src/cv/lampcolor.c

#ifndef lint
static const char       RCSid[] = "$Id: lampcolor.c,v 2.8 2003/06/21 15:05:01 greg Exp $";
#endif
/*
 * Program to convert lamp color from table and compute radiance.
 */

#include <stdio.h>
#include <string.h>
#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 (fgets(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:	2.9
Committed:	Sat Nov 15 17:54:06 2003 UTC (20 years, 11 months ago) by schorsch
Content type:	text/plain
Branch:	MAIN
Changes since 2.8:	+21 -15 lines
Log Message:	Continued ANSIfication and reduced compile warnings.
#	User	Rev	Content
1	greg	1.1	#ifndef lint
2	schorsch	2.9	static const char RCSid[] = "$Id: lampcolor.c,v 2.8 2003/06/21 15:05:01 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			#include <stdio.h>
9	schorsch	2.7	#include <string.h>
10	greg	2.4	#include <math.h>
11
12	schorsch	2.9	#include "rtmath.h"
13			#include "rtio.h"
14	greg	1.8	#include "color.h"
15	greg	1.2
16			/* lamp parameters */
17			#define LTYPE 0
18			#define LUNIT 1
19			#define LGEOM 2
20			#define LOUTP 3
21			#define NPARAMS 4
22	greg	1.1
23	schorsch	2.7	static int typecheck(char *s);
24			static int unitcheck(char *s);
25			static int geomcheck(char *s);
26			static int outpcheck(char *s);
27			static void compute(void);
28			static int getpolygon(void), getsphere(void), getcylinder(void), getring(void);
29	schorsch	2.9	static int getd(char name, double dp, char *help);
30	schorsch	2.7
31	greg	1.2
32			float lampcolor; / the lamp color (RGB) */
33			double unit2meter; /* conversion from units to meters */
34	greg	1.7	double area; /* radiating area for this geometry */
35	greg	1.2	double lumens; /* total lamp lumens */
36
37			struct {
38			char *name;
39			char value[64];
40			int (*check)();
41			char *help;
42			} param[NPARAMS] = {
43	saba	2.5	{ "lamp type", "WHITE", typecheck,
44	greg	1.2	"The lamp type is a string which corresponds to one of the types registered\n\
45	saba	2.5	in the lamp table file. A value of \"WHITE\" means an uncolored source,\n\
46	greg	1.2	which may be preferable because it results in a color balanced image." },
47			{ "length unit", "meter", unitcheck,
48			"Unit must be one of: \"meter\", \"centimeter\", \"foot\", or \"inch\".\n\
49			These may be abbreviated as a single letter." },
50			{ "lamp geometry", "polygon", geomcheck,
51			"The lamp geometry must be one of: \"polygon\", \"sphere\", \"cylinder\"\n\
52			or \"ring\". These may be abbreviated as a single letter." },
53			{ "total lamp lumens", "0", outpcheck,
54			"This is the overall light output of the lamp and its fixture. If you do\n\
55			not know this value explicitly, you can compute the approximate lumens\n\
56	greg	1.3	by multiplying the input wattage by 14 for incandescent fixtures or 70\n\
57	greg	1.2	for fluorescent fixtures." },
58			};
59
60
61	schorsch	2.9	int
62			main(
63			int argc,
64			char *argv[]
65			)
66	greg	1.1	{
67			char *lamptab = "lamp.tab";
68	greg	1.2	char buf[64];
69			int i;
70	greg	1.1
71			if (argc > 1) lamptab = argv[1];
72			if (loadlamps(lamptab) == 0) {
73	greg	1.2	fprintf(stderr, "%s: no such lamp table\n", lamptab);
74	greg	1.1	exit(1);
75			}
76	greg	1.2	printf("Program to compute lamp radiance. Enter '?' for help.\n");
77	greg	1.1	for ( ; ; ) {
78	greg	1.2	i = 0;
79			while (i < NPARAMS) {
80			printf("Enter %s [%s]: ", param[i].name,
81			param[i].value);
82	schorsch	2.9	if (fgets(buf, sizeof(buf), stdin) == NULL)
83	greg	1.2	exit(0);
84			if (buf[0] == '?') {
85			puts(param[i].help);
86			continue;
87			}
88			if (buf[0])
89			strcpy(param[i].value, buf);
90			if (!(*param[i].check)(param[i].value)) {
91			fprintf(stderr, "%s: bad value for %s\n",
92			param[i].value, param[i].name);
93			continue;
94			}
95			i++;
96			}
97			compute();
98	greg	1.1	}
99	greg	1.2	}
100
101
102	schorsch	2.7	static int
103			typecheck( /* check lamp type */
104	schorsch	2.9	char *s
105	schorsch	2.7	)
106	greg	1.2	{
107			lampcolor = matchlamp(s);
108			return(lampcolor != NULL);
109			}
110
111
112	schorsch	2.7	static int
113			unitcheck( /* compute conversion to meters */
114	schorsch	2.9	char *s
115	schorsch	2.7	)
116	greg	1.2	{
117			int len = strlen(s);
118
119			switch (*s) {
120			case 'm':
121			if (strncmp(s, "meters", len))
122			return(0);
123			unit2meter = 1.0;
124			return(1);
125			case 'c':
126			if (strncmp(s, "centimeters", len) && strncmp(s, "cms", len))
127			return(0);
128			unit2meter = 0.01;
129			return(1);
130			case 'f':
131			if (strncmp(s, "foot", len) && strncmp(s, "feet", len))
132			return(0);
133			unit2meter = 0.3048;
134			return(1);
135			case 'i':
136			if (strncmp(s, "inches", len))
137			return(0);
138			unit2meter = 0.0254;
139			return(1);
140			}
141			return(0);
142			}
143
144
145	schorsch	2.7	static int
146			geomcheck( /* check/set lamp geometry */
147	schorsch	2.9	char *s
148	schorsch	2.7	)
149	greg	1.2	{
150			int len = strlen(s);
151
152			switch (*s) {
153			case 'p':
154			if (strncmp(s, "polygonal", len))
155			return(0);
156			return(getpolygon());
157			case 's':
158			if (strncmp(s, "sphere", len) && strncmp(s, "spherical", len))
159			return(0);
160			return(getsphere());
161			case 'c':
162			if (strncmp(s,"cylinder",len) && strncmp(s,"cylindrical",len))
163			return(0);
164			return(getcylinder());
165			case 'r':
166			if (strncmp(s, "ring", len) && strncmp(s, "disk", len))
167			return(0);
168			return(getring());
169			}
170			return(0);
171			}
172
173
174	schorsch	2.7	static int
175			outpcheck( /* check lumen output value */
176	schorsch	2.9	register char *s
177	schorsch	2.7	)
178	greg	1.2	{
179			if ((s < '0' \|\| s > '9') && *s != '.')
180			return(0);
181			lumens = atof(s);
182			return(1);
183			}
184
185
186	schorsch	2.7	static void
187			compute(void) /* compute lamp radiance */
188	greg	1.2	{
189			double whiteval;
190
191	greg	1.8	whiteval = lumens/area/(WHTEFFICACY*PI);
192	greg	1.2
193			printf("Lamp color (RGB) = %f %f %f\n",
194			lampcolor[0]*whiteval,
195			lampcolor[1]*whiteval,
196			lampcolor[2]*whiteval);
197			}
198
199
200	schorsch	2.9	static int
201			getd( /* get a positive double from stdin */
202			char *name,
203			double *dp,
204			char *help
205			)
206	greg	1.2	{
207			char buf[32];
208	greg	1.6	again:
209			printf("%s [%g]: ", name, *dp);
210	schorsch	2.9	if (fgets(buf, sizeof(buf), stdin) == NULL)
211	greg	1.2	return(0);
212	greg	1.6	if (buf[0] == '?') {
213			puts(help);
214			goto again;
215			}
216	greg	1.2	if ((buf[0] < '0' \|\| buf[0] > '9') && buf[0] != '.')
217			return(0);
218			*dp = atof(buf);
219			return(1);
220			}
221
222
223	schorsch	2.7	static int
224			getpolygon(void) /* get projected area for a polygon */
225	greg	1.2	{
226	greg	1.9	static double parea = 1.0;
227	greg	1.5
228	greg	1.9	getd("Polygon area", &parea,
229	greg	1.6	"Enter the total radiating area of the polygon.");
230	greg	1.9	area = unit2meterunit2meter parea;
231	greg	1.2	return(1);
232			}
233
234
235	schorsch	2.7	static int
236			getsphere(void) /* get projected area for a sphere */
237	greg	1.2	{
238	greg	1.5	static double radius = 1.0;
239	greg	1.2
240	greg	1.6	getd("Sphere radius", &radius,
241			"Enter the distance from the sphere's center to its surface.");
242	greg	1.7	area = 4.PIunit2meterunit2meter radius*radius;
243	greg	1.2	return(1);
244			}
245
246
247	schorsch	2.7	static int
248			getcylinder(void) /* get projected area for a cylinder */
249	greg	1.2	{
250	greg	1.5	static double length = 1.0, radius = 0.1;
251	greg	1.2
252	greg	1.6	getd("Cylinder length", &length,
253			"Enter the length of the cylinder.");
254			getd("Cylinder radius", &radius,
255			"Enter the distance from the cylinder's axis to its surface.");
256	greg	1.7	area = 2.PIunit2meterunit2meter radius*length;
257	greg	1.2	return(1);
258			}
259
260
261	schorsch	2.7	static int
262			getring(void) /* get projected area for a ring */
263	greg	1.2	{
264	greg	1.5	static double radius = 1.0;
265	greg	1.2
266	greg	1.6	getd("Disk radius", &radius,
267			"Enter the distance from the ring's center to its outer edge.\n\
268			The inner radius must be zero.");
269	greg	1.7	area = PIunit2meterunit2meter * radius*radius;
270	greg	1.2	return(1);
271	greg	1.1	}