src/cv/lampcolor.c

/* Copyright (c) 1991 Regents of the University of California */

#ifndef lint
static char SCCSid[] = "$SunId$ LBL";
#endif

/*
 * Program to convert lamp color from table and compute radiance.
 */

#include <stdio.h>

#include <math.h>

#include "color.h"

#define PI      3.14159265358979323846

extern char     *gets(), *strcpy();
extern float    *matchlamp();

                                /* lamp parameters */
#define LTYPE           0
#define LUNIT           1
#define LGEOM           2
#define LOUTP           3
#define NPARAMS         4

int     typecheck(), unitcheck(), geomcheck(), outpcheck();

float   *lampcolor;             /* the lamp color (RGB) */
double  unit2meter;             /* conversion from units to meters */
double  area;                   /* radiating area for this geometry */
double  lumens;                 /* total lamp lumens */

struct {
        char    *name;
        char    value[64];
        int     (*check)();
        char    *help;
} param[NPARAMS] = {
        { "lamp type", "WHITE", typecheck,
"The lamp type is a string which corresponds to one of the types registered\n\
in the lamp table file.  A value of \"WHITE\" means an uncolored source,\n\
which may be preferable because it results in a color balanced image." },
        { "length unit", "meter", unitcheck,
"Unit must be one of:  \"meter\", \"centimeter\", \"foot\", or \"inch\".\n\
These may be abbreviated as a single letter." },
        { "lamp geometry", "polygon", geomcheck,
"The lamp geometry must be one of:  \"polygon\", \"sphere\", \"cylinder\"\n\
or \"ring\".  These may be abbreviated as a single letter." },
        { "total lamp lumens", "0", outpcheck,
"This is the overall light output of the lamp and its fixture.  If you do\n\
not know this value explicitly, you can compute the approximate lumens\n\
by multiplying the input wattage by 14 for incandescent fixtures or 70\n\
for fluorescent fixtures." },
};


main(argc, argv)
int     argc;
char    *argv[];
{
        char    *lamptab = "lamp.tab";
        char    buf[64];
        int     i;

        if (argc > 1) lamptab = argv[1];
        if (loadlamps(lamptab) == 0) {
                fprintf(stderr, "%s: no such lamp table\n", lamptab);
                exit(1);
        }
        printf("Program to compute lamp radiance.  Enter '?' for help.\n");
        for ( ; ; ) {
                i = 0;
                while (i < NPARAMS) {
                        printf("Enter %s [%s]: ", param[i].name,
                                        param[i].value);
                        if (gets(buf) == NULL)
                                exit(0);
                        if (buf[0] == '?') {
                                puts(param[i].help);
                                continue;
                        }
                        if (buf[0])
                                strcpy(param[i].value, buf);
                        if (!(*param[i].check)(param[i].value)) {
                                fprintf(stderr, "%s: bad value for %s\n",
                                                param[i].value, param[i].name);
                                continue;
                        }
                        i++;
                }
                compute();
        }
}


typecheck(s)                    /* check lamp type */
char    *s;
{
        lampcolor = matchlamp(s);
        return(lampcolor != NULL);
}


unitcheck(s)                    /* compute conversion to meters */
char    *s;
{
        int     len = strlen(s);

        switch (*s) {
        case 'm':
                if (strncmp(s, "meters", len))
                        return(0);
                unit2meter = 1.0;
                return(1);
        case 'c':
                if (strncmp(s, "centimeters", len) && strncmp(s, "cms", len))
                        return(0);
                unit2meter = 0.01;
                return(1);
        case 'f':
                if (strncmp(s, "foot", len) && strncmp(s, "feet", len))
                        return(0);
                unit2meter = 0.3048;
                return(1);
        case 'i':
                if (strncmp(s, "inches", len))
                        return(0);
                unit2meter = 0.0254;
                return(1);
        }
        return(0);
}


geomcheck(s)                    /* check/set lamp geometry */
char    *s;
{
        int     len = strlen(s);

        switch (*s) {
        case 'p':
                if (strncmp(s, "polygonal", len))
                        return(0);
                return(getpolygon());
        case 's':
                if (strncmp(s, "sphere", len) && strncmp(s, "spherical", len))
                        return(0);
                return(getsphere());
        case 'c':
                if (strncmp(s,"cylinder",len) && strncmp(s,"cylindrical",len))
                        return(0);
                return(getcylinder());
        case 'r':
                if (strncmp(s, "ring", len) && strncmp(s, "disk", len))
                        return(0);
                return(getring());
        }
        return(0);
}


outpcheck(s)                    /* check lumen output value */
register char   *s;
{
        if ((*s < '0' || *s > '9') && *s != '.')
                return(0);
        lumens = atof(s);
        return(1);
}


compute()                       /* compute lamp radiance */
{
        double  whiteval;

        whiteval = lumens/area/(WHTEFFICACY*PI);

        printf("Lamp color (RGB) = %f %f %f\n",
                        lampcolor[0]*whiteval,
                        lampcolor[1]*whiteval,
                        lampcolor[2]*whiteval);
}


getd(name, dp, help)            /* get a positive double from stdin */
char    *name;
double  *dp;
char    *help;
{
        char    buf[32];
again:
        printf("%s [%g]: ", name, *dp);
        if (gets(buf) == NULL)
                return(0);
        if (buf[0] == '?') {
                puts(help);
                goto again;
        }
        if ((buf[0] < '0' || buf[0] > '9') && buf[0] != '.')
                return(0);
        *dp = atof(buf);
        return(1);
}


getpolygon()                    /* get projected area for a polygon */
{
        static double   parea = 1.0;

        getd("Polygon area", &parea,
                "Enter the total radiating area of the polygon.");
        area = unit2meter*unit2meter * parea;
        return(1);
}


getsphere()                     /* get projected area for a sphere */
{
        static double   radius = 1.0;

        getd("Sphere radius", &radius,
                "Enter the distance from the sphere's center to its surface.");
        area = 4.*PI*unit2meter*unit2meter * radius*radius;
        return(1);
}


getcylinder()                   /* get projected area for a cylinder */
{
        static double   length = 1.0, radius = 0.1;

        getd("Cylinder length", &length,
                "Enter the length of the cylinder.");
        getd("Cylinder radius", &radius,
                "Enter the distance from the cylinder's axis to its surface.");
        area = 2.*PI*unit2meter*unit2meter * radius*length;
        return(1);
}


getring()                       /* get projected area for a ring */
{
        static double   radius = 1.0;

        getd("Disk radius", &radius,
"Enter the distance from the ring's center to its outer edge.\n\
The inner radius must be zero.");
        area = PI*unit2meter*unit2meter * radius*radius;
        return(1);
}
Revision:	2.5
Committed:	Tue Jul 5 15:49:51 1994 UTC (30 years, 3 months ago) by saba
Content type:	text/plain
Branch:	MAIN
Changes since 2.4:	+2 -2 lines
Log Message:	added WHITE to replace D65WHITE for previous color conversion
#	User	Rev	Content
1	greg	1.1	/* Copyright (c) 1991 Regents of the University of California */
2
3			#ifndef lint
4			static char SCCSid[] = "$SunId$ LBL";
5			#endif
6
7			/*
8	greg	1.2	* Program to convert lamp color from table and compute radiance.
9	greg	1.1	*/
10
11			#include <stdio.h>
12
13	greg	2.4	#include <math.h>
14
15	greg	1.8	#include "color.h"
16
17	greg	1.2	#define PI 3.14159265358979323846
18
19			extern char gets(), strcpy();
20	greg	1.1	extern float *matchlamp();
21
22	greg	1.2	/* lamp parameters */
23			#define LTYPE 0
24			#define LUNIT 1
25			#define LGEOM 2
26			#define LOUTP 3
27			#define NPARAMS 4
28	greg	1.1
29	greg	1.2	int typecheck(), unitcheck(), geomcheck(), outpcheck();
30
31			float lampcolor; / the lamp color (RGB) */
32			double unit2meter; /* conversion from units to meters */
33	greg	1.7	double area; /* radiating area for this geometry */
34	greg	1.2	double lumens; /* total lamp lumens */
35
36			struct {
37			char *name;
38			char value[64];
39			int (*check)();
40			char *help;
41			} param[NPARAMS] = {
42	saba	2.5	{ "lamp type", "WHITE", typecheck,
43	greg	1.2	"The lamp type is a string which corresponds to one of the types registered\n\
44	saba	2.5	in the lamp table file. A value of \"WHITE\" means an uncolored source,\n\
45	greg	1.2	which may be preferable because it results in a color balanced image." },
46			{ "length unit", "meter", unitcheck,
47			"Unit must be one of: \"meter\", \"centimeter\", \"foot\", or \"inch\".\n\
48			These may be abbreviated as a single letter." },
49			{ "lamp geometry", "polygon", geomcheck,
50			"The lamp geometry must be one of: \"polygon\", \"sphere\", \"cylinder\"\n\
51			or \"ring\". These may be abbreviated as a single letter." },
52			{ "total lamp lumens", "0", outpcheck,
53			"This is the overall light output of the lamp and its fixture. If you do\n\
54			not know this value explicitly, you can compute the approximate lumens\n\
55	greg	1.3	by multiplying the input wattage by 14 for incandescent fixtures or 70\n\
56	greg	1.2	for fluorescent fixtures." },
57			};
58
59
60	greg	1.1	main(argc, argv)
61			int argc;
62			char *argv[];
63			{
64			char *lamptab = "lamp.tab";
65	greg	1.2	char buf[64];
66			int i;
67	greg	1.1
68			if (argc > 1) lamptab = argv[1];
69			if (loadlamps(lamptab) == 0) {
70	greg	1.2	fprintf(stderr, "%s: no such lamp table\n", lamptab);
71	greg	1.1	exit(1);
72			}
73	greg	1.2	printf("Program to compute lamp radiance. Enter '?' for help.\n");
74	greg	1.1	for ( ; ; ) {
75	greg	1.2	i = 0;
76			while (i < NPARAMS) {
77			printf("Enter %s [%s]: ", param[i].name,
78			param[i].value);
79			if (gets(buf) == NULL)
80			exit(0);
81			if (buf[0] == '?') {
82			puts(param[i].help);
83			continue;
84			}
85			if (buf[0])
86			strcpy(param[i].value, buf);
87			if (!(*param[i].check)(param[i].value)) {
88			fprintf(stderr, "%s: bad value for %s\n",
89			param[i].value, param[i].name);
90			continue;
91			}
92			i++;
93			}
94			compute();
95	greg	1.1	}
96	greg	1.2	}
97
98
99			typecheck(s) /* check lamp type */
100			char *s;
101			{
102			lampcolor = matchlamp(s);
103			return(lampcolor != NULL);
104			}
105
106
107			unitcheck(s) /* compute conversion to meters */
108			char *s;
109			{
110			int len = strlen(s);
111
112			switch (*s) {
113			case 'm':
114			if (strncmp(s, "meters", len))
115			return(0);
116			unit2meter = 1.0;
117			return(1);
118			case 'c':
119			if (strncmp(s, "centimeters", len) && strncmp(s, "cms", len))
120			return(0);
121			unit2meter = 0.01;
122			return(1);
123			case 'f':
124			if (strncmp(s, "foot", len) && strncmp(s, "feet", len))
125			return(0);
126			unit2meter = 0.3048;
127			return(1);
128			case 'i':
129			if (strncmp(s, "inches", len))
130			return(0);
131			unit2meter = 0.0254;
132			return(1);
133			}
134			return(0);
135			}
136
137
138			geomcheck(s) /* check/set lamp geometry */
139			char *s;
140			{
141			int len = strlen(s);
142
143			switch (*s) {
144			case 'p':
145			if (strncmp(s, "polygonal", len))
146			return(0);
147			return(getpolygon());
148			case 's':
149			if (strncmp(s, "sphere", len) && strncmp(s, "spherical", len))
150			return(0);
151			return(getsphere());
152			case 'c':
153			if (strncmp(s,"cylinder",len) && strncmp(s,"cylindrical",len))
154			return(0);
155			return(getcylinder());
156			case 'r':
157			if (strncmp(s, "ring", len) && strncmp(s, "disk", len))
158			return(0);
159			return(getring());
160			}
161			return(0);
162			}
163
164
165			outpcheck(s) /* check lumen output value */
166			register char *s;
167			{
168			if ((s < '0' \|\| s > '9') && *s != '.')
169			return(0);
170			lumens = atof(s);
171			return(1);
172			}
173
174
175			compute() /* compute lamp radiance */
176			{
177			double whiteval;
178
179	greg	1.8	whiteval = lumens/area/(WHTEFFICACY*PI);
180	greg	1.2
181			printf("Lamp color (RGB) = %f %f %f\n",
182			lampcolor[0]*whiteval,
183			lampcolor[1]*whiteval,
184			lampcolor[2]*whiteval);
185			}
186
187
188	greg	1.6	getd(name, dp, help) /* get a positive double from stdin */
189			char *name;
190	greg	1.2	double *dp;
191	greg	1.6	char *help;
192	greg	1.2	{
193			char buf[32];
194	greg	1.6	again:
195			printf("%s [%g]: ", name, *dp);
196	greg	1.2	if (gets(buf) == NULL)
197			return(0);
198	greg	1.6	if (buf[0] == '?') {
199			puts(help);
200			goto again;
201			}
202	greg	1.2	if ((buf[0] < '0' \|\| buf[0] > '9') && buf[0] != '.')
203			return(0);
204			*dp = atof(buf);
205			return(1);
206			}
207
208
209			getpolygon() /* get projected area for a polygon */
210			{
211	greg	1.9	static double parea = 1.0;
212	greg	1.5
213	greg	1.9	getd("Polygon area", &parea,
214	greg	1.6	"Enter the total radiating area of the polygon.");
215	greg	1.9	area = unit2meterunit2meter parea;
216	greg	1.2	return(1);
217			}
218
219
220			getsphere() /* get projected area for a sphere */
221			{
222	greg	1.5	static double radius = 1.0;
223	greg	1.2
224	greg	1.6	getd("Sphere radius", &radius,
225			"Enter the distance from the sphere's center to its surface.");
226	greg	1.7	area = 4.PIunit2meterunit2meter radius*radius;
227	greg	1.2	return(1);
228			}
229
230
231			getcylinder() /* get projected area for a cylinder */
232			{
233	greg	1.5	static double length = 1.0, radius = 0.1;
234	greg	1.2
235	greg	1.6	getd("Cylinder length", &length,
236			"Enter the length of the cylinder.");
237			getd("Cylinder radius", &radius,
238			"Enter the distance from the cylinder's axis to its surface.");
239	greg	1.7	area = 2.PIunit2meterunit2meter radius*length;
240	greg	1.2	return(1);
241			}
242
243
244			getring() /* get projected area for a ring */
245			{
246	greg	1.5	static double radius = 1.0;
247	greg	1.2
248	greg	1.6	getd("Disk radius", &radius,
249			"Enter the distance from the ring's center to its outer edge.\n\
250			The inner radius must be zero.");
251	greg	1.7	area = PIunit2meterunit2meter * radius*radius;
252	greg	1.2	return(1);
253	greg	1.1	}