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>

#define PI      3.14159265358979323846

extern char     *gets(), *strcpy();
extern double   atof();
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  projarea;               /* projected 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/470./projarea;

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


getd(dp)                        /* get a positive double from stdin */
double  *dp;
{
        char    buf[32];

        if (gets(buf) == NULL)
                return(0);
        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   area = 1.0;

        printf("Polygon area [%g]: ", area);
        getd(&area);
        projarea = PI*unit2meter*unit2meter * area;
        return(1);
}


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

        printf("Sphere radius [%g]: ", radius);
        getd(&radius);
        projarea = 4.*PI*PI*unit2meter*unit2meter * radius*radius;
        return(1);
}


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

        printf("Cylinder length [%g]: ", length);
        getd(&length);
        printf("Cylinder radius [%g]: ", radius);
        getd(&radius);
        projarea = PI*PI*2.*PI*unit2meter*unit2meter * radius*length;
        return(1);
}


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

        printf("Disk radius [%g]: ", radius);
        getd(&radius);
        projarea = PI*PI*unit2meter*unit2meter * radius*radius;
        return(1);
}
Revision:	1.5
Committed:	Thu Sep 12 13:26:16 1991 UTC (32 years, 7 months ago) by greg
Content type:	text/plain
Branch:	MAIN
Changes since 1.4:	+19 -27 lines
Log Message:	added defaults to geometries
#	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	1.2	#define PI 3.14159265358979323846
14
15			extern char gets(), strcpy();
16			extern double atof();
17	greg	1.1	extern float *matchlamp();
18
19	greg	1.2	/* lamp parameters */
20			#define LTYPE 0
21			#define LUNIT 1
22			#define LGEOM 2
23			#define LOUTP 3
24			#define NPARAMS 4
25	greg	1.1
26	greg	1.2	int typecheck(), unitcheck(), geomcheck(), outpcheck();
27
28			float lampcolor; / the lamp color (RGB) */
29			double unit2meter; /* conversion from units to meters */
30			double projarea; /* projected area for this geometry */
31			double lumens; /* total lamp lumens */
32
33			struct {
34			char *name;
35			char value[64];
36			int (*check)();
37			char *help;
38			} param[NPARAMS] = {
39			{ "lamp type", "white", typecheck,
40			"The lamp type is a string which corresponds to one of the types registered\n\
41			in the lamp table file. A value of \"white\" means an uncolored source,\n\
42			which may be preferable because it results in a color balanced image." },
43			{ "length unit", "meter", unitcheck,
44			"Unit must be one of: \"meter\", \"centimeter\", \"foot\", or \"inch\".\n\
45			These may be abbreviated as a single letter." },
46			{ "lamp geometry", "polygon", geomcheck,
47			"The lamp geometry must be one of: \"polygon\", \"sphere\", \"cylinder\"\n\
48			or \"ring\". These may be abbreviated as a single letter." },
49			{ "total lamp lumens", "0", outpcheck,
50			"This is the overall light output of the lamp and its fixture. If you do\n\
51			not know this value explicitly, you can compute the approximate lumens\n\
52	greg	1.3	by multiplying the input wattage by 14 for incandescent fixtures or 70\n\
53	greg	1.2	for fluorescent fixtures." },
54			};
55
56
57	greg	1.1	main(argc, argv)
58			int argc;
59			char *argv[];
60			{
61			char *lamptab = "lamp.tab";
62	greg	1.2	char buf[64];
63			int i;
64	greg	1.1
65			if (argc > 1) lamptab = argv[1];
66			if (loadlamps(lamptab) == 0) {
67	greg	1.2	fprintf(stderr, "%s: no such lamp table\n", lamptab);
68	greg	1.1	exit(1);
69			}
70	greg	1.2	printf("Program to compute lamp radiance. Enter '?' for help.\n");
71	greg	1.1	for ( ; ; ) {
72	greg	1.2	i = 0;
73			while (i < NPARAMS) {
74			printf("Enter %s [%s]: ", param[i].name,
75			param[i].value);
76			if (gets(buf) == NULL)
77			exit(0);
78			if (buf[0] == '?') {
79			puts(param[i].help);
80			continue;
81			}
82			if (buf[0])
83			strcpy(param[i].value, buf);
84			if (!(*param[i].check)(param[i].value)) {
85			fprintf(stderr, "%s: bad value for %s\n",
86			param[i].value, param[i].name);
87			continue;
88			}
89			i++;
90			}
91			compute();
92	greg	1.1	}
93	greg	1.2	}
94
95
96			typecheck(s) /* check lamp type */
97			char *s;
98			{
99			lampcolor = matchlamp(s);
100			return(lampcolor != NULL);
101			}
102
103
104			unitcheck(s) /* compute conversion to meters */
105			char *s;
106			{
107			int len = strlen(s);
108
109			switch (*s) {
110			case 'm':
111			if (strncmp(s, "meters", len))
112			return(0);
113			unit2meter = 1.0;
114			return(1);
115			case 'c':
116			if (strncmp(s, "centimeters", len) && strncmp(s, "cms", len))
117			return(0);
118			unit2meter = 0.01;
119			return(1);
120			case 'f':
121			if (strncmp(s, "foot", len) && strncmp(s, "feet", len))
122			return(0);
123			unit2meter = 0.3048;
124			return(1);
125			case 'i':
126			if (strncmp(s, "inches", len))
127			return(0);
128			unit2meter = 0.0254;
129			return(1);
130			}
131			return(0);
132			}
133
134
135			geomcheck(s) /* check/set lamp geometry */
136			char *s;
137			{
138			int len = strlen(s);
139
140			switch (*s) {
141			case 'p':
142			if (strncmp(s, "polygonal", len))
143			return(0);
144			return(getpolygon());
145			case 's':
146			if (strncmp(s, "sphere", len) && strncmp(s, "spherical", len))
147			return(0);
148			return(getsphere());
149			case 'c':
150			if (strncmp(s,"cylinder",len) && strncmp(s,"cylindrical",len))
151			return(0);
152			return(getcylinder());
153			case 'r':
154			if (strncmp(s, "ring", len) && strncmp(s, "disk", len))
155			return(0);
156			return(getring());
157			}
158			return(0);
159			}
160
161
162			outpcheck(s) /* check lumen output value */
163			register char *s;
164			{
165			if ((s < '0' \|\| s > '9') && *s != '.')
166			return(0);
167			lumens = atof(s);
168			return(1);
169			}
170
171
172			compute() /* compute lamp radiance */
173			{
174			double whiteval;
175
176			whiteval = lumens/470./projarea;
177
178			printf("Lamp color (RGB) = %f %f %f\n",
179			lampcolor[0]*whiteval,
180			lampcolor[1]*whiteval,
181			lampcolor[2]*whiteval);
182			}
183
184
185			getd(dp) /* get a positive double from stdin */
186			double *dp;
187			{
188			char buf[32];
189
190			if (gets(buf) == NULL)
191			return(0);
192			if ((buf[0] < '0' \|\| buf[0] > '9') && buf[0] != '.')
193			return(0);
194			*dp = atof(buf);
195			return(1);
196			}
197
198
199			getpolygon() /* get projected area for a polygon */
200			{
201	greg	1.5	static double area = 1.0;
202
203			printf("Polygon area [%g]: ", area);
204			getd(&area);
205			projarea = PIunit2meterunit2meter * area;
206	greg	1.2	return(1);
207			}
208
209
210			getsphere() /* get projected area for a sphere */
211			{
212	greg	1.5	static double radius = 1.0;
213	greg	1.2
214	greg	1.5	printf("Sphere radius [%g]: ", radius);
215			getd(&radius);
216			projarea = 4.PIPIunit2meterunit2meter * radius*radius;
217	greg	1.2	return(1);
218			}
219
220
221			getcylinder() /* get projected area for a cylinder */
222			{
223	greg	1.5	static double length = 1.0, radius = 0.1;
224	greg	1.2
225	greg	1.5	printf("Cylinder length [%g]: ", length);
226			getd(&length);
227			printf("Cylinder radius [%g]: ", radius);
228			getd(&radius);
229			projarea = PIPI2.PIunit2meterunit2meter radius*length;
230	greg	1.2	return(1);
231			}
232
233
234			getring() /* get projected area for a ring */
235			{
236	greg	1.5	static double radius = 1.0;
237	greg	1.2
238	greg	1.5	printf("Disk radius [%g]: ", radius);
239			getd(&radius);
240			projarea = PIPIunit2meterunit2meter radius*radius;
241	greg	1.2	return(1);
242	greg	1.1	}