/* Program to open an XWindow and test the set of available colors.

Written by Dan Harvey, 5/7/2002
To compile: gcc -g -o rgb rgb.c -L/usr/X11R6/lib -lX11

*/

#include <stdio.h>
#include <X11/Xlib.h>
#include <X11/Xutil.h>
#include <X11/Xos.h>

/* Required constants */

#define WIDTH 800 /* Resolution of screen */
#define HEIGHT 800
#define BORDER 4
#define MAX_COLORS 600 /* Maximum size of array of colors. */
#define SLEEP_TIME 10 /* Time to delay before exiting. */

/* Data structures */

static char *colorNames[] = {
"snow","GhostWhite","WhiteSmoke","gainsboro","FloralWhite","OldLace",
"linen","AntiqueWhite","PapayaWhip","BlanchedAlmond","bisque","PeachPuff",
"NavajoWhite","moccasin","cornsilk","ivory","LemonChiffon","seashell",
"honeydew","MintCream","azure","AliceBlue","lavender","LavenderBlush",
"MistyRose","white","black","DarkSlateGrey","DimGrey","SlateGrey",
"LightSlateGrey","grey","LightGrey","LightGray","MidnightBlue","navy",
"NavyBlue","CornflowerBlue","DarkSlateBlue","SlateBlue","MediumSlateBlue",
"LightSlateBlue","MediumBlue","RoyalBlue","blue","DodgerBlue","DeepSkyBlue",
"SkyBlue","LightSkyBlue","SteelBlue","LightSteelBlue","LightBlue",
"PowderBlue","PaleTurquoise","DarkTurquoise","MediumTurquoise",
"turquoise","cyan","LightCyan","CadetBlue","MediumAquamarine","aquamarine",
"DarkGreen","DarkOliveGreen","DarkSeaGreen","SeaGreen","MediumSeaGreen",
"LightSeaGreen","PaleGreen","SpringGreen","LawnGreen","green","chartreuse",
"MediumSpringGreen","GreenYellow","lime green","LimeGreen","YellowGreen",
"ForestGreen","OliveDrab","DarkKhaki","khaki","PaleGoldenrod",
"LightGoldenrodYellow", "LightYellow","yellow","gold","LightGoldenrod",
"goldenrod","DarkGoldenrod","RosyBrown","IndianRed","SaddleBrown","sienna",
"peru","burlywood","beige","wheat","SandyBrown","tan","chocolate",
"firebrick","brown","DarkSalmon","salmon","LightSalmon","orange",
"DarkOrange","coral","LightCoral","tomato","OrangeRed","red","HotPink",
"DeepPink","pink","LightPink","PaleVioletRed","maroon","MediumVioletRed",
"VioletRed","magenta","violet","plum","orchid","MediumOrchid","DarkOrchid",
"DarkViolet","BlueViolet","purple","MediumPurple","thistle","snow1","snow2",
"snow3","snow4","seashell1","seashell2","seashell3","seashell4",
"AntiqueWhite1","AntiqueWhite2","AntiqueWhite3","AntiqueWhite4","bisque1",
"bisque2","bisque3","bisque4","PeachPuff1","PeachPuff2","PeachPuff3",
"PeachPuff4","NavajoWhite1","NavajoWhite2","NavajoWhite3","NavajoWhite4",
"LemonChiffon1","LemonChiffon2","LemonChiffon3","LemonChiffon4","cornsilk1",
"cornsilk2","cornsilk3","cornsilk4","ivory1","ivory2","ivory3","ivory4",
"honeydew1","honeydew2","honeydew3","honeydew4","LavenderBlush1",
"LavenderBlush2","LavenderBlush3","LavenderBlush4","MistyRose1",
"MistyRose2","MistyRose3","MistyRose4","azure1","azure2","azure3","azure4",
"SlateBlue1","SlateBlue2","SlateBlue3","SlateBlue4","RoyalBlue1",
"RoyalBlue2","RoyalBlue3","RoyalBlue4","blue1","blue2","blue3","blue4",
"DodgerBlue1","DodgerBlue2","DodgerBlue3","DodgerBlue4","SteelBlue1",
"SteelBlue2","SteelBlue3","SteelBlue4","DeepSkyBlue1","DeepSkyBlue2",
"DeepSkyBlue3","DeepSkyBlue4","SkyBlue1","SkyBlue2","SkyBlue3","SkyBlue4",
"LightSkyBlue1","LightSkyBlue2","LightSkyBlue3","LightSkyBlue4",
"SlateGray1","SlateGray2","SlateGray3","SlateGray4", "LightSteelBlue1",
"LightSteelBlue2","LightSteelBlue3","LightSteelBlue4","LightBlue1",
"LightBlue2","LightBlue3","LightBlue4","LightCyan1","LightCyan2",
"LightCyan3","LightCyan4","PaleTurquoise1","PaleTurquoise2",
"PaleTurquoise3","PaleTurquoise4","CadetBlue1","CadetBlue2","CadetBlue3",
"CadetBlue4","turquoise1","turquoise2","turquoise3","turquoise4","cyan1",
"cyan2","cyan3","cyan4","DarkSlateGray1","DarkSlateGray2","DarkSlateGray3",
"DarkSlateGray4","aquamarine1","aquamarine2","aquamarine3","aquamarine4",
"DarkSeaGreen1","DarkSeaGreen2","DarkSeaGreen3","DarkSeaGreen4","SeaGreen1",
"SeaGreen2","SeaGreen3","SeaGreen4","PaleGreen1","PaleGreen2","PaleGreen3",
"PaleGreen4","SpringGreen1","SpringGreen2","SpringGreen3","SpringGreen4",
"green1","green2","green3","green4","chartreuse1","chartreuse2",
"chartreuse3","chartreuse4","OliveDrab1","OliveDrab2","OliveDrab3",
"OliveDrab4","DarkOliveGreen1","DarkOliveGreen2","DarkOliveGreen3",
"DarkOliveGreen4","khaki1","khaki2","khaki3","khaki4","LightGoldenrod1",
"LightGoldenrod2","LightGoldenrod3","LightGoldenrod4","LightYellow1",
"LightYellow2","LightYellow3","LightYellow4","yellow1","yellow2","yellow3",
"yellow4","gold1","gold2","gold3","gold4","goldenrod1","goldenrod2",
"goldenrod3","goldenrod4","DarkGoldenrod1","DarkGoldenrod2",
"DarkGoldenrod3","DarkGoldenrod4","RosyBrown1","RosyBrown2","RosyBrown3",
"RosyBrown4","IndianRed1","IndianRed2","IndianRed3","IndianRed4","sienna1",
"sienna2","sienna3","sienna4","burlywood1","burlywood2","burlywood3",
"burlywood4","wheat1","wheat2","wheat3","wheat4","tan1","tan2","tan3",
"tan4","chocolate1","chocolate2","chocolate3","chocolate4","firebrick1",
"firebrick2","firebrick3","firebrick4","brown1","brown2","brown3","brown4",
"salmon1","salmon2","salmon3","salmon4","LightSalmon1","LightSalmon2",
"LightSalmon3","LightSalmon4","orange1","orange2","orange3","orange4",
"DarkOrange1","DarkOrange2","DarkOrange3","DarkOrange4","coral1","coral2",
"coral3","coral4","tomato1","tomato2","tomato3","tomato4","OrangeRed1",
"OrangeRed2","OrangeRed3", "OrangeRed4","red1","red2","red3","red4",
"DeepPink1","DeepPink2","DeepPink3","DeepPink4","HotPink1","HotPink2",
"HotPink3","HotPink4","pink1","pink2","pink3", "pink4","LightPink1",
"LightPink2","LightPink3","LightPink4","PaleVioletRed1","PaleVioletRed2",
"PaleVioletRed3","PaleVioletRed4","maroon1","maroon2","maroon3","maroon4",
"VioletRed1","VioletRed2","VioletRed3","VioletRed4","magenta1","magenta2",
"magenta3","magenta4","orchid1","orchid2","orchid3","orchid4","plum1",
"plum2","plum3","plum4","MediumOrchid1","MediumOrchid2","MediumOrchid3",
"MediumOrchid4","DarkOrchid1","DarkOrchid2","DarkOrchid3","DarkOrchid4",
"purple1","purple2","purple3","purple4","MediumPurple1","MediumPurple2",
"MediumPurple3","MediumPurple4","thistle1","thistle2","thistle3",
"thistle4","grey0","grey1","grey2","grey3","grey4","grey5","grey6","grey7",
"grey8","grey9","grey10","grey11","grey12","grey13","grey14","grey15",
"grey16","grey17","grey18","grey19","grey20","grey21","grey22","grey23",
"grey24","grey25","grey26","grey27","grey28","grey29","grey30","grey31",
"grey32","grey33","grey34","grey35","grey36","grey37","grey38","grey39",
"grey40","grey41","grey42","grey43","grey44","grey45","grey46","grey47",
"grey48","grey49","grey50","grey51","grey52","grey53","grey54","gray55",
"grey55","gray56","grey56","grey57","grey58","grey59","grey60","grey61",
"grey62","grey63","grey64","grey65","grey66","grey67","grey68","grey69",
"grey70","grey71","grey72","grey73","grey74","grey75","grey76","grey77",
"grey78","grey79","grey80","grey81","grey82","grey83","grey84","grey85",
"grey86","grey87","grey88","grey89","grey90","grey91","grey92","grey93",
"grey94","grey95","grey96","grey97","grey98","grey99","grey100","DarkGrey",
"DarkBlue","DarkCyan","DarkMagenta","DarkRed","LightGreen",""
};

/* Verify list of colors. */

int verifyColors(Display *display,int screen,
char *colorList[],unsigned long rgb[])
{ Colormap colormap = DefaultColormap(display, screen);
int color = 0, colors = 0;
XColor rgbValue;

while (strlen(colorList[color]) != 0)
{ if (!XParseColor(display, colormap, colorList[color], &rgbValue))
{ printf("\n %d:%s was not in the database", color, colorList[color] );
}
else
{ if (!XAllocColor(display, colormap, &rgbValue))
printf("\n %d:%s could not be allocated",color,colorList[color]);
else rgb[colors++] = rgbValue.pixel;
}
color++;
}
return color;
}

/* Function to print error messages and abort. */

void error( Display *display, char *msg )
{ printf("\n\nmandelbrot:%s", msg);
if (display == NULL) exit(-1);
else
{ XFlush(display);
sleep(SLEEP_TIME);
XCloseDisplay(display);
exit(0);
} }

/* Main program logic */

int main(int argc, char *argv[])
{ char *windowName = "Mandelbrot Set";/* Name to display in title bar. */
char *displayName = NULL; /* Name of XWindow server. */
unsigned long rgbValues[MAX_COLORS];/* RGB allocated color array. */

Display *display; /* Information about server connection.*/
Window window; /* Structure for window. */
int screen; /* Number of default server screen. */
XSizeHints sizeHints; /* Preferred window size & position. */
XSetWindowAttributes attributes; /* Preferred window attributes. */
GC gc; /* Graphics context structure. */
int colors; /* Count of valid colors. */

int i, x, y, color; /* Temporary variables. */

/* Connect to XWindow server */

if ( (display = XOpenDisplay(displayName)) == NULL)
{ error(display, "Cannot connect to X server" );
}

/* Get default screen number controlled by the server */

screen = DefaultScreen(display);

/* Create window on the display, create the root window for this application */

window = XCreateSimpleWindow
(display, RootWindow(display,screen),0,0,WIDTH,HEIGHT,BORDER,
BlackPixel(display,screen), WhitePixel(display, screen));

/* Change window attributes so off display pixels are maintained. */

attributes.backing_store = Always;
attributes.backing_pixel = BlackPixel(display,screen);
XChangeWindowAttributes( display, window,
CWBackingStore | CWBackingPixel, &attributes);

/* Define preferences for window to be created */

sizeHints.flags = USPosition|USSize; /* Preferred window size & position.*/
sizeHints.x = 0;
sizeHints.y = 0;
sizeHints.width = WIDTH;
sizeHints.height = HEIGHT;
XSetNormalHints(display, window, &sizeHints);
XStoreName(display, window, windowName );

/* Create a graphics context
background and forground colors
the width/fill style/shape/join characteristics of pixels.
*/
gc = XCreateGC(display, RootWindow(display, screen), 0, NULL);
XSetForeground(display, gc, BlackPixel(display, screen));
XSetBackground(display, gc, WhitePixel(display, screen));
XSetLineAttributes(display, gc, 1, LineSolid, CapRound, JoinRound);

/* Map window so that it is displayed on the screen. */

XMapWindow(display, window);
XSync(display, 0);

/* Now we can test the colors. */

colors = verifyColors(display, screen, colorNames, rgbValues);
for (x=0; x<WIDTH; x++)
{ for (y=0; y<HEIGHT; y++)
{ color = (x*y+y) % colors;
XSetForeground(display, gc, rgbValues[color]);
XDrawPoint(display, window, gc, x, y );
} }
printf ("\n Number of Colors = %u\n", colors);
error(display, "Program Complete");
}