tmap.s

The source code of Doom legacy for windows

// Emacs style mode select   -*- C++ -*- 
//-----------------------------------------------------------------------------
//
// $Id: tmap.s,v 1.5 2000/09/28 20:57:18 bpereira Exp $
//
// Copyright (C) 1998-2000 by DooM Legacy Team.
//
// This program is free software; you can redistribute it and/or
// modify it under the terms of the GNU General Public License
// as published by the Free Software Foundation; either version 2
// of the License, or (at your option) any later version.
//
// This program 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 General Public License for more details.
//
//
// $Log: tmap.s,v $
// Revision 1.5  2000/09/28 20:57:18  bpereira
// no message
//
// Revision 1.4  2000/08/10 14:58:42  ydario
// OS/2 port
//
// Revision 1.3  2000/04/24 20:24:38  bpereira
// no message
//
// Revision 1.2  2000/02/27 00:42:11  hurdler
// fix CR+LF problem
//
// Revision 1.1.1.1  2000/02/22 20:32:32  hurdler
// Initial import into CVS (v1.29 pr3)
//
//
// DESCRIPTION:
//      optimised drawing routines for span/column rendering
//
//
//-----------------------------------------------------------------------------


// structures, must match the C structures!
#include "asm_defs.inc"


// Rappel: seuls EAX, ECX, EDX peuvent 阾re 閏ras閟 librement.
//         il faut sauver esi,edi, cd...gs

/* Attention aux comparaisons!                                              */
/*                                                                          */
/*      Intel_compare:                                                      */
/*                                                                          */
/*              cmp     A,B                     // A-B , set flags          */
/*              jg      A_greater_than_B                                    */
/*                                                                          */
/*      AT&T_compare:                                                       */
/*                                                                          */
/*              cmp     A,B                     // B-A , set flags          */
/*              jg      B_greater_than_A                                    */
/*                                                                          */
/*        (soustrait l'op閞ande source DE l'op閞ande destination,           */
/*         comme sur Motorola! )                                            */


// RAPPEL: Intel
//         SECTION:[BASE+INDEX*SCALE+DISP]
// devient SECTION:DISP(BASE,INDEX,SCALE)

//----------------------------------------------------------------------
//
// R_DrawColumn
//
//   New optimised version 10-01-1998 by D.Fabrice and P.Boris
//   TO DO: optimise it much farther... should take at most 3 cycles/pix
//          once it's fixed, add code to patch the offsets so that it
//          works in every screen width.
//
//----------------------------------------------------------------------

    .data
#ifdef LINUX
    .align 2
#else
    .align 4
#endif    
C(loopcount):   .long   0
C(pixelcount):  .long   0
C(tystep):      .long   0

C(vidwidth):    .long   0       //use this one out of the inner loops
                                //so you don't need to patch everywhere...

#ifdef USEASM
#if !defined( LINUX) && !defined( __OS2__)
    .text
#endif
.globl C(ASM_PatchRowBytes)
C(ASM_PatchRowBytes):
    pushl   %ebp
    movl    %esp, %ebp      // assure l'"adressabilit