Geografic-Information-System/lib/gis/named_colr.c

#include <grass/gis.h>
#include <string.h>
#include <stdio.h>

static struct
{
    const char *name;
    float r, g, b;
} colors[] = {
    {"white",  1.00, 1.00, 1.00},
    {"black",  0.00, 0.00, 0.00},
    {"red",    1.00, 0.00, 0.00},
    {"green",  0.00, 1.00, 0.00},
    {"blue",   0.00, 0.00, 1.00},
    {"yellow", 1.00, 1.00, 0.00},
    {"magenta",1.00, 0.00, 1.00},
    {"cyan",   0.00, 1.00, 1.00},
    {"aqua",   0.00, 0.75, 0.75},
    {"grey",   0.75, 0.75, 0.75},
    {"gray",   0.75, 0.75, 0.75},
    {"orange", 1.00, 0.50, 0.00},
    {"brown",  0.75, 0.50, 0.25},
    {"purple", 0.50, 0.00, 1.00},
    {"violet", 0.50, 0.00, 1.00},
    {"indigo", 0.00, 0.50, 1.00},
    {"",       0.00, 0.00, 0.00}	/* do not modify this line */
};

int G_color_values(const char *name, float *r, float *g, float *b)
{
    int i;

    *r = *g = *b = 0.0;
    for (i = 0; colors[i].name[0]; i++)
	if (strcmp(name, colors[i].name) == 0) {
	    *r = colors[i].r;
	    *g = colors[i].g;
	    *b = colors[i].b;
	    return 1;
	}
    return -1;
}

const char *G_color_name(int n)
{
    int i;

    if (n >= 0)
	for (i = 0; colors[i].name[0]; i++)
	    if (i == n)
		return colors[i].name;
    return NULL;
}