[ViewVC] Diff of: radiance/src/cv/mgflib/mgfdoc.tr

Comparing src/cv/mgflib/mgfdoc.tr (file contents):
Revision 1.1 by greg, Fri May 12 14:26:12 1995 UTC vs.
Revision 1.20 by greg, Fri Feb 28 20:11:29 2003 UTC

#	Line 1 \| Line 1
1	<	.\" SCCSid "$SunId$ LBL"
1	>	.\" RCSid "$Id$"
2		.nr PS 11
3		.ps 11
4		.nr VS 12
5		.vs 12
6		.nr PD .5v
7		.ds LF MGF
8	<	.ds RF Version 1.0
9	<	.DA May 1995
8	>	.ds RF Version 1.1
9	>	.\" !Remember to update date on each modification!
10	>	.DA February 1996
11		.TL
12		The Materials and Geometry Format
13		.AU
#	Line 42 \| Line 43 \| and sample scenes and objects at the web site,
43		"http://radsite.lbl.gov/mgf/HOME.html".
44		.RE
45		.LP
46	<	The standard parser provides both immediate and a long-term
46	>	The standard parser provides both immediate and long-term
47		benefits, since it presents a programming interface that is more
48		stable even than the language itself.
49		Unlike AutoCAD DXF and other de facto standards, a change to the
#	Line 232 \| Line 233 \| p x y z set point position for current vertex
233		n dx dy dz set surface normal for current vertex
234		_ _ _
235		f v1 v2 v3 ... polygon using current material, spec. vertices
236	+	fh v1 v2 v3 - ... face with explicit holes
237		sph vc radius sphere
238		cyl v1 radius v2 truncated right cylinder (open-ended)
239		cone v1 rad1 v2 rad2 truncated right cone (open-ended)
#	Line 277 \| Line 279 \| Context Cntl. Entity Default Value Field Entities Affe
279		= = = = =
280		Object o - - -
281		Transform xf - - T{
282	<	f, sph, cyl, cone,
282	>	f, fh, sph, cyl, cone,
283		ring, torus, prism
284		T}
285		Material m 2-sided black T{
286		sides, rd, td,
287	<	ed, rs, ts
287	>	ed, rs, ts, ir
288		T} T{
289	<	f, sph, cyl, cone,
289	>	f, fh, sph, cyl, cone,
290		ring, torus, prism
291		T}
292		Color c neutral grey T{
#	Line 296 \| Line 298 \| Vertex v T{
298		(0,0,0),
299		no normal
300		T} p, n T{
301	<	f, sph, cyl, cone,
301	>	f, fh, sph, cyl, cone,
302		ring, torus, prism
303		T}
304		.TE
#	Line 431 \| Line 433 \| Since the arguments are concise and self-explanatory,
433		sufficient.
434		The following transformation flags and
435		parameters are defined:
436	<	.TS I
436	>	.TS
437	>	center;
438		l l.
439		-t dx dy dz translate objects along the given vector
440		-rx degrees rotate objects about the X-axis
#	Line 546 \| Line 549 \| Detailed MGF Example
549		The following example of a simple room with a single door
550		and six file cabinets shows MGF in action, with copious comments to
551		help explain what's going on.
552	+	.LP
553		.DS
554		# "ceiling_tile" is a diffuse white surface with 75% reflectance:
555		# Create new named material context and clear it
#	Line 744 \| Line 748 \| o door
748		o
749		o
750
747	–	i cubfurn.inc -mx -t 405 133.5 0
748	–	o
749	–
751		# Six file cabinets (36" wide each)
752		# ("filecab.inc" was given as an earlier example in Section 1.2)
753		o filecab.x
#	Line 772 \| Line 773 \| There are currently 28 entities in the MGF specificati
773		For ease of reference we have broken these into five categories:
774		.IP 1.
775		General
776	<	.TS I
776	>	.TS
777		lw(.75i) lw(1.75i) lw(3i).
778		# [anything ...] a comment
779		o [name] begin/end object context
#	Line 782 \| Line 783 \| ies pathname [-m f][xform] include IES luminaire (with
783		.TE
784		.IP 2.
785		Color
786	<	.TS I
786	>	.TS
787		lw(.75i) lw(1.75i) lw(3i).
788		c [id [= [template]]] get/set color context
789		cxy x y set CIE (x,y) chromaticity for current color
#	Line 816 \| Line 817 \| Geometry
817		.TS
818		lw(.75i) lw(1.75i) lw(3i).
819		f v1 v2 v3 ... polygon using current material, spec. vertices
820	+	fh v1 v2 v3 - ... face with explicit holes
821		sph vc radius sphere
822		cyl v1 radius v2 truncated right cylinder (open-ended)
823		cone v1 rad1 v2 rad2 truncated right cone (open-ended)
#	Line 1267 \| Line 1269 \| corresponds to the measurement at
1269		Values in between are separated by
1270		.I "(l_max-l_min)/(N-1)"
1271		nanometers.
1272	<	All values must be non-negative, and the spectrum outside of the
1272	>	All values should be non-negative unless defining a component for
1273	>	complementary color mixing, and the spectrum outside of the
1274		specified range is assumed to be zero.
1275		(The visible range is 380 to 780 nm.)\0
1276		The actual units and scale of the measurements do not matter,
#	Line 1674 \| Line 1677 \| EXAMPLE
1677		# A 100-watt incandescent bulb (1600 lumens) modeled as a sphere
1678		m
1679		c
1680	<	cct 3000
1680	>	cct 3000
1681		ed 87712
1682		v cent =
1683		p 0 0 0
#	Line 1900 \| Line 1903 \| and
1903		require a normal direction.
1904		An
1905		.UL f
1906	+	or
1907	+	.UL fh
1908		entity will interpolate vertex normals if given, and
1909		use the polygon plane normal otherwise.
1910		See the
#	Line 1939 \| Line 1944 \| SEE ALSO
1944		.UL cone,
1945		.UL cyl,
1946		.UL f,
1947	+	.UL fh,
1948		.UL n,
1949		.UL p,
1950		.UL prism,
#	Line 1983 \| Line 1989 \| SEE ALSO
1989		.UL cone,
1990		.UL cyl,
1991		.UL f,
1992	+	.UL fh,
1993		.UL n,
1994		.UL prism,
1995		.UL ring,
#	Line 2029 \| Line 2036 \| xf
2036		SEE ALSO
2037		.LP
2038		.UL f,
2039	+	.UL fh,
2040		.UL p,
2041		.UL prism,
2042		.UL ring,
#	Line 2068 \| Line 2076 \| when normals are used.
2076		Also, specified normals should point in the general direction of the
2077		surface for best results.
2078		.LP
2079	<	There is no explicit representation of holes in MGF. A hole must be
2080	<	represented implicitly by connecting vertices to form "seams." For
2079	>	There is no explicit representation of holes in this entity, but see
2080	>	the
2081	>	.UL fh
2082	>	entity for an alternative specification.
2083	>	.LP
2084	>	A hole may be represented implicitly in a face entity
2085	>	by connecting vertices to form "seams."
2086	>	For
2087		example, a wall with a window in it might look as shown in Figure 1.
2088		In many systems, the wall itself would be represented with the first
2089		list of vertices, (v1,v2,v3,v4) and the hole associated with that
2090	<	wall as a second set of vertices (v5,v6,v7,v8). In MGF, we must
2090	>	wall as a second set of vertices (v5,v6,v7,v8).
2091	>	Using the face entity, we must
2092		give the whole thing as a single polygon, connecting the vertices so
2093		as to create a "seam," as shown in Figure 2.
2094	<	This could be written in MGF as "f v1 v2 v3 v4 v5 v6 v7 v8 v5 v4".
2094	>	This could be written as "f v1 v2 v3 v4 v5 v6 v7 v8 v5 v4".
2095		.LP
2096		It is very important that the order of the hole be opposite to the
2097		order of the outer perimeter, otherwise the polygon will be
#	Line 2125 \| Line 2140 \| SEE ALSO
2140		.LP
2141		.UL cone,
2142		.UL cyl,
2143	+	.UL fh,
2144		.UL m,
2145		.UL prism,
2146		.UL ring,
2147		.UL sph,
2148		.UL torus,
2149		.UL v
2150	+	.ds RH FH
2151	+	.bp
2152	+	.SH
2153	+	NAME
2154	+	.LP
2155	+	fh - create a polygonal face with explicit holes
2156	+	.SH
2157	+	SYNOPSIS
2158	+	.LP
2159	+	.B fh
2160	+	.I "p1 p2 ... - h1.1 h1.2 ... - h2.1 h2.2 ..."
2161	+	.SH
2162	+	DESCRIPTION
2163	+	.LP
2164	+	Create a polygonal face with optional holes made of the current material.
2165	+	The first contour is the outer perimeter, with vertices given in
2166	+	counter-clockwise order as seen from the front side (the same as the
2167	+	.UL f
2168	+	entity).
2169	+	A hole is indicated by a hyphen ('-') followed by the hole's
2170	+	vertices, given in clockwise order as seen from the front side.
2171	+	Multiple hole contours are separated by additional hyphens.
2172	+	There must be at least three vertices for each contour, and the
2173	+	last vertex is implicitly connected to the first.
2174	+	If any vertex is undefined, an error will result.
2175	+	.LP
2176	+	If any vertices have associated surface normals, they will be used
2177	+	instead of the average plane normal, though it is safest to specify
2178	+	either all normals or no normals, and to stick with triangles
2179	+	when normals are used.
2180	+	Also, specified normals should point in the general direction of the
2181	+	surface for best results.
2182	+	.LP
2183	+	Vertices should not be shared between any two contours.
2184	+	I.e., a hole should not share a vertex or edge with the perimeter or
2185	+	another hole, or incorrect rendering may result.
2186	+	.SH
2187	+	EXAMPLE
2188	+	.DS
2189	+	# Make a wall with a window using an explicit hole.
2190	+	# (See Figures 1 and 2.)
2191	+	fh v1 v2 v3 v4 - v5 v6 v7 v8
2192	+	.DE
2193	+	.SH
2194	+	SEE ALSO
2195	+	.LP
2196	+	.UL cone,
2197	+	.UL cyl,
2198	+	.UL f,
2199	+	.UL m,
2200	+	.UL prism,
2201	+	.UL ring,
2202	+	.UL sph,
2203	+	.UL torus,
2204	+	.UL v
2205		.ds RH SPH
2206		.bp
2207		.SH
#	Line 2179 \| Line 2250 \| SEE ALSO
2250		.UL cone,
2251		.UL cyl,
2252		.UL f,
2253	+	.UL fh,
2254		.UL m,
2255		.UL prism,
2256		.UL ring,
#	Line 2226 \| Line 2298 \| o stylus
2298		p 0 0 .005
2299		v vend =
2300		p 0 0 .05
2301	<	cyl vtip1 .0015
2301	>	cyl vtip1 .0015 vend
2302		sph vend .0015
2303		cone vtip0 0 vtip1 .0015
2304		o
#	Line 2236 \| Line 2308 \| SEE ALSO
2308		.LP
2309		.UL cone,
2310		.UL f,
2311	+	.UL fh,
2312		.UL m,
2313		.UL prism,
2314		.UL ring,
#	Line 2308 \| Line 2381 \| SEE ALSO
2381		.LP
2382		.UL cyl,
2383		.UL f,
2384	+	.UL fh,
2385		.UL m,
2386		.UL prism,
2387		.UL ring,
#	Line 2374 \| Line 2448 \| SEE ALSO
2448		.UL cyl,
2449		.UL cone,
2450		.UL f,
2451	+	.UL fh,
2452		.UL m,
2453		.UL ring,
2454		.UL sph,
#	Line 2388 \| Line 2463 \| ring - create a circular ring with inner and outer rad
2463		.SH
2464		SYNOPSIS
2465		.LP
2466	<	.B cyl
2466	>	.B ring
2467		.I "vc rmin rmax"
2468		.SH
2469		DESCRIPTION
#	Line 2430 \| Line 2505 \| SEE ALSO
2505		.UL cyl,
2506		.UL cone,
2507		.UL f,
2508	+	.UL fh,
2509		.UL m,
2510		.UL prism,
2511		.UL sph,
#	Line 2490 \| Line 2566 \| SEE ALSO
2566		.UL cyl,
2567		.UL cone,
2568		.UL f,
2569	+	.UL fh,
2570		.UL m,
2571		.UL prism,
2572		.UL ring,
#	Line 2501 \| Line 2578 \| SEE ALSO
2578		.NH
2579		MGF Translators
2580		.LP
2581	<	Initially, there are four translators for MGF data, but only
2582	<	one of these is distributed with the MGF parser itself,
2583	<	.I mgfilt.
2581	>	Initially, there are six translators for MGF data, and
2582	>	three of these are distributed with the MGF parser itself,
2583	>	.I mgfilt,
2584	>	.I mgf2inv
2585	>	and
2586	>	.I 3ds2mgf.
2587		Two of the other translators,
2588		.I mgf2rad
2589		and
#	Line 2516 \| Line 2596 \| package\(dg.
2596		nestor.epfl.ch, or by WWW from
2597		"http://radsite.lbl.gov/radiance/HOME.html"
2598		.FE
2599	<	A third translator,
2599	>	The sixth translator,
2600		.I mgf2meta,
2601		converts to a 2-dimensional line plot, and is also
2602		distributed with Radiance.
#	Line 2533 \| Line 2613 \| unwanted entities.
2613		In future releases of MGF, this utility will also be handy for
2614		taking new entities and producing older versions of MGF for
2615		translators that have not yet been updated properly.
2616	+	.LP
2617	+	Mgf2inv converts from MGF to Inventor or VRML format.
2618	+	Some information is lost, because these formats do not support
2619	+	physical light sources or materials.
2620	+	.LP
2621	+	3ds2mgf converts from 3D Studio binary format to MGF.
2622	+	Care must be taken to correct for errors in the material descriptions,
2623	+	since 3D Studio is completely non-physical.
2624		.ds LH Translators
2625		.ds RH MGFILT
2626		.bp
#	Line 2567 \| Line 2655 \| In the first form, a single integer is given for the
2655		of MGF that is to be produced.
2656		Since MGF is in its first major release, this is not yet a useful
2657		form, but it will be when the second major release comes out.
2658	+	This has the necessary side-effect of expanding all included files.
2659	+	(See the
2660	+	.UL i
2661	+	entity.)\0
2662		.LP
2663		In the second form,
2664		.I mgfilt
#	Line 2591 \| Line 2683 \| mgfilt f,v,p,xf input.mgf > flatpoly.mgf
2683		.SH
2684		SEE ALSO
2685		.LP
2686	<	mgf2rad, rad2mgf
2686	>	i, mgf2inv, mgf2rad, rad2mgf
2687	>	.ds RH MGF2INV
2688	>	.bp
2689	>	.SH
2690	>	NAME
2691	>	.LP
2692	>	mgf2inv - convert from MGF to Inventor or VRML format
2693	>	.SH
2694	>	SYNOPSIS
2695	>	.LP
2696	>	.B mgf2inv
2697	>	[
2698	>	.B "-1\|-2\|-vrml"
2699	>	]
2700	>	[
2701	>	.B input ..
2702	>	]
2703	>	.SH
2704	>	DESCRIPTION
2705	>	.LP
2706	>	.I Mgf2inv
2707	>	takes one or more MGF input files and converts it to
2708	>	Inventor or VRML format.
2709	>	If the
2710	>	.I \-1
2711	>	option is used, then Inventor 1.0 ASCII output is produced.
2712	>	If the
2713	>	.I \-2
2714	>	option is used, then Inventor 2.0 ASCII output is produced.
2715	>	(This is the default.)\0
2716	>	If the
2717	>	.I \-vrml
2718	>	option is used, then VRML 1.0 ASCII output is produced.
2719	>	.LP
2720	>	This converter does not work properly for light sources, since
2721	>	the output formats do not support IES-type luminaires with recorded
2722	>	distributions.
2723	>	Also, some material information may be lost because Inventor lacks
2724	>	a physically valid reflectance model.
2725	>	.SH
2726	>	EXAMPLES
2727	>	.LP
2728	>	To take an MGF file and convert it to VRML format:
2729	>	.IP
2730	>	mgf2inv -vrml myscene.mgf > myscene.iv
2731	>	.SH
2732	>	SEE ALSO
2733	>	.LP
2734	>	mgf2rad(1), mgfilt(1), 3ds2mgf(1), rad2mgf(1)
2735	>	.ds RH 3DS2MGF
2736	>	.bp
2737	>	.SH
2738	>	NAME
2739	>	.LP
2740	>	3ds2mgf - convert 3D Studio binary file to Materials and Geometry Format
2741	>	.SH
2742	>	SYNOPSIS
2743	>	.LP
2744	>	.B 3ds2mgf
2745	>	.B input
2746	>	[
2747	>	.B output
2748	>	]
2749	>	[
2750	>	.B -lMatlib
2751	>	][
2752	>	.B -xObjname
2753	>	][
2754	>	.B -sAngle
2755	>	][
2756	>	.B -aAnimfile
2757	>	][
2758	>	.B -fN
2759	>	]
2760	>	.SH
2761	>	DESCRIPTION
2762	>	.LP
2763	>	.I 3ds2mgf
2764	>	converts a 3D Studio binary scene description
2765	>	to the Materials and Geometry Format (MGF).
2766	>	If no output file name is given, the input root name
2767	>	will be taken as the output root, and an "mgf" extension
2768	>	will be added.
2769	>	This file will contain any light sources and materials, and an include
2770	>	statement for a similarly named file ending in "inc", which will contain
2771	>	the MGF geometry of all the translated 3DS meshes.
2772	>	.LP
2773	>	The MGF material names and properties
2774	>	for the surfaces will be those assigned in 3D Studio,
2775	>	unless they are named in one or more MGF material libraries given in a
2776	>	.I -l
2777	>	option.
2778	>	.LP
2779	>	The
2780	>	.I -x
2781	>	option may be used to exclude a named object from the output.
2782	>	.LP
2783	>	The
2784	>	.I -s
2785	>	option may be used to adjust automatic mesh smoothing such that adjacent
2786	>	triangle faces with less than the given angle between them (in degrees)
2787	>	will be smoothed.
2788	>	A value of zero turns smoothing off.
2789	>	The default value is 60 degrees.
2790	>	.LP
2791	>	The
2792	>	.I -a
2793	>	option may be used to specify a 3D Studio animation file, and together with the
2794	>	.I -f
2795	>	option,
2796	>	.I 3ds2mgf
2797	>	will generate a scene description for the specified frame.
2798	>	.LP
2799	>	Note that there are no spaces between the options and their arguments.
2800	>	.SH
2801	>	LIMITATIONS
2802	>	.LP
2803	>	Obviously, since 3D Studio has no notion of physical materials, the
2804	>	translation to MGF material descriptions is very ad hoc, and it will
2805	>	usually be necessary to edit the materials and light sources in
2806	>	the output file or replace materials with proper entries from a material
2807	>	library using the
2808	>	.I -l
2809	>	option.
2810	>	.LP
2811	>	With smoothing turned on (i.e., a non-zero value for the
2812	>	.I -s
2813	>	option), vertices in the MGF output will not be linked in a proper
2814	>	mesh for each object.
2815	>	This is due to the way the automatic smoothing code was originally
2816	>	written, and is too difficult to repair.
2817	>	If a good mesh is needed, then smoothing must be turned off.
2818	>	.SH
2819	>	EXAMPLES
2820	>	.LP
2821	>	To convert a 3D Studio robot model to MGF without smoothing.
2822	>	(Output will be put into "robot.mgf" and "robot.inc".)
2823	>	.IP
2824	>	3ds2mgf robot.3ds -s0
2825	>	.LP
2826	>	To convert a DC10 jet model to MGF using a hand-created material library:
2827	>	.IP
2828	>	3ds2mgf dc10.3ds -ldc10mat.mgf
2829	>	.SH
2830	>	AUTHORS
2831	>	.LP
2832	>	Steve Anger, Jeff Bowermaster and Greg Ward
2833	>	.br
2834	>	Extended from 3ds2pov 1.8.
2835	>	.SH
2836	>	SEE ALSO
2837	>	.LP
2838	>	mgf2inv(1), mgf2meta(1), mgf2rad(1)
2839		.ds RH MGF2RAD
2840		.bp
2841		.SH
#	Line 2695 \| Line 2939 \| Greg Ward
2939		SEE ALSO
2940		.LP
2941		ies2rad(1), mgf2meta(1), obj2rad(1), oconv(1), rad2mgf(1), xform(1)
2942	<	.ds RH
2699	<	RAD2MGF
2942	>	.ds RH RAD2MGF
2943		.bp
2944		.SH
2945		NAME
#	Line 2985 \| Line 3228 \| char av;**
3228
3229		if (ac < 4) /* check # arguments */
3230		return(MG_EARGC);
3231	<	printf("face\n"); /* begin face output */
3231	>	printf("face\\\\n"); /* begin face output */
3232		for (i = 1; i < ac; i++) {
3233		if ((vp = c_getvert(av[i])) == NULL) /* vertex from name */
3234		return(MG_EUNDEF);
3235		xf_xfmpoint(vert, vp->p); /* apply transform */
3236	<	printf("%15.9f %15.9f %15.9f\n",
3236	>	printf("%15.9f %15.9f %15.9f\\\\n",
3237		vert[0], vert[1], vert[2]); /* output vertex */
3238		}
3239	<	printf(";\\n"); /* end of face output */
3239	>	printf(";\\\\n"); /* end of face output */
3240		return(MG_OK); /* normal exit */
3241		}
3242
#	Line 3122 \| Line 3365 \| following:
3365		#define MG_E_CMIX 4 /* cmix */
3366		#define MG_E_CSPEC 5 /* cspec */
3367		#define MG_E_CXY 6 /* cxy */
3368	<	#define MG_E_CYL 7 /* cyl */
3368	>	#define MG_E_CYL 7 /* cyl */
3369		#define MG_E_ED 8 /* ed */
3370		#define MG_E_FACE 9 /* f */
3371		#define MG_E_INCLUDE 10 /* i */
3372		#define MG_E_IES 11 /* ies */
3373	<	#define MG_E_IR 12 /* ir */
3373	>	#define MG_E_IR 12 /* ir */
3374		#define MG_E_MATERIAL 13 /* m */
3375		#define MG_E_NORMAL 14 /* n */
3376		#define MG_E_OBJECT 15 /* o */
#	Line 3267 \| Line 3510 \| and return one of the non-zero values from "parser.h"
3510		#define MG_EUNK 1 /* unknown entity */
3511		#define MG_EARGC 2 /* wrong number of arguments */
3512		#define MG_ETYPE 3 /* argument type error */
3513	<	#define MG_EILL 4 /* illegal argument value */
3513	>	#define MG_EILL 4 /* illegal argument value */
3514		#define MG_EUNDEF 5 /* undefined reference */
3515		#define MG_ENOFILE 6 /* cannot open input file */
3516		#define MG_EINCL 7 /* error in included file */
3517		#define MG_EMEM 8 /* out of memory */
3518		#define MG_ESEEK 9 /* file seek error */
3519		#define MG_EBADMAT 10 /* bad material specification */
3520	+	#define MG_ELINE 11 /* input line too long */
3521	+	#define MG_ECNTXT 12 /* unmatched context close */
3522
3523	<	#define MG_NERRS 11
3523	>	#define MG_NERRS 13
3524		.DE
3525		If it is inappropriate to send output to standard error, the calling
3526		program should use the routines listed under
#	Line 3289 \| Line 3534 \| listed above in the native country's language.
3534		.SH
3535		SEE ALSO
3536		.LP
3537	<	mg_fgetpos, mg_handle, mg_init
3537	>	mg_fgetpos, mg_handle, mg_init, mg_open
3538		.ds RH MG_OPEN
3539		.bp
3540		.SH
#	Line 3359 \| Line 3604 \| The
3604		function reads the next input line from the current file,
3605		returning the number of characters in the line, or zero if the
3606		end of file is reached or there is a file error.
3607	<	The function skips over escaped newlines, and keeps track of the
3607	>	If the value returned equals MG_MAXLINE-1,
3608	>	then the input line was too long, and you
3609	>	should return an MG_ELINE error.
3610	>	The function keeps track of the
3611		line number in the current file context
3612		.I mg_file,
3613		which also contains the line that was read.
#	Line 3679 \| Line 3927 \| *typedef FLOAT FVECT[3]; / a 3-d real vector /*
3927
3928		typedef struct {
3929		int clock; /* incremented each change -- resettable */
3930	+	char client_data; / pointer to private client data */
3931		FVECT p, n; /* point and normal */
3932		} C_VERTEX; /* vertex context */
3933		.DE
#	Line 3695 \| Line 3944 \| To link identical vertices, one must also check that t
3944		transform has not changed, which is uniquely identified by the
3945		global
3946		.I xf_context->xid
3947	<	variable, but only if one is using the parser libraries transform
3947	>	variable, but only if one is using the parser library's transform
3948		handler.
3949		(See the
3950		.I xf_handler
3951		page.)\0
3952	+	The
3953	+	.I client_data
3954	+	pointer may be used to index private application data for vertex
3955	+	linking, etc.
3956	+	This pointer is initialized to NULL when the context is created,
3957	+	and otherwise ignored by the parser library.
3958		.LP
3959	<	It is possible but not recommended to alter the contents of the
3959	>	It is possible but not recommended to alter the shared contents of the
3960		vertex structure returned by
3961		.I c_getvert.
3962		Normally it is read during the
#	Line 3822 \| Line 4077 \| structure, defined in "parser.h" as:
4077
4078		typedef struct {
4079		int clock; /* incremented each change */
4080	+	char client_data; / pointer to private client data */
4081		short flags; /* what's been set */
4082		short ssamp[C_CNSS]; /* spectral samples, min wl to max */
4083		long ssum; /* straight sum of spectral values */
#	Line 3837 \| Line 4093 \| desired.
4093		This is a convenient way to keep track of whether or not a color has
4094		changed since its last use.
4095		The
4096	+	.I client_data
4097	+	pointer may be used to index private application data.
4098	+	This pointer is initialized to NULL when the context is created,
4099	+	and otherwise ignored by the parser library.
4100	+	The
4101		.I flags
4102		member indicates which color representations have been assigned,
4103		and is an inclusive OR of one or more of the following:
#	Line 3981 \| Line 4242 \| structure, defined in "parser.h" as:
4242
4243		typedef struct {
4244		int clock; /* incremented each change -- resettable */
4245	+	char client_data; / pointer to private client data */
4246		int sided; /* 1 if surface is 1-sided, 0 for 2-sided */
4247		float nr, ni; /* index of refraction, real and imaginary */
4248		float rd; /* diffuse reflectance */
#	Line 4004 \| Line 4266 \| material field entity, and may be reset by the calling
4266		desired.
4267		This is a convenient way to keep track of whether or not a material has
4268		changed since its last use.
4269	+	The
4270	+	.I client_data
4271	+	pointer may be used to index private application data.
4272	+	This pointer is initialized to NULL when the context is created,
4273	+	and otherwise ignored by the parser library.
4274		.LP
4275		All reflectance and transmittance values correspond to normal
4276		incidence, and may vary as a function of angle depending on the
#	Line 4275 \| Line 4542 \| mg_init, mg_load, obj_handler, xf_xfmpoint
4542		.SH
4543		NAME
4544		.LP
4545	<	xf_xfmpoint xf_xfmvect, xf_rotvect, xf_scale - apply current
4545	>	xf_xfmpoint, xf_xfmvect, xf_rotvect, xf_scale - apply current
4546		transformation
4547		.SH
4548		SYNOPSIS
#	Line 4304 \| Line 4571 \| to the point
4571		.I pold,
4572		scaling, rotating and moving it to its proper location, which is put in
4573		.I pnew.
4574	<	(The two arguments may point to the same vector.)\0
4574	>	(As for
4575	>	.I xf_xfmvect
4576	>	and
4577	>	.I xf_rotvect,
4578	>	the two arguments may point to the same vector.)\0
4579		.LP
4580		The
4581		.I xf_xfmvect
#	Line 4312 \| Line 4583 \| routine applies the current transformation to the vect
4583		.I vold,
4584		scaling and rotating it to its proper location, which is put in
4585		.I vnew.
4315	–	(The two arguments may point to the same vector.)\0
4586		The only difference between
4587		.I xf_xfmpoint
4588		and
#	Line 4325 \| Line 4595 \| routine rotates the vector
4595		.I nold
4596		using the current transformation, and stores the result in
4597		.I nnew.
4328	–	(The two arguments may point to the same vector.)\0
4598		No translation or scaling is applied, which is the appropriate
4599		action for surface normal vectors for example.
4600		.LP
#	Line 4424 \| Line 4693 \| familiar Gaussian model of MGF.
4693		The hardest part is translating the specular power to a roughness value.
4694		For this, we recommend the following approximation:
4695		.IP
4696	<	roughness = 0.6/sqrt(specular_power)
4696	>	roughness = sqrt(2/specular_power)
4697		.LP
4698		It is not a perfect correlation, but it is about as close as one can get.
4699		.NH 3
#	Line 4486 \| Line 4755 \| and adopt the following code to convert between CIE an
4755		#define CIE_y_w 0.3333
4756		#endif
4757
4758	<	#define CIE_D ( CIE_x_r*(CIE_y_g - CIE_y_b) + \\\\
4759	<	CIE_x_g*(CIE_y_b - CIE_y_r) + \\\\
4758	>	#define CIE_D ( CIE_x_r*(CIE_y_g - CIE_y_b) + \\
4759	>	CIE_x_g*(CIE_y_b - CIE_y_r) + \\
4760		CIE_x_b*(CIE_y_r - CIE_y_g) )
4761	<	#define CIE_C_rD ( (1./CIE_y_w) * \\\\
4762	<	( CIE_x_w*(CIE_y_g - CIE_y_b) - \\\\
4763	<	CIE_y_w*(CIE_x_g - CIE_x_b) + \\\\
4761	>	#define CIE_C_rD ( (1./CIE_y_w) * \\
4762	>	( CIE_x_w*(CIE_y_g - CIE_y_b) - \\
4763	>	CIE_y_w*(CIE_x_g - CIE_x_b) + \\
4764		CIE_x_gCIE_y_b - CIE_x_bCIE_y_g ) )
4765	<	#define CIE_C_gD ( (1./CIE_y_w) * \\\\
4766	<	( CIE_x_w*(CIE_y_b - CIE_y_r) - \\\\
4767	<	CIE_y_w*(CIE_x_b - CIE_x_r) - \\\\
4765	>	#define CIE_C_gD ( (1./CIE_y_w) * \\
4766	>	( CIE_x_w*(CIE_y_b - CIE_y_r) - \\
4767	>	CIE_y_w*(CIE_x_b - CIE_x_r) - \\
4768		CIE_x_rCIE_y_b + CIE_x_bCIE_y_r ) )
4769	<	#define CIE_C_bD ( (1./CIE_y_w) * \\\\
4770	<	( CIE_x_w*(CIE_y_r - CIE_y_g) - \\\\
4771	<	CIE_y_w*(CIE_x_r - CIE_x_g) + \\\\
4769	>	#define CIE_C_bD ( (1./CIE_y_w) * \\
4770	>	( CIE_x_w*(CIE_y_r - CIE_y_g) - \\
4771	>	CIE_y_w*(CIE_x_r - CIE_x_g) + \\
4772		CIE_x_rCIE_y_g - CIE_x_gCIE_y_r ) )
4773
4774		#define CIE_rf (CIE_y_r*CIE_C_rD/CIE_D)

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Comparing src/cv/mgflib/mgfdoc.tr (file contents): Revision 1.1 by greg, Fri May 12 14:26:12 1995 UTC vs. Revision 1.20 by greg, Fri Feb 28 20:11:29 2003 UTC

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Comparing src/cv/mgflib/mgfdoc.tr (file contents):
Revision 1.1 by greg, Fri May 12 14:26:12 1995 UTC vs.
Revision 1.20 by greg, Fri Feb 28 20:11:29 2003 UTC