
 	while (i <= end) {
 		st[1] = (double)i/siz;
-		row[i].p[0] = funvalue(XNAME, 2, st);
-		row[i].p[1] = funvalue(YNAME, 2, st);
-		row[i].p[2] = funvalue(ZNAME, 2, st);
+		if (checkvalid && funvalue(VNAME, 2, st) <= 0.0) {
+			row[i].valid = 0;
+			row[i].p[0] = row[i].p[1] = row[i].p[2] = 0.0;
+		} else {
+			row[i].valid = 1;
+			row[i].p[0] = funvalue(XNAME, 2, st);
+			row[i].p[1] = funvalue(YNAME, 2, st);
+			row[i].p[2] = funvalue(ZNAME, 2, st);
+		}
 		i++;
 	}
 }
@@ -249,14 +395,33 @@ register POINT  *r0, *r1, *r2;
 int  siz;
 {
 	FVECT  v1, v2;
-	register int  i;
 
 	if (!smooth)			/* not needed if no smoothing */
 		return;
-					/* compute middle points */
+					/* compute row 1 normals */
 	while (siz-- >= 0) {
-		fvsum(v1, r2[0].p, r0[0].p, -1.0);
-		fvsum(v2, r1[1].p, r1[-1].p, -1.0);
+		if (!r1[0].valid)
+			continue;
+		if (!r0[0].valid) {
+			if (!r2[0].valid) {
+				r1[0].n[0] = r1[0].n[1] = r1[0].n[2] = 0.0;
+				continue;
+			}
+			fvsum(v1, r2[0].p, r1[0].p, -1.0);
+		} else if (!r2[0].valid)
+			fvsum(v1, r1[0].p, r0[0].p, -1.0);
+		else
+			fvsum(v1, r2[0].p, r0[0].p, -1.0);
+		if (!r1[-1].valid) {
+			if (!r1[1].valid) {
+				r1[0].n[0] = r1[0].n[1] = r1[0].n[2] = 0.0;
+				continue;
+			}
+			fvsum(v2, r1[1].p, r1[0].p, -1.0);
+		} else if (!r1[1].valid)
+			fvsum(v2, r1[0].p, r1[-1].p, -1.0);
+		else
+			fvsum(v2, r1[1].p, r1[-1].p, -1.0);
 		fcross(r1[0].n, v1, v2);
 		normalize(r1[0].n);
 		r0++; r1++; r2++;
@@ -304,7 +469,7 @@ POINT  *p0, *p1, *p2, *p3;
 	eqnmat[3][2] = p3->p[v];
 	eqnmat[3][3] = 1.0;
 					/* invert matrix (solve system) */
-	if (!invmat(eqnmat, eqnmat))
+	if (!invmat4(eqnmat, eqnmat))
 		return(-1);			/* no solution */
 					/* compute result matrix */
 	for (j = 0; j < 4; j++)
@@ -320,64 +485,7 @@ POINT  *p0, *p1, *p2, *p3;
 }
 
 
-/*
- * invmat - computes the inverse of mat into inverse.  Returns 1
- * if there exists an inverse, 0 otherwise.  It uses Gaussian Elimination
- * method.
- */
-
-invmat(inverse,mat)
-MAT4  inverse, mat;
-{
-#define SWAP(a,b,t) (t=a,a=b,b=t)
-
-	MAT4  m4tmp;
-	register int i,j,k;
-	register double temp;
-
-	copymat4(m4tmp, mat);
-					/* set inverse to identity */
-	for (i = 0; i < 4; i++)
-		for (j = 0; j < 4; j++)
-			inverse[i][j] = i==j ? 1.0 : 0.0;
-
-	for(i = 0; i < 4; i++) {
-		/* Look for row with largest pivot and swap rows */
-		temp = FTINY; j = -1;
-		for(k = i; k < 4; k++)
-			if(ABS(m4tmp[k][i]) > temp) {
-				temp = ABS(m4tmp[k][i]);
-				j = k;
-				}
-		if(j == -1)	/* No replacing row -> no inverse */
-			return(0);
-		if (j != i)
-			for(k = 0; k < 4; k++) {
-				SWAP(m4tmp[i][k],m4tmp[j][k],temp);
-				SWAP(inverse[i][k],inverse[j][k],temp);
-				}
-
-		temp = m4tmp[i][i];
-		for(k = 0; k < 4; k++) {
-			m4tmp[i][k] /= temp;
-			inverse[i][k] /= temp;
-			}
-		for(j = 0; j < 4; j++) {
-			if(j != i) {
-				temp = m4tmp[j][i];
-				for(k = 0; k < 4; k++) {
-					m4tmp[j][k] -= m4tmp[i][k]*temp;
-					inverse[j][k] -= inverse[i][k]*temp;
-					}
-				}
-			}
-		}
-	return(1);
-
-#undef SWAP
-}
-
-
+void
 eputs(msg)
 char  *msg;
 {
@@ -385,6 +493,7 @@ char  *msg;
 }
 
 
+void
 wputs(msg)
 char  *msg;
 {
@@ -392,7 +501,9 @@ char  *msg;
 }
 
 
+void
 quit(code)
+int  code;
 {
 	exit(code);
 }