--- ray/src/rt/data.c	1989/02/02 10:41:18	1.1
+++ ray/src/rt/data.c	1991/07/22 13:02:24	1.10
@@ -1,4 +1,4 @@
-/* Copyright (c) 1986 Regents of the University of California */
+/* Copyright (c) 1991 Regents of the University of California */
 
 #ifndef lint
 static char SCCSid[] = "$SunId$ LBL";
@@ -17,6 +17,9 @@ static char SCCSid[] = "$SunId$ LBL";
 #include  "data.h"
 
 
+extern char  *fgetword();
+extern double  atof();
+
 extern char  *libpath;			/* library search path */
 
 static DATARRAY  *dlist = NULL;		/* data array list */
@@ -28,10 +31,11 @@ DATARRAY *
 getdata(dname)				/* get data array dname */
 char  *dname;
 {
+	char  word[64];
 	char  *dfname;
 	FILE  *fp;
 	int  asize;
-	register int  i;
+	register int  i, j;
 	register DATARRAY  *dp;
 						/* look for array in list */
 	for (dp = dlist; dp != NULL; dp = dp->next)
@@ -44,16 +48,21 @@ char  *dname;
 	 *
 	 *	The file has the following format:
 	 *
-	 *		#dimensions
+	 *		N
 	 *		beg0	end0	n0
 	 *		beg1	end1	n1
 	 *		. . .
+	 *		begN	endN	nN
 	 *		data, later dimensions changing faster
 	 *		. . .
 	 *
+	 *	For irregularly spaced points, the following can be
+	 *  substituted for begi endi ni:
+	 *
+	 *		0 0 ni p0i p1i .. pni
 	 */
 
-	if ((dfname = getpath(dname, libpath)) == NULL) {
+	if ((dfname = getpath(dname, libpath, R_OK)) == NULL) {
 		sprintf(errmsg, "cannot find data file \"%s\"", dname);
 		error(USER, errmsg);
 	}
@@ -67,28 +76,55 @@ char  *dname;
 		error(SYSTEM, errmsg);
 	}
 							/* get dimensions */
-	if (fscanf(fp, "%d", &dp->nd) != 1)
+	if (fgetword(word, sizeof(word), fp) == NULL || !isint(word))
 		goto scanerr;
-	if (dp->nd <= 0 || dp->nd > MAXDIM) {
+	dp->nd = atoi(word);
+	if (dp->nd <= 0 || dp->nd > MAXDDIM) {
 		sprintf(errmsg, "bad number of dimensions for \"%s\"", dname);
 		error(USER, errmsg);
 	}
 	asize = 1;
 	for (i = 0; i < dp->nd; i++) {
-		if (fscanf(fp, "%lf %lf %d",
-				&dp->dim[i].org, &dp->dim[i].siz,
-				&dp->dim[i].ne) != 3)
+		if (fgetword(word, sizeof(word), fp) == NULL || !isflt(word))
 			goto scanerr;
-		dp->dim[i].siz -= dp->dim[i].org;
+		dp->dim[i].org = atof(word);
+		if (fgetword(word, sizeof(word), fp) == NULL || !isflt(word))
+			goto scanerr;
+		dp->dim[i].siz = atof(word);
+		if (fgetword(word, sizeof(word), fp) == NULL || !isint(word))
+			goto scanerr;
+		dp->dim[i].ne = atoi(word);
+		if (dp->dim[i].ne < 2)
+			goto scanerr;
 		asize *= dp->dim[i].ne;
+		if ((dp->dim[i].siz -= dp->dim[i].org) == 0) {
+			dp->dim[i].p = (double *)malloc(dp->dim[i].ne*sizeof(double));
+			if (dp->dim[i].p == NULL)
+				goto memerr;
+			for (j = 0; j < dp->dim[i].ne; j++) {
+				if (fgetword(word, sizeof(word), fp) == NULL ||
+						!isflt(word))
+					goto scanerr;
+				dp->dim[i].p[j] = atof(word);
+			}
+			for (j = 1; j < dp->dim[i].ne-1; j++)
+				if ((dp->dim[i].p[j-1] < dp->dim[i].p[j]) !=
+					(dp->dim[i].p[j] < dp->dim[i].p[j+1]))
+					goto scanerr;
+			dp->dim[i].org = dp->dim[i].p[0];
+			dp->dim[i].siz = dp->dim[i].p[dp->dim[i].ne-1]
+						- dp->dim[i].p[0];
+		} else
+			dp->dim[i].p = NULL;
 	}
 	if ((dp->arr = (DATATYPE *)malloc(asize*sizeof(DATATYPE))) == NULL)
 		goto memerr;
 	
-	for (i = 0; i < asize; i++)
-		if (fscanf(fp, DSCANF, &dp->arr[i]) != 1)
+	for (i = 0; i < asize; i++) {
+		if (fgetword(word, sizeof(word), fp) == NULL || !isflt(word))
 			goto scanerr;
-	
+		dp->arr[i] = atof(word);
+	}
 	fclose(fp);
 	dp->next = dlist;
 	return(dlist = dp);
@@ -102,6 +138,17 @@ scanerr:
 }
 
 
+static double  inpaspect;		/* aspect ratio of input picture */
+
+static
+headaspect(s)				/* check string for aspect ratio */
+char  *s;
+{
+	if (isaspect(s))
+		inpaspect *= aspectval(s);
+}
+
+
 DATARRAY *
 getpict(pname)				/* get picture pname */
 char  *pname;
@@ -119,7 +166,7 @@ char  *pname;
 		if (!strcmp(pname, pp->name))
 			return(pp);		/* found! */
 
-	if ((pfname = getpath(pname, libpath)) == NULL) {
+	if ((pfname = getpath(pname, libpath, R_OK)) == NULL) {
 		sprintf(errmsg, "cannot find picture file \"%s\"", pname);
 		error(USER, errmsg);
 	}
@@ -135,22 +182,24 @@ char  *pname;
 		error(SYSTEM, errmsg);
 	}
 						/* get dimensions */
-	getheader(fp, NULL);
-	if (fscanf(fp, "-Y %d +X %d\n", &height, &width) != 2)
+	inpaspect = 1.0;
+	getheader(fp, headaspect);
+	if (fgetresolu(&width, &height, fp) != (YMAJOR|YDECR))
 		goto readerr;
 	for (i = 0; i < 3; i++) {
 		pp[i].nd = 2;
-		pp[i].dim[0].ne = width;
-		pp[i].dim[1].ne = height;
+		pp[i].dim[0].ne = height;
+		pp[i].dim[1].ne = width;
 		pp[i].dim[0].org =
 		pp[i].dim[1].org = 0.0;
-		if (width <= height) {
-			pp[i].dim[0].siz = 1.0;
-			pp[i].dim[1].siz = (double)height/width;
-		} else {
-			pp[i].dim[0].siz = (double)width/height;
+		if (width <= height*inpaspect) {
+			pp[i].dim[0].siz = inpaspect*(double)height/width;
 			pp[i].dim[1].siz = 1.0;
+		} else {
+			pp[i].dim[0].siz = 1.0;
+			pp[i].dim[1].siz = (double)width/height/inpaspect;
 		}
+		pp[i].dim[0].p = pp[i].dim[1].p = NULL;
 		pp[i].arr = (DATATYPE *)malloc(width*height*sizeof(DATATYPE));
 		if (pp[i].arr == NULL)
 			goto memerr;
@@ -163,7 +212,7 @@ char  *pname;
 			goto readerr;
 		for (x = 0; x < width; x++)
 			for (i = 0; i < 3; i++)
-				pp[i].arr[x*height+y] = colval(scanin[x],i);
+				pp[i].arr[y*width+x] = colval(scanin[x],i);
 	}
 	free((char *)scanin);
 	fclose(fp);
@@ -184,6 +233,7 @@ freedata(dname)			/* free memory associated with dname
 char  *dname;
 {
 	register DATARRAY  *dp, *dpl;
+	register int  i;
 
 	for (dpl = NULL, dp = dlist; dp != NULL; dpl = dp, dp = dp->next)
 		if (!strcmp(dname, dp->name)) {
@@ -192,6 +242,9 @@ char  *dname;
 			else
 				dpl->next = dp->next;
 			free((char *)dp->arr);
+			for (i = 0; i < dp->nd; i++)
+				if (dp->dim[i].p != NULL)
+					free((char *)dp->dim[i].p);
 			freestr(dp->name);
 			free((char *)dp);
 			return;
@@ -227,27 +280,48 @@ double  *pt;
 {
 	DATARRAY  sd;
 	int  asize;
+	int  lower, upper;
 	register int  i;
 	double  x, y, y0, y1;
-
+					/* set up dimensions for recursion */
 	sd.nd = dp->nd - 1;
 	asize = 1;
 	for (i = 0; i < sd.nd; i++) {
 		sd.dim[i].org = dp->dim[i+1].org;
 		sd.dim[i].siz = dp->dim[i+1].siz;
+		sd.dim[i].p = dp->dim[i+1].p;
 		asize *= sd.dim[i].ne = dp->dim[i+1].ne;
 	}
-
-	x = (pt[0] - dp->dim[0].org)/dp->dim[0].siz;
-
-	x *= dp->dim[0].ne - 1;
-
-	i = x;
-	if (i < 0)
-		i = 0;
-	else if (i > dp->dim[0].ne - 2)
-		i = dp->dim[0].ne - 2;
-
+					/* get independent variable */
+	if (dp->dim[0].p == NULL) {		/* evenly spaced points */
+		x = (pt[0] - dp->dim[0].org)/dp->dim[0].siz;
+		x = x * (dp->dim[0].ne - 1);
+		i = x;
+		if (i < 0)
+			i = 0;
+		else if (i > dp->dim[0].ne - 2)
+			i = dp->dim[0].ne - 2;
+	} else {				/* unevenly spaced points */
+		if (dp->dim[0].siz > 0.0) {
+			lower = 0;
+			upper = dp->dim[0].ne;
+		} else {
+			lower = dp->dim[0].ne;
+			upper = 0;
+		}
+		do {
+			i = (lower + upper) >> 1;
+			if (pt[0] >= dp->dim[0].p[i])
+				lower = i;
+			else
+				upper = i;
+		} while (i != (lower + upper) >> 1);
+		if (i > dp->dim[0].ne - 2)
+			i = dp->dim[0].ne - 2;
+		x = i + (pt[0] - dp->dim[0].p[i]) /
+				(dp->dim[0].p[i+1] - dp->dim[0].p[i]);
+	}
+					/* get dependent variable */
 	if (dp->nd == 1) {
 		y0 = dp->arr[i];
 		y1 = dp->arr[i+1];
@@ -257,7 +331,6 @@ double  *pt;
 		sd.arr = &dp->arr[(i+1)*asize];
 		y1 = datavalue(&sd, pt+1);
 	}
-
 	/*
 	 * Extrapolate as far as one division, then
 	 * taper off harmonically to zero.