/*******************************************
 * Copyright (C) 1990 by Christopher R. Wren and 
 * the Massachusetts Institute of Technology
 *
 * COMMERCIAL DISCLAIMER:
 *
 * This software is intended for research purposes only and contains
 * unlicensed software, in original and modified forms, from various
 * sources including the Free Software Foundation.  These programs
 * shall not be used, rewritten, or adapted as the basis of a
 * commercial software or hardware product without first obtaining
 * appropriate licenses from the owners of the original software
 * copyrights.
 *
 * In the case of copyrighted software fragments obtained from the
 * Free Software Foundation: you can redistribute it and/or modify it
 * under the terms of the GNU Library General Public License as
 * published by the Free Software Foundation.  This software is
 * distributed in the hope that it will be useful, but WITHOUT ANY
 * WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Library General
 * Public License for more details.  You should have received a copy
 * of the GNU Library General Public License and the GNU General
 * Public License along with this software; if not, write to the Free
 * Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
 * 
 * Developed  by Christopher R. Wren at the 
 * Media Laboratory, MIT, Cambridge, Massachusetts.
 * 
 *******************************************/

#include <x.h>

XtAppContext context;
int color[256];
Widget simple;
GC gc;
Window win;
Display *dpy;

static String *fallback_resources = {
    NULL,
};


/*	Function Name: ConvertColor
 *	Description: This converts a string into a color.
 *	Arguments: color_name - name of the color.
 *	Returns: a pixel value for that color.
 */

static int
ConvertColor(w, color_name)
Widget w;
char * color_name;
{
  XrmValue from, to;

  from.size = strlen(color_name) + 1;  
  from.addr = color_name;

/*
 * This conversion accepts a colorname from rgb.txt, or a #rrrgggbbb 
 * rgb color definition, or the special toolkit strings "XtDefaultForeground" 
 * and "XtDefaultBackground".
 */

  XtConvert(w, XtRString, (XrmValuePtr) &from, XtRPixel, (XrmValuePtr) &to);
  if (to.addr == NULL) {
      return(-1);
  }

  return( (int) *((Pixel *) to.addr) );
}


void init_display(argc,argv,x,y)
     int     x;
     int     y;
     int    *argc;
     String *argv;
{
  Arg args[10];
  int nargs = 0;
  
  nargs = 0;
  XtSetArg(args[nargs],XtNwidth,x); nargs++;
  XtSetArg(args[nargs],XtNheight,y); nargs++;
  {
    Widget toplevel = XtAppInitialize(&context, "Fractals", NULL, 0,
				      argc, argv, fallback_resources, 
				      args,nargs);
    
    XtRealizeWidget(toplevel);
    
    dpy = XtDisplay(toplevel);
    
    {
      Colormap old;
      
      nargs = 0;
      XtSetArg(args[nargs],XtNcolormap,&old); nargs++;
      XtGetValues(toplevel,args,nargs);
      
      {
	Colormap new = XCopyColormapAndFree(dpy,old);
	
	{ 
	  char cname[100];
	  int i;
	  for (i=0; i<256 ; i++) {
	    int r = abs(((i + 120) % 256) - 127);
	    int g = abs(((i + 160) % 256) - 127);
	    int b = abs(((i + 200) % 256) - 127);
	    sprintf(cname,"#%02x%02x%02x",r,g,b);
	    if ((color[i] = ConvertColor(toplevel,cname)) < 0)
	      fprintf(stderr,"FAILED to alloc %s\n",cname);
	  }
	}

	nargs = 0;
	XtSetArg(args[nargs],XtNwidth,x); nargs++;
	XtSetArg(args[nargs],XtNheight,y); nargs++;
	XtSetArg(args[nargs],XtNcolormap,new); nargs++;
	
	simple = XtCreateManagedWidget("canvas", 
				       simpleWidgetClass, 
				       toplevel, 
				       args, nargs);
	
	win = XtWindow(simple);
	
	{
	  XGCValues gcv;
	  unsigned long gcm =0;
	  gc = XtGetGC(simple,gcm,&gcv);
	}
	
      }
    }
  }
}

void destroy_display()
{
  fprintf(stderr,"done\n");
  XtAppMainLoop(context);
}
  
void draw_pixel(c,x,y,s)
     int c,x,y,s;
{
  XSetForeground(dpy,gc,color[c%256]);
  XFillRectangle(dpy,win,gc,x,y,s,s);
}

void do_event()
{
  while(XtAppPending(context)) {
    XEvent event;
    XtAppNextEvent(context,&event);
    XtDispatchEvent(&event);
  }
}