/*
 * X11 (Unix X Window System) calls that feel useful for BW BASIC
 * from /usr/include/X11/Xlib.h - angles are in 1/64ths of degrees.
 * you may also have to include <X11/Xutil.h>.
 */

typedef struct {
    short x, y;
} XPoint;

/* for 16 bit depth you can use for example: */
typedef unsigned short int PIX;
#define RGB(r,g,b) (PIX) ( ((b) >> 3) | (((g) >> 2) << 5) | \
  (((r) >> 3) << 11) ) /* 565, low byte first assumed! */

/* To find the screen size and color depth: */
XGetGeometry( Display* display, Drawable d, Window* root_return,
  int* x_return, int* y_return, unsigned int* width_return,
  unsigned int* height_return, unsigned int* border_width_return,
  unsigned int* depth_return );

XCreateSimpleWindow( Display* display, Window parent, int x, int y,
  unsigned int width, unsigned int height, unsigned int border_width,
  unsigned long border, unsigned long background );

Display*  dis = XOpenDisplay  ( NULL );
if ( dis != NULL ) {
      disScreen = DefaultScreen ( dis );
      disDepth  = DefaultDepth  ( dis , disScreen );
      disWidth  = DisplayWidth  ( dis , disScreen );
      disHeight = DisplayHeight ( dis , disScreen );
}

Window winRoot = DefaultRootWindow ( dis );
Window myWindow = XCreateSimpleWindow( ... );
  XStoreName ( dis , win , "Name of your window" );
  XClearWindow ( dis , win );
  XMapRaised ( dis , win );
  XFlush ( dis );
/* you can use XCreateImage() to control a bitmap in the window... */

  XGCValues gcVal;
  gcVal.foreground = 0;     
  gcVal.background = 0;
  unsigned long gcMask = GCForeground | GCBackground;
  GC gc = XCreateGC ( dis , win , gcMask , &gcVal );

/* *** YOUR CODE HERE *** */

/* *** to update the display, use XPutImage() if you have *** */
/* *** changed the bitmap. Other drawing takes effect at  *** */
/* *** once but you can use XFlush(Display* display) or   *** */
/* *** wait using XSync(Display* display, Bool discard).  *** */
/* *** (discard should be false...)                       *** */

  XFreeGC        ( dis , gc );
  /* XDestroyImage  ( xim ); */
  XDestroyWindow ( dis , win );
  XCloseDisplay  ( dis );     


/* *** HAVE SOME DRAWING PRIMITIVES... HAVE FUN! *** */


XDrawLine( Display* display, Drawable d, GC gc,
  int x1, int x1, int y1, int y2 );

/* mode is either of CoordModeOrigin or CoordModePrevious */
XDrawLines( Display* display, Drawable d, GC gc,
  XPoint* points, int npoints, int mode );

XDrawRectangle(  Display* display, Drawable d, GC gc,
  int x, int y, unsigned int width, unsigned int height );

XDrawArc(  Display* display, Drawable d, GC gc,
  int x, int y, unsigned int width, unsigned int height,
  int angle1, int angle2 );

/* see also XSetFont(); 
XDrawString(  Display* display, Drawable d, GC gc,
  int x, int y, _Xconst char* string, int length );

XFillRectangle(  Display* display, Drawable d, GC gc,
  int x, int y, unsigned int width, unsigned int height );

XDrawPoint(  Display* display, Drawable d, GC gc,
  int x, int y );

XFillRectangle(  Display* display, Drawable d, GC gc,
  int x, int y, unsigned int width, unsigned int height );


XFillArc(  Display* display, Drawable d, GC gc,
  int x, int y, unsigned int width, unsigned int height,
  int angle1, int angle2 );

/* shape is either of Complex, Convex or Nonconvex. Use   */
/* complex if you are not sure and need no optimization.  */
/* mode is either of CoordModeOrigin or CoordModePrevious */
XFillPolygon(  Display* display, Drawable d, GC gc,
  XPoint* points, int npoints, int shape, int mode );

/* fill_style is either of FillSolid, FillTiles, FillStippled */
/* or FillOpaqueStippled... */
/* see also XSetStipple() XSetTile() XSetDashes() for lines */
XSetFillStyle( Display* display, GC gc, int fill_style );

XSetForeground( Display* display, GC gc, unsigned long foreground );

/* arc_mode is either of ArcChord, ArcPieSlice */
XSetArcMode( Display* display, GC gc, int arc_mode );

/* line_style is either of LineSolid, LineOnOffDash,    */
/* LineDoubleDash. cap_style is either of CapNotLast,   */
/* CapButt, CapRound, CapProjecting. join_style is      */
/* either of JoinMiter, JoinRound, JoinBevel.           */
XSetLineAttributes( Display* display, GC gc,
  unsigned int line_width, int line_style,
  int cap_style, int join_style );