/*  %kw # %v    %n    %d    %t # */
/* Version # 2    MW2PAGE.C    27-Oct-92    9:58:00 # */
/**********************************************************/
/*   METAGRAPHICS SOFTWARE CORPORATION (c) 1987-1992      */
/*                                                        */
/* Description: This program is an example of how to use  */
/*              and flip between the two EGA pages.       */
/*                                                        */
/* Functions used:                                        */
/* SetBitmap, SetDisplay                                  */
/**********************************************************/

#include <stdlib.h>
#include <stddef.h>
#include <stdio.h>
#include <string.h>
#include <conio.h>
#include <dos.h>
#include <ctype.h>
#include "metawndo.h"      /* master MetaWINDOW include file */

/* special stack size declaration if using Turbo or Borland C++ */
#ifdef      TurboC
extern unsigned _stklen = 14336U;  /* stack size 14K */
#endif


void scrn1(void);
rect  scrnR;


void main()
{
   int   i;
   rect ballR;
   grafPort *scrnport;

   i = InitGraphics( EGA640x350 );
   if( i != 0 ) {
      printf( "MetaWINDOW InitGraphics error - %d\n",i );
      exit(1);
   }

   /* do an initial setdisplay to put into graphics mode */
   SetDisplay( GrafPg0 ); 

   ScreenRect(&scrnR);           /* Get the screen limits       */
   EraseRect(&scrnR);            /* Clear the screen            */

   /* set a bounding rectangle for the ball */
   SetRect( &ballR, 0,((scrnR.Ymax/2) - 30), 32, scrnR.Ymax/2);
   OffsetRect( &ballR, scrnR.Xmax/4, 0);

   /* get pointer to current (default) port */
   GetPort( &scrnport );

   for (i=0; i<100; i++)
   {

      /* draw to bitmap page 0 */

      scrn1();                         /* draw background screen */
      OffsetRect( &ballR, 2, 0);       /* move the ball          */
      PenColor(5);
      FillOval( &ballR, 1);

      /* display bitmap page 0 */
      SetDisplay( GrafPg0); 

      /* draw to bitmap page 1 */
      SetBitmap(GrafPg1,scrnport->portMap);
      scrn1();                      /* draw background screen */
      OffsetRect( &ballR, 2, 0);       /* move the ball          */
      PenColor(5);
      FillOval( &ballR, 1);

      /* displaying bitmap page 1 */
      SetDisplay( GrafPg1);

      /* draw to bitmap page 0 */
      SetBitmap(GrafPg0,scrnport->portMap);
   }

   SetDisplay(TextPg0);     /* Switch to alpha mode        */

   StopGraphics();
   i = QueryError();
   printf("QueryError=%d/%d\n", i >> 7, i & 127);
   exit(i);
}


/* set-up "background" screen */
void scrn1()
{
   int wid,len,beg,half;
   int wallx, wally;

   wid = 10;
   len = 30;
   beg = scrnR.Xmax/4;
   half = scrnR.Ymax/2;
   wallx = beg - 70;
   wally = scrnR.Ymax/4;

   PenColor(0);
   EraseRect(&scrnR);
   PenColor(1);

   /* draw the bowling lane */
   MoveTo( (beg+len), (half - wid));         /* top lane line */
   LineTo( scrnR.Xmax, (half - wid));
   MoveTo( beg, (half + wid));          /* bottom lane line */
   LineTo( (scrnR.Xmax - len), (half + wid));

   MoveTo( (beg+len), (half - wid));         /* start line  */
   LineTo( beg, (half + wid));
   MoveTo( scrnR.Xmax, (half - wid)); /* finish line */
   LineTo( (scrnR.Xmax - len), (half + wid));

   MoveTo( (scrnR.Xmax - 80), (half - 3)); /* top of tri */
   LineTo( scrnR.Xmax, (half - wid)); 
   MoveTo( (scrnR.Xmax - 80), (half - 3)); /* bottom of tri */
   LineTo( (scrnR.Xmax - len), (half + wid));

   /* draw the bowling alley */
   MoveTo( wallx, wally); LineTo( wallx, 0);  
   MoveTo( wallx, wally); LineTo( scrnR.Xmax, wally);  
   MoveTo( wallx, wally); LineTo( 0, half - 50);  
   

}