--- ray/src/cv/ies2rad.c	2018/06/04 18:53:09	2.29
+++ ray/src/cv/ies2rad.c	2021/09/30 20:05:09	2.34
@@ -1,5 +1,5 @@
 #ifndef lint
-static const char	RCSid[] = "$Id: ies2rad.c,v 2.29 2018/06/04 18:53:09 greg Exp $";
+static const char	RCSid[] = "$Id: ies2rad.c,v 2.34 2021/09/30 20:05:09 greg Exp $";
 #endif
 /*
  * ies2rad -- Convert IES luminaire data to Radiance description
@@ -20,10 +20,9 @@ static const char	RCSid[] = "$Id: ies2rad.c,v 2.29 201
  * Radiance (θ,φ) luminaire coordinates and then apply photometric and
  * tilt data to generate Radiance light. θ is altitude from the
  * negative z-axis and φ is azimuth from the positive x-axis,
- * increasing towards the positive y-axis. [??? Greg, is there a
- * source for this convention?] This system matches none of the usual
- * goniophotometric conventions, but it is closest to IES type C; V in
- * type C photometry is θ in Radiance and L is -φ.
+ * increasing towards the positive y-axis. This system matches none of
+ * the usual goniophotometric conventions, but it is closest to IES
+ * type C; V in type C photometry is θ in Radiance and L is -φ.
  *
  * The ies2rad scene description for a luminaire LUM, with tilt data,
  * uses the following Radiance scene description primitives:
@@ -70,10 +69,7 @@ static const char	RCSid[] = "$Id: ies2rad.c,v 2.29 201
  *  Extensive comments added by Randolph Fritz May2018
  */
 
-#include <stdio.h>
-#include <string.h>
 #include <math.h>
-#include <sys/types.h>
 #include <ctype.h>
 
 #include "rtio.h"
@@ -92,6 +88,9 @@ static const char	RCSid[] = "$Id: ies2rad.c,v 2.29 201
 /* Since 1991, LM-63 files have begun with the magic keyword IESNA */
 #define MAGICID		"IESNA"
 #define LMAGICID	5
+/* But newer files start with IESNA:LM-63- */
+#define MAGICID2	"IESNA:LM-63-"
+#define LMAGICID2	12
 /* ies2rad supports the 1986, 1991, and 1995 versions of
  * LM-63. FIRSTREV describes the first version; LASTREV describes the
  * 1995 version. */
@@ -204,8 +203,8 @@ int	filerev = FIRSTREV;
 #define U_METERS	2
 
 /* string lengths */
-/* Maximum input line is 132 characters including CR LF at end. */
-#define MAXLINE		133
+/* Maximum input line is 256 characters including CR LF at end. */
+#define MAXLINE		257
 #define RMAXWORD	76
 
 /* End of LM-63-related #defines */
@@ -224,7 +223,7 @@ int	filerev = FIRSTREV;
 #define DISK		2
 #define SPHERE		3
 
-/* The diameter of a point source luminaire model. Also the minimum
+/* 1mm.  The diameter of a point source luminaire model. Also the minimum
  * size (in meters) that the luminous opening of a luminaire must have
  * to be treated as other than a point source. */
 #define MINDIM		.001
@@ -725,6 +724,9 @@ k_match(
 	char	*hdl		/* header line */
 )
 {
+	/* Skip leading spaces */
+	while (isspace(*hdl))
+		hdl++;
 	/* The line has to begin with '[' */
 	if (*hdl++ != '[')
 		return(0);
@@ -840,11 +842,11 @@ ies2rad(		/* convert IES file */
 			continue;
 		/* increment the header line count, and check for the
 		 * "TILT=" line that terminates the header */
-		if (!lineno++ && strncmp(buf, MAGICID, LMAGICID) == 0) {
-			/* This code doesn't work for LM-63-95 and
-			 * LM-63-02 files and will instead default to
-			 * LM-63-86. */
-			filerev = atoi(buf+LMAGICID);
+		if (!lineno++) {	/* first line may be magic */
+			if (!strncmp(buf, MAGICID2, LMAGICID2))
+				filerev = atoi(buf+LMAGICID2) - 1900;
+			else if (!strncmp(buf, MAGICID, LMAGICID))
+				filerev = atoi(buf+LMAGICID);
 			if (filerev < FIRSTREV)
 				filerev = FIRSTREV;
 			else if (filerev > LASTREV)
@@ -860,7 +862,7 @@ ies2rad(		/* convert IES file */
 		 * in the "[LAMP]" and "[LAMPCAT]" keyword lines;
 		 * otherwise check all lines.  */
 		if (lampcolor == NULL && checklamp(buf))
-			lampcolor = matchlamp( buf[0] == '[' ?
+			lampcolor = matchlamp(*sskip2(buf,0) == '[' ?
 						keyargs(buf) : buf );
 		/* Look for a materials and geometry file in the keywords. */
 		if (keymatch(K_LMG, buf)) {
@@ -881,6 +883,7 @@ ies2rad(		/* convert IES file */
 	} else if (lamptype == NULL)
 		fprintf(outfp,"# CIE(x,y) = (%f,%f)\n# Depreciation = %.1f%%\n",
 				lampcolor[3], lampcolor[4], 100.*lampcolor[5]);
+
 	/* If the file ended before a "TILT=" line, that's an error. */
 	if (feof(inpfp)) {
 		fprintf(stderr, "%s: not in IES format\n", inpname);
@@ -965,7 +968,7 @@ dotilt(
 		datin = in;
 		strcpy(tltname, dfltname);
 	} else {
-		/* If the line is "TILE=<filename>", use that file
+		/* If the line is "TILT=<filename>", use that file
 		 * name as the source of tilt data. */
 		if (ISDIRSEP(tltspec[0]))
 			strcpy(buf, tltspec);
@@ -1122,7 +1125,7 @@ dosource(
 	/* Output distribution "brightdata" primitive. Start handling
 	   the various cases of symmetry of the distribution. */
 	strcat(strcpy(id, filename(name)), "_dist");
-	fprintf(out, "\n%s brightdata %s\n", mod, id);
+	fprintf(out, "\n'%s' brightdata '%s'\n", mod, id);
 	if (nangles[1] < 2)
 		fprintf(out, "4 ");
 	else if (pmtype == PM_B)
@@ -1140,7 +1143,7 @@ dosource(
 	dosides = (doupper & dolower && sinf->h > MINDIM); /* Sides */
 
 	/* Select the appropriate function and parameters from source.cal */
-	fprintf(out, "%s %s source.cal ",
+	fprintf(out, "%s '%s' source.cal ",
 			sinf->type==SPHERE ? "corr" :
 			!dosides ? "flatcorr" :
 			sinf->type==DISK ? "cylcorr" : "boxcorr",
@@ -1210,7 +1213,7 @@ putsource(
 	/* First, describe the light. If a materials and geometry
 	 * file is given, generate an illum instead. */
 	strcat(strcpy(lname, name), "_light");
-	fprintf(fp, "\n%s %s %s\n", mod,
+	fprintf(fp, "\n'%s' %s '%s'\n", mod,
 			shp->isillum ? "illum" : "light", lname);
 	fprintf(fp, "0\n0\n3 %g %g %g\n",
 			lampcolor[0], lampcolor[1], lampcolor[2]);
@@ -1246,8 +1249,22 @@ putsource(
 
 /* makeshape -- decide what shape will be used
  *
- * makeshape decides what Radiance geometry will be used to represent
+ * Makeshape decides what Radiance geometry will be used to represent
  * the light source and stores information about it in shp.
+ * 
+ * The various versions of the IES LM-63 standard give a "luminous
+ * opening" (really a crude shape) a width, a length (or depth), and a
+ * height.  If all three values are positive, they describe a box.  If
+ * they are all zero, they describe a point.  Various combinations of
+ * negative values are used to denote disks, circular or elliptical
+ * cylinders, spheres, and ellipsoids.  This encoding differs from
+ * version to version of LM-63.
+ *
+ * Ies2rad simplifies this, reducing the geometry of LM-63 files to
+ * three forms which can be easily represented by Radiance primitives:
+ * boxes (RECT), cylinders or disks (DISK), and spheres (SPHERE.)  A
+ * point is necessarily represented by a small sphere, since a point
+ * is not a Radiance object.
  */
 int
 makeshape(
@@ -1259,24 +1276,28 @@ makeshape(
 {
 	/* Categorize the shape */
 	if (illumrad/meters2out >= MINDIM/2.) {
-		/* If the -i command line option is used, and the
-		 * object is not a point source, output an "illum"
-		 * sphere */
+		/* If the -i command line option is used, output an
+		 * "illum" sphere whose radius is given by the
+		 * argument to -i. */
 		shp->isillum = 1;
 		shp->type = SPHERE;
 		shp->w = shp->l = shp->h = 2.*illumrad / meters2out;
+		/* Otherwise, use the dimensions in the IES file */
 	} else if (width < MINDIM) {
-		/* The width is either zero or negative. */
 		width = -width;
 		if (width < MINDIM) {
-			/* The width is zero. Use a tiny sphere to
-			 * represent a point source. */
+			/* If the LM-63 width is zero, assume a point
+			 * source is described.  Output a small
+			 * sphere. */
 			shp->type = SPHERE;
 			shp->w = shp->l = shp->h = MINDIM;
 		} else if (height < .5*width) {
 			/* The width is negative and the height is
-			 * modest; output either a disk or a thin
-			 * vertical cylinder. */
+			 * less than half the width.  Treat the
+			 * luminous opening as a disk or short
+			 * vertical cylinder. Disks will be
+			 * represented as nearly flat cylinders of
+			 * MINDIM/2 height. */
 			shp->type = DISK;
 			shp->w = shp->l = width;
 			if (height >= MINDIM)
@@ -1284,14 +1305,13 @@ makeshape(
 			else
 				shp->h = .5*MINDIM;
 		} else {
-			/* The width is negative and the object is
-			 * tall; output a sphere. */
+			/* Treat a tall cylinder as a sphere. */
 			shp->type = SPHERE;
 			shp->w = shp->l = shp->h = width;
 		}
 	} else {
-		/* The width is positive. Output a box, possibly very
-		 * thin. */
+		/* The width is positive. The luminous opening is a
+		   box or simple rectangle. */
 		shp->type = RECT;
 		shp->w = width;
 		if (length >= MINDIM)
@@ -1405,7 +1425,7 @@ putrect(
 	int d
 )
 {
-	fprintf(fp, "\n%s polygon %s%s\n0\n0\n12\n", mod, name, suffix);
+	fprintf(fp, "\n'%s' polygon '%s%s'\n0\n0\n12\n", mod, name, suffix);
 	putpoint(shp, fp, a);
 	putpoint(shp, fp, b);
 	putpoint(shp, fp, c);
@@ -1450,13 +1470,13 @@ putdisksrc(		/* put out a disk source */
 )
 {
 	if (up) {
-		fprintf(fp, "\n%s ring %s.u\n", mod, name);
+		fprintf(fp, "\n'%s' ring '%s.u'\n", mod, name);
 		fprintf(fp, "0\n0\n8\n");
 		fprintf(fp, "\t0 0 %g\n", .5*shp->h*meters2out);
 		fprintf(fp, "\t0 0 1\n");
 		fprintf(fp, "\t0 %g\n", .5*shp->w*meters2out);
 	} else {
-		fprintf(fp, "\n%s ring %s.d\n", mod, name);
+		fprintf(fp, "\n'%s' ring '%s.d'\n", mod, name);
 		fprintf(fp, "0\n0\n8\n");
 		fprintf(fp, "\t0 0 %g\n", -.5*shp->h*meters2out);
 		fprintf(fp, "\t0 0 -1\n");
@@ -1473,7 +1493,7 @@ putcyl(			/* put out a cylinder */
 	char	*name
 )
 {
-	fprintf(fp, "\n%s cylinder %s.c\n", mod, name);
+	fprintf(fp, "\n'%s' cylinder '%s.c'\n", mod, name);
 	fprintf(fp, "0\n0\n7\n");
 	fprintf(fp, "\t0 0 %g\n", .5*shp->h*meters2out);
 	fprintf(fp, "\t0 0 %g\n", -.5*shp->h*meters2out);
@@ -1490,7 +1510,7 @@ putspheresrc(		/* put out a sphere source */
 	char	*name
 )
 {
-	fprintf(fp, "\n%s sphere %s.s\n", mod, name);
+	fprintf(fp, "\n'%s' sphere '%s.s'\n", mod, name);
 	fprintf(fp, "0\n0\n4 0 0 0 %g\n", .5*shp->w*meters2out);
 }