/*  %kw # %v    %n    %d    %t #                      */
/*  Version # 1    BMAPBITS.C    7-Aug-98    13:26:54 #   */

/* *************************************************** */
/*     METAGRAPHICS SOFTWARE CORPORATION (c) 1998      */
/*                                                     */
/*     BMAPBITS.C illustrates how to directly access   */
/*     the pixel data in an offscreen bitmap created   */
/*     in local conventional memory.                   */
/*                                                     */
/*     Demonstrates usage of CreateBitmap(),           */
/*     DestroyBitmap() and CopyBlit()                  */
/* *************************************************** */

#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


int  GrafixCard, GrafixInput;


void main( int argc, char *argv[] )
{

   int       i,j;
   int       scrnHeight;   // screen height
   int       scrnWidth;    // screen width
   rect      sR, fR;       // temp working rects
   grafPort *thePort;      // pointer to the screen port(/bitmap)
   grafPort *offscrPort;   // pointer to the offscreen port(/bitmap)
   grafMap  *offscrBitmap; // pointer to the offscreen bitmap
   Byte    **offscrRowTable; // ptr to table of ptrs to each raster line
   Byte     *pixelPtr;     // pointer to pixel data


   MetQuery( argc,argv );              // autodetect the graphics card
   i = InitGraphics( GrafixCard );     // init MetaWINDOW
   if ( i != 0 )
      GrInitErr( i );                  // display reason for error

   GetPort( &thePort );                // get pointer to the screen port
   scrnWidth  = thePort->portMap->pixWidth;
   scrnHeight = thePort->portMap->pixHeight;

   printf("\nLaunching offscreen local memory bitmap");


   // *** create a memory bitmap and port matching the screen ***
   // (we could create any size bitmap if we wanted)
   offscrPort = CreateBitmap( cMEMORY, scrnWidth, scrnHeight );

   if ( offscrPort == NULL ) {
      printf("ERROR: Unable to allocate offscreen bitmap\n");
      exit(1); // abort if CreateBitmap() fails
   }


   printf("\nNow drawing to offscreen bitmap...");

   printf(" Fill...");
   sR = offscrPort->portRect;
   PenColor( Red );
   BackColor( LtGray );
   FillRect( &sR, 30 );

   printf(" Frame...");
   fR = sR;
   fR.Xmax--;
   fR.Ymax--;
   PenColor( Green );
   FrameRect( &fR );

   printf(" Some lines...");
   PenColor( Blue );
   MoveTo( fR.Xmin, fR.Ymin );
   LineTo( fR.Xmax, fR.Ymax );
   MoveTo( fR.Xmax, fR.Ymin );
   LineTo( fR.Xmin, fR.Ymax );

   printf(" Some text...");
   PenColor( Black );
   MoveTo( 20,40 );           
   DrawString("Offscreen bitmaps are easy with CreateBitmap()!");

   printf("\nNow manually setting first byte of each raster line to 0xFF...");
   offscrBitmap = offscrPort->portMap;
   // for 4-plane, 16-color modes loop through each plane
   for ( j=0; j<offscrBitmap->pixPlanes; j++ )
      {   
      offscrRowTable = offscrBitmap->mapTable[j];
      // now loop through each raster line
      for ( i=0; i<offscrBitmap->pixHeight; i++ )
         {
         pixelPtr = offscrRowTable[i];  // get the address of the 1st pixel byte
        *pixelPtr = 0xFF;  // set the first pixel byte to 0xFF
         }
      }

   printf("\n\nReady to copy offscreen bitmap to the screen");
   printf("\n(press Return to continue)\n");
   getch();                // wait for a keypress
   

   SetPort( thePort );     // switch back to the screen
   SetDisplay( GrafPg0 );  // switch display to graphics mode
   PaintRect( &sR );       // fill screen with a different color

   // copy the memory bitmap to the screen bitmap
   CopyBlit( offscrPort, thePort,
            &offscrPort->portRect, &thePort->portRect );
   getch();                // wait for a keypress

   // free the offscreen bitmap
   DestroyBitmap( offscrPort );

   SetDisplay( TextPg0 );  // Switch to text mode
   i = QueryError();       // Show any MetaWINDOW detected errors
   printf("QueryError=%d/%d",i >> 7,i & 127);
   StopGraphics();
   exit(i);
}



#include "metquery.c"

/* End of File - BMAPBITS.C */