src/cv/lampcolor.c

#ifndef lint
static const char       RCSid[] = "$Id: lampcolor.c,v 2.10 2004/03/18 05:22:00 greg Exp $";
#endif
/*
 * Program to convert lamp color from table and compute radiance.
 */

#include <math.h>

#include "rtmath.h"
#include "rtio.h"
#include "color.h"

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

static int typecheck(char *s);
static int unitcheck(char *s);
static int geomcheck(char *s);
static int outpcheck(char *s);
static void compute(void);
static int getpolygon(void), getsphere(void), getcylinder(void), getring(void);
static int getd(char *name, double *dp, char *help);


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." },
};


int
main(
        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 (fgetline(buf, sizeof(buf), stdin) == 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();
        }
}


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


static int
unitcheck(                      /* 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);
}


static int
geomcheck(                      /* 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);
}


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


static void
compute(void)                   /* 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);
}


static int
getd(           /* get a positive double from stdin */
        char    *name,
        double  *dp,
        char    *help
)
{
        char    buf[32];
again:
        printf("%s [%g]: ", name, *dp);
        if (fgets(buf, sizeof(buf), stdin) == 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);
}


static int
getpolygon(void)                        /* 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);
}


static int
getsphere(void)                 /* 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);
}


static int
getcylinder(void)                       /* 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);
}


static int
getring(void)                   /* 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:	2.11
Committed:	Sat Dec 28 18:05:14 2019 UTC (4 years, 4 months ago) by greg
Content type:	text/plain
Branch:	MAIN
CVS Tags:	rad5R4, rad5R3, HEAD
Changes since 2.10:	+1 -3 lines
Log Message:	Removed redundant include files
#	User	Rev	Content
1	greg	1.1	#ifndef lint
2	greg	2.11	static const char RCSid[] = "$Id: lampcolor.c,v 2.10 2004/03/18 05:22:00 greg Exp $";
3	greg	1.1	#endif
4			/*
5	greg	1.2	* Program to convert lamp color from table and compute radiance.
6	greg	1.1	*/
7
8	greg	2.4	#include <math.h>
9
10	schorsch	2.9	#include "rtmath.h"
11			#include "rtio.h"
12	greg	1.8	#include "color.h"
13	greg	1.2
14			/* lamp parameters */
15			#define LTYPE 0
16			#define LUNIT 1
17			#define LGEOM 2
18			#define LOUTP 3
19			#define NPARAMS 4
20	greg	1.1
21	schorsch	2.7	static int typecheck(char *s);
22			static int unitcheck(char *s);
23			static int geomcheck(char *s);
24			static int outpcheck(char *s);
25			static void compute(void);
26			static int getpolygon(void), getsphere(void), getcylinder(void), getring(void);
27	schorsch	2.9	static int getd(char name, double dp, char *help);
28	schorsch	2.7
29	greg	1.2
30			float lampcolor; / the lamp color (RGB) */
31			double unit2meter; /* conversion from units to meters */
32	greg	1.7	double area; /* radiating area for this geometry */
33	greg	1.2	double lumens; /* total lamp lumens */
34
35			struct {
36			char *name;
37			char value[64];
38			int (*check)();
39			char *help;
40			} param[NPARAMS] = {
41	saba	2.5	{ "lamp type", "WHITE", typecheck,
42	greg	1.2	"The lamp type is a string which corresponds to one of the types registered\n\
43	saba	2.5	in the lamp table file. A value of \"WHITE\" means an uncolored source,\n\
44	greg	1.2	which may be preferable because it results in a color balanced image." },
45			{ "length unit", "meter", unitcheck,
46			"Unit must be one of: \"meter\", \"centimeter\", \"foot\", or \"inch\".\n\
47			These may be abbreviated as a single letter." },
48			{ "lamp geometry", "polygon", geomcheck,
49			"The lamp geometry must be one of: \"polygon\", \"sphere\", \"cylinder\"\n\
50			or \"ring\". These may be abbreviated as a single letter." },
51			{ "total lamp lumens", "0", outpcheck,
52			"This is the overall light output of the lamp and its fixture. If you do\n\
53			not know this value explicitly, you can compute the approximate lumens\n\
54	greg	1.3	by multiplying the input wattage by 14 for incandescent fixtures or 70\n\
55	greg	1.2	for fluorescent fixtures." },
56			};
57
58
59	schorsch	2.9	int
60			main(
61			int argc,
62			char *argv[]
63			)
64	greg	1.1	{
65			char *lamptab = "lamp.tab";
66	greg	1.2	char buf[64];
67			int i;
68	greg	1.1
69			if (argc > 1) lamptab = argv[1];
70			if (loadlamps(lamptab) == 0) {
71	greg	1.2	fprintf(stderr, "%s: no such lamp table\n", lamptab);
72	greg	1.1	exit(1);
73			}
74	greg	1.2	printf("Program to compute lamp radiance. Enter '?' for help.\n");
75	greg	1.1	for ( ; ; ) {
76	greg	1.2	i = 0;
77			while (i < NPARAMS) {
78			printf("Enter %s [%s]: ", param[i].name,
79			param[i].value);
80	greg	2.10	if (fgetline(buf, sizeof(buf), stdin) == NULL)
81	greg	1.2	exit(0);
82			if (buf[0] == '?') {
83			puts(param[i].help);
84			continue;
85			}
86			if (buf[0])
87			strcpy(param[i].value, buf);
88			if (!(*param[i].check)(param[i].value)) {
89			fprintf(stderr, "%s: bad value for %s\n",
90			param[i].value, param[i].name);
91			continue;
92			}
93			i++;
94			}
95			compute();
96	greg	1.1	}
97	greg	1.2	}
98
99
100	schorsch	2.7	static int
101			typecheck( /* check lamp type */
102	schorsch	2.9	char *s
103	schorsch	2.7	)
104	greg	1.2	{
105			lampcolor = matchlamp(s);
106			return(lampcolor != NULL);
107			}
108
109
110	schorsch	2.7	static int
111			unitcheck( /* compute conversion to meters */
112	schorsch	2.9	char *s
113	schorsch	2.7	)
114	greg	1.2	{
115			int len = strlen(s);
116
117			switch (*s) {
118			case 'm':
119			if (strncmp(s, "meters", len))
120			return(0);
121			unit2meter = 1.0;
122			return(1);
123			case 'c':
124			if (strncmp(s, "centimeters", len) && strncmp(s, "cms", len))
125			return(0);
126			unit2meter = 0.01;
127			return(1);
128			case 'f':
129			if (strncmp(s, "foot", len) && strncmp(s, "feet", len))
130			return(0);
131			unit2meter = 0.3048;
132			return(1);
133			case 'i':
134			if (strncmp(s, "inches", len))
135			return(0);
136			unit2meter = 0.0254;
137			return(1);
138			}
139			return(0);
140			}
141
142
143	schorsch	2.7	static int
144			geomcheck( /* check/set lamp geometry */
145	schorsch	2.9	char *s
146	schorsch	2.7	)
147	greg	1.2	{
148			int len = strlen(s);
149
150			switch (*s) {
151			case 'p':
152			if (strncmp(s, "polygonal", len))
153			return(0);
154			return(getpolygon());
155			case 's':
156			if (strncmp(s, "sphere", len) && strncmp(s, "spherical", len))
157			return(0);
158			return(getsphere());
159			case 'c':
160			if (strncmp(s,"cylinder",len) && strncmp(s,"cylindrical",len))
161			return(0);
162			return(getcylinder());
163			case 'r':
164			if (strncmp(s, "ring", len) && strncmp(s, "disk", len))
165			return(0);
166			return(getring());
167			}
168			return(0);
169			}
170
171
172	schorsch	2.7	static int
173			outpcheck( /* check lumen output value */
174	schorsch	2.9	register char *s
175	schorsch	2.7	)
176	greg	1.2	{
177			if ((s < '0' \|\| s > '9') && *s != '.')
178			return(0);
179			lumens = atof(s);
180			return(1);
181			}
182
183
184	schorsch	2.7	static void
185			compute(void) /* compute lamp radiance */
186	greg	1.2	{
187			double whiteval;
188
189	greg	1.8	whiteval = lumens/area/(WHTEFFICACY*PI);
190	greg	1.2
191			printf("Lamp color (RGB) = %f %f %f\n",
192			lampcolor[0]*whiteval,
193			lampcolor[1]*whiteval,
194			lampcolor[2]*whiteval);
195			}
196
197
198	schorsch	2.9	static int
199			getd( /* get a positive double from stdin */
200			char *name,
201			double *dp,
202			char *help
203			)
204	greg	1.2	{
205			char buf[32];
206	greg	1.6	again:
207			printf("%s [%g]: ", name, *dp);
208	schorsch	2.9	if (fgets(buf, sizeof(buf), stdin) == NULL)
209	greg	1.2	return(0);
210	greg	1.6	if (buf[0] == '?') {
211			puts(help);
212			goto again;
213			}
214	greg	1.2	if ((buf[0] < '0' \|\| buf[0] > '9') && buf[0] != '.')
215			return(0);
216			*dp = atof(buf);
217			return(1);
218			}
219
220
221	schorsch	2.7	static int
222			getpolygon(void) /* get projected area for a polygon */
223	greg	1.2	{
224	greg	1.9	static double parea = 1.0;
225	greg	1.5
226	greg	1.9	getd("Polygon area", &parea,
227	greg	1.6	"Enter the total radiating area of the polygon.");
228	greg	1.9	area = unit2meterunit2meter parea;
229	greg	1.2	return(1);
230			}
231
232
233	schorsch	2.7	static int
234			getsphere(void) /* get projected area for a sphere */
235	greg	1.2	{
236	greg	1.5	static double radius = 1.0;
237	greg	1.2
238	greg	1.6	getd("Sphere radius", &radius,
239			"Enter the distance from the sphere's center to its surface.");
240	greg	1.7	area = 4.PIunit2meterunit2meter radius*radius;
241	greg	1.2	return(1);
242			}
243
244
245	schorsch	2.7	static int
246			getcylinder(void) /* get projected area for a cylinder */
247	greg	1.2	{
248	greg	1.5	static double length = 1.0, radius = 0.1;
249	greg	1.2
250	greg	1.6	getd("Cylinder length", &length,
251			"Enter the length of the cylinder.");
252			getd("Cylinder radius", &radius,
253			"Enter the distance from the cylinder's axis to its surface.");
254	greg	1.7	area = 2.PIunit2meterunit2meter radius*length;
255	greg	1.2	return(1);
256			}
257
258
259	schorsch	2.7	static int
260			getring(void) /* get projected area for a ring */
261	greg	1.2	{
262	greg	1.5	static double radius = 1.0;
263	greg	1.2
264	greg	1.6	getd("Disk radius", &radius,
265			"Enter the distance from the ring's center to its outer edge.\n\
266			The inner radius must be zero.");
267	greg	1.7	area = PIunit2meterunit2meter * radius*radius;
268	greg	1.2	return(1);
269	greg	1.1	}