Date: Fri, 18 Mar 1994 09:06:40 +0100 (MET)
From: Raul y Quique <nuevos AT hp400 DOT ccu DOT uniovi DOT es>
Subject: capture a screen using GRX & LUG
To: djgpp AT sun DOT soe DOT clarkson DOT edu
Cc: djgpp-bounces AT sun DOT soe DOT clarkson DOT edu


Yesterday, I received a mail about how to capture a screen using the GRX
and LUG libraries.

The target is something like:

        {
          bitmap_hdr bitmap;
	  ...
	  <here show what u wanna >
          ...
          if ( capture_GRX_bitmap( &bitmap ) != -1 ) {
            /* Fine !. Write it using LUG */
            write_lug_file( "<the_name>", &bitmap );
            /* Free memory */
            freebitmap( &bitmap );
          }
          ...  
          <what u wanna, close graphics and ...>
          ...
        }

Remember that the output file format will be fixed using the given file
name (else use 'ad hoc' functions: write_gif_file, write_tga_file, ...).

The new function is ...

=================

/*
 * This software is copyrighted as noted below.  It may be freely copied,
 * modified, and redistributed, provided that the copyright notice is
 * preserved on all copies.
 *
 * There is no warranty or other guarantee of fitness for this software,
 * it is provided solely "as is".  Bug reports or fixes may be sent
 * to the author, who may or may not act on them as he desires.
 *
 * You may not include this software in a program or other software product
 * without supplying the source, or without informing the end-user that the
 * source is available for no extra charge.
 *
 * If you modify this software, you should include a notice giving the
 * name of the person performing the modification, the date of modification,
 * and the reason for such modification.
 */
/*
 * capture_grx.c - capture the graphics image displayed using the GRX library.
 *
 * Author:      Raul Rivero
 *              Vicerrectorado de Estudiantes
 *              University of Oviedo
 * Date:        Thu Mar 17 1994
 * Copyright (c) 1994, Raul Rivero
 *
 */

#include <lug.h>
#include <lugfnts.h>
#include <grx.h>

capture_GRX_image( bitmap )
bitmap_hdr *bitmap;
{
  register int i;
  int numcolors;
  int raux, gaux, baux;
  byte *ptr;

  /*
   * Ooopppsss!, only 8 bitmap images. There is not an special reason but
   * i have a 256 graphics board.
   */
  if ( (numcolors = GrNumColors()) > 256 )
    return -1;

  /* Fill the image header */
  bitmap->xsize  = GrSizeX();
  bitmap->ysize  = GrSizeY();
  bitmap->depth  = no_bits(numcolors) + 1;
  bitmap->colors = numcolors;
  bitmap->magic  = LUGUSED;

  /* Alloc space for the color map ... */
  bitmap->cmap = (byte *) Malloc( numcolors * 3 );
  /* ... and get it ! */
  for ( i = 0, ptr = bitmap->cmap; i < numcolors; i++ ) {
    GrQueryColor( i, &raux, &gaux, &baux );
    *ptr++ = raux;
    *ptr++ = gaux;
    *ptr++ = baux;
  }

  /* Get more :-) memory (raster information) */
  bitmap->r = (byte *) Malloc( bitmap->xsize * bitmap->ysize );
  /* 
   * DJGPP maps the memory video from the 0xd0000000 address, 
   * so our image buffer is ...
   */
  bcopy( (byte *) 0xd0000000, bitmap->r, bitmap->xsize * bitmap->ysize );

  /* And ... voila! ... it's done */
  return 0;
}

=================

If someone can hack the routine to work with a true color board, please.

Cheers.

--
                     ===================================
                                 Raul Rivero
                        Vicerrectorado de Estudiantes
                            Universidad de Oviedo
                              Arguelles, 39, 2o.
                                33003 - Oviedo
                                    Spain
                      ---------------------------------
                          rivero AT pinon DOT ccu DOT uniovi DOT es
                      ---------------------------------
                        "Es muy duro ser romantica  y
                         ninfomana a la vez", Ariadna
                         Gil en el corto El Columpio.
                     ===================================