mirror of
https://github.com/netwide-assembler/nasm.git
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1449 lines
42 KiB
NASM
1449 lines
42 KiB
NASM
;; NASM note: this file abuses the section flags in such a way that
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;; NASM 0.98.37 broke when this was compiled with:
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;; nasm -o tmap.o -f elf -DLINUX tmap.nas
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;;-----------------------------------------------------------------------------
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;;
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;; $Id$
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;;
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;; Copyright (C) 1998-2000 by DooM Legacy Team.
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;;
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;; This program is free software; you can redistribute it and/or
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;; modify it under the terms of the GNU General Public License
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;; as published by the Free Software Foundation; either version 2
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;; of the License, or (at your option) any later version.
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;;
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;; This program is distributed in the hope that it will be useful,
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;; but WITHOUT ANY WARRANTY; without even the implied warranty of
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;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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;; GNU General Public License for more details.
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;;
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;;
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;; $Log$
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;; Revision 1.2 2003/09/10 23:33:38 hpa
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;; Use the version of tmap.nas that actually caused problems
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;;
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;; Revision 1.10 2001/02/24 13:35:21 bpereira
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;; no message
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;;
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;; Revision 1.9 2001/02/10 15:24:19 hurdler
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;; Apply Rob's patch for Linux version
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;;
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;; Revision 1.8 2000/11/12 09:48:15 bpereira
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;; no message
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;;
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;; Revision 1.7 2000/11/06 20:52:16 bpereira
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;; no message
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;;
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;; Revision 1.6 2000/11/03 11:48:40 hurdler
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;; Fix compiling problem under win32 with 3D-Floors and FragglScript (to verify!)
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;;
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;; Revision 1.5 2000/11/03 03:27:17 stroggonmeth
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;; Again with the bug fixing...
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;;
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;; Revision 1.4 2000/11/02 17:50:10 stroggonmeth
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;; Big 3Dfloors & FraggleScript commit!!
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;;
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;; Revision 1.3 2000/04/24 20:24:38 bpereira
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;; no message
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;;
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;; Revision 1.2 2000/02/27 00:42:11 hurdler
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;; fix CR+LF problem
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;;
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;; Revision 1.1.1.1 2000/02/22 20:32:32 hurdler
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;; Initial import into CVS (v1.29 pr3)
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;;
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;;
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;; DESCRIPTION:
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;; assembler optimised rendering code for software mode
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;; draw floor spans, and wall columns.
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;;
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;;-----------------------------------------------------------------------------
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[BITS 32]
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%ifdef LINUX
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%macro cextern 1
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[extern %1]
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%endmacro
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%macro cglobal 1
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[global %1]
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%endmacro
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%define CODE_SEG .data
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%else
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%macro cextern 1
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%define %1 _%1
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[extern %1]
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%endmacro
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%macro cglobal 1
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%define %1 _%1
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[global %1]
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%endmacro
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%define CODE_SEG .text
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%endif
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;; externs
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;; columns
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cextern dc_x
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cextern dc_yl
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cextern dc_yh
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cextern ylookup
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cextern columnofs
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cextern dc_source
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cextern dc_texturemid
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cextern dc_iscale
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cextern centery
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cextern dc_colormap
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cextern dc_transmap
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cextern colormaps
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;; spans
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cextern ds_x1
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cextern ds_x2
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cextern ds_y
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cextern ds_xfrac
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cextern ds_yfrac
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cextern ds_xstep
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cextern ds_ystep
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cextern ds_source
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cextern ds_colormap
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;cextern ds_textureheight
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; polygon edge rasterizer
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cextern prastertab
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;;----------------------------------------------------------------------
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;;
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;; R_DrawColumn
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;;
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;; New optimised version 10-01-1998 by D.Fabrice and P.Boris
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;; TO DO: optimise it much farther... should take at most 3 cycles/pix
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;; once it's fixed, add code to patch the offsets so that it
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;; works in every screen width.
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;;
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;;----------------------------------------------------------------------
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[SECTION .data]
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;;.align 4
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loopcount dd 0
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pixelcount dd 0
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tystep dd 0
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[SECTION CODE_SEG write]
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;----------------------------------------------------------------------------
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;fixed_t FixedMul (fixed_t a, fixed_t b)
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;----------------------------------------------------------------------------
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cglobal FixedMul
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; align 16
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FixedMul:
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mov eax,[esp+4]
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imul dword [esp+8]
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shrd eax,edx,16
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ret
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;----------------------------------------------------------------------------
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;fixed_t FixedDiv2 (fixed_t a, fixed_t b);
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;----------------------------------------------------------------------------
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cglobal FixedDiv2
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; align 16
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FixedDiv2:
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mov eax,[esp+4]
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mov edx,eax ;; these two instructions allow the next
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sar edx,31 ;; two to pair, on the Pentium processor.
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shld edx,eax,16
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sal eax,16
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idiv dword [esp+8]
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ret
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;----------------------------------------------------------------------------
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; void ASM_PatchRowBytes (int rowbytes);
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;----------------------------------------------------------------------------
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cglobal ASM_PatchRowBytes
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; align 16
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ASM_PatchRowBytes:
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mov eax,[esp+4]
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mov [p1+2],eax
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mov [p2+2],eax
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mov [p3+2],eax
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mov [p4+2],eax
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mov [p5+2],eax
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mov [p6+2],eax
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mov [p7+2],eax
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mov [p8+2],eax
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mov [p9+2],eax
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mov [pa+2],eax
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mov [pb+2],eax
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mov [pc+2],eax
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mov [pd+2],eax
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mov [pe+2],eax
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mov [pf+2],eax
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mov [pg+2],eax
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mov [ph+2],eax
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mov [pi+2],eax
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mov [pj+2],eax
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mov [pk+2],eax
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mov [pl+2],eax
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mov [pm+2],eax
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mov [pn+2],eax
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mov [po+2],eax
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mov [pp+2],eax
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mov [pq+2],eax
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add eax,eax
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mov [q1+2],eax
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mov [q2+2],eax
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mov [q3+2],eax
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mov [q4+2],eax
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mov [q5+2],eax
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mov [q6+2],eax
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mov [q7+2],eax
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mov [q8+2],eax
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ret
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;----------------------------------------------------------------------------
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; 8bpp column drawer
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;----------------------------------------------------------------------------
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cglobal R_DrawColumn_8
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; align 16
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R_DrawColumn_8:
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push ebp ;; preserve caller's stack frame pointer
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push esi ;; preserve register variables
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push edi
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push ebx
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;;
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;; dest = ylookup[dc_yl] + columnofs[dc_x];
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;;
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mov ebp,[dc_yl]
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mov ebx,ebp
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mov edi,[ylookup+ebx*4]
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mov ebx,[dc_x]
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add edi,[columnofs+ebx*4] ;; edi = dest
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;;
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;; pixelcount = yh - yl + 1
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;;
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mov eax,[dc_yh]
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inc eax
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sub eax,ebp ;; pixel count
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mov [pixelcount],eax ;; save for final pixel
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jle near vdone ;; nothing to scale
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;;
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;; frac = dc_texturemid - (centery-dc_yl)*fracstep;
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;;
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mov ecx,[dc_iscale] ;; fracstep
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mov eax,[centery]
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sub eax,ebp
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imul eax,ecx
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mov edx,[dc_texturemid]
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sub edx,eax
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mov ebx,edx
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shr ebx,16 ;; frac int.
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and ebx,0x7f
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shl edx,16 ;; y frac up
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mov ebp,ecx
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shl ebp,16 ;; fracstep f. up
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shr ecx,16 ;; fracstep i. ->cl
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and cl,0x7f
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mov esi,[dc_source]
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;;
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;; lets rock :) !
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;;
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mov eax,[pixelcount]
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mov dh,al
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shr eax,2
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mov ch,al ;; quad count
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mov eax,[dc_colormap]
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test dh,0x3
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je near v4quadloop
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;;
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;; do un-even pixel
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;;
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test dh,0x1
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je two_uneven
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mov al,[esi+ebx] ;; prep un-even loops
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add edx,ebp ;; ypos f += ystep f
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adc bl,cl ;; ypos i += ystep i
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mov dl,[eax] ;; colormap texel
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and bl,0x7f ;; mask 0-127 texture index
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mov [edi],dl ;; output pixel
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p1: add edi,0x12345678
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;;
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;; do two non-quad-aligned pixels
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;;
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two_uneven:
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test dh,0x2
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je f3
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mov al,[esi+ebx] ;; fetch source texel
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add edx,ebp ;; ypos f += ystep f
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adc bl,cl ;; ypos i += ystep i
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mov dl,[eax] ;; colormap texel
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and bl,0x7f ;; mask 0-127 texture index
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mov [edi],dl ;; output pixel
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mov al,[esi+ebx]
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add edx,ebp ;; fetch source texel
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adc bl,cl ;; ypos f += ystep f
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mov dl,[eax] ;; ypos i += ystep i
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and bl,0x7f ;; colormap texel
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p2: add edi,0x12345678 ;; mask 0-127 texture index
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mov [edi],dl
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p3: add edi,0x12345678 ;; output pixel
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;;
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;; test if there was at least 4 pixels
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;;
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f3:
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test ch,0xff ;; test quad count
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je near vdone
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;;
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;; ebp : ystep frac. upper 16 bits
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;; edx : y frac. upper 16 bits
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;; ebx : y i. lower 7 bits, masked for index
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;; ecx : ch = counter, cl = y step i.
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;; eax : colormap aligned 256
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;; esi : source texture column
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;; edi : dest screen
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;;
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v4quadloop:
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mov dh,0x7f ;; prep mask
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align 4
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vquadloop:
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mov al,[esi+ebx] ;; prep loop
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add edx,ebp ;; ypos f += ystep f
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adc bl,cl ;; ypos i += ystep i
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mov dl,[eax] ;; colormap texel
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mov [edi],dl ;; output pixel
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and bl,0x7f ;; mask 0-127 texture index
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mov al,[esi+ebx] ;; fetch source texel
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add edx,ebp
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adc bl,cl
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p4: add edi,0x12345678
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mov dl,[eax]
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and bl,0x7f
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mov [edi],dl
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mov al,[esi+ebx] ;; fetch source texel
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add edx,ebp
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adc bl,cl
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p5: add edi,0x12345678
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mov dl,[eax]
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and bl,0x7f
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mov [edi],dl
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mov al,[esi+ebx] ;; fetch source texel
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add edx,ebp
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adc bl,cl
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p6: add edi,0x12345678
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mov dl,[eax]
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and bl,0x7f
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mov [edi],dl
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p7: add edi,0x12345678
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dec ch
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jne vquadloop
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||
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||
vdone:
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pop ebx ;; restore register variables
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||
pop edi
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pop esi
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pop ebp ;; restore caller's stack frame pointer
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ret
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|
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;;----------------------------------------------------------------------
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;;13-02-98:
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;; R_DrawSkyColumn : same as R_DrawColumn but:
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;;
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;; - wrap around 256 instead of 127.
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;; this is needed because we have a higher texture for mouselook,
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;; we need at least 200 lines for the sky.
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;;
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;; NOTE: the sky should never wrap, so it could use a faster method.
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;; for the moment, we'll still use a wrapping method...
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;;
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;; IT S JUST A QUICK CUT N PASTE, WAS NOT OPTIMISED AS IT SHOULD BE !!!
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;;
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;;----------------------------------------------------------------------
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cglobal R_DrawSkyColumn_8
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; align 16
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R_DrawSkyColumn_8:
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push ebp
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push esi
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push edi
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push ebx
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;;
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;; dest = ylookup[dc_yl] + columnofs[dc_x];
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;;
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mov ebp,[dc_yl]
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mov ebx,ebp
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mov edi,[ylookup+ebx*4]
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mov ebx,[dc_x]
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add edi,[columnofs+ebx*4] ;; edi = dest
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;;
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;; pixelcount = yh - yl + 1
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;;
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mov eax,[dc_yh]
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inc eax
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sub eax,ebp ;; pixel count
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mov [pixelcount],eax ;; save for final pixel
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jle near vskydone ;; nothing to scale
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;;
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;; frac = dc_texturemid - (centery-dc_yl)*fracstep;
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;;
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mov ecx,[dc_iscale] ;; fracstep
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mov eax,[centery]
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||
sub eax,ebp
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||
imul eax,ecx
|
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mov edx,[dc_texturemid]
|
||
sub edx,eax
|
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mov ebx,edx
|
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shr ebx,16 ;; frac int.
|
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and ebx,0xff
|
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shl edx,16 ;; y frac up
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mov ebp,ecx
|
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shl ebp,16 ;; fracstep f. up
|
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shr ecx,16 ;; fracstep i. ->cl
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mov esi,[dc_source]
|
||
;;
|
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;; lets rock :) !
|
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;;
|
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mov eax,[pixelcount]
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mov dh,al
|
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shr eax,0x2
|
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mov ch,al ;; quad count
|
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mov eax,[dc_colormap]
|
||
test dh,0x3
|
||
je vskyquadloop
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||
;;
|
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;; do un-even pixel
|
||
;;
|
||
test dh,0x1
|
||
je f2
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||
mov al,[esi+ebx] ;; prep un-even loops
|
||
add edx,ebp ;; ypos f += ystep f
|
||
adc bl,cl ;; ypos i += ystep i
|
||
mov dl,[eax] ;; colormap texel
|
||
mov [edi],dl ;; output pixel
|
||
p8: add edi,0x12345678
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||
;;
|
||
;; do two non-quad-aligned pixels
|
||
;;
|
||
f2: test dh,0x2
|
||
je skyf3
|
||
|
||
mov al,[esi+ebx] ;; fetch source texel
|
||
add edx,ebp ;; ypos f += ystep f
|
||
adc bl,cl ;; ypos i += ystep i
|
||
mov dl,[eax] ;; colormap texel
|
||
mov [edi],dl ;; output pixel
|
||
|
||
mov al,[esi+ebx] ;; fetch source texel
|
||
add edx,ebp ;; ypos f += ystep f
|
||
adc bl,cl ;; ypos i += ystep i
|
||
mov dl,[eax] ;; colormap texel
|
||
p9: add edi,0x12345678
|
||
mov [edi],dl ;; output pixel
|
||
|
||
pa: add edi,0x12345678
|
||
;;
|
||
;; test if there was at least 4 pixels
|
||
;;
|
||
skyf3: test ch,0xff ;; test quad count
|
||
je vskydone
|
||
;;
|
||
;; ebp : ystep frac. upper 24 bits
|
||
;; edx : y frac. upper 24 bits
|
||
;; ebx : y i. lower 7 bits, masked for index
|
||
;; ecx : ch = counter, cl = y step i.
|
||
;; eax : colormap aligned 256
|
||
;; esi : source texture column
|
||
;; edi : dest screen
|
||
;;
|
||
align 4
|
||
vskyquadloop:
|
||
mov al,[esi+ebx] ;; prep loop
|
||
add edx,ebp ;; ypos f += ystep f
|
||
mov dl,[eax] ;; colormap texel
|
||
adc bl,cl ;; ypos i += ystep i
|
||
mov [edi],dl ;; output pixel
|
||
|
||
mov al,[esi+ebx] ;; fetch source texel
|
||
add edx,ebp
|
||
adc bl,cl
|
||
pb: add edi,0x12345678
|
||
mov dl,[eax]
|
||
mov [edi],dl
|
||
|
||
mov al,[esi+ebx] ;; fetch source texel
|
||
add edx,ebp
|
||
adc bl,cl
|
||
pc: add edi,0x12345678
|
||
mov dl,[eax]
|
||
mov [edi],dl
|
||
|
||
mov al,[esi+ebx] ;; fetch source texel
|
||
add edx,ebp
|
||
adc bl,cl
|
||
pd: add edi,0x12345678
|
||
mov dl,[eax]
|
||
mov [edi],dl
|
||
|
||
pe: add edi,0x12345678
|
||
|
||
dec ch
|
||
jne vskyquadloop
|
||
vskydone:
|
||
pop ebx
|
||
pop edi
|
||
pop esi
|
||
pop ebp
|
||
ret
|
||
|
||
|
||
;;----------------------------------------------------------------------
|
||
;; R_DrawTranslucentColumn_8
|
||
;;
|
||
;; Vertical column texture drawer, with transparency. Replaces Doom2's
|
||
;; 'fuzz' effect, which was not so beautiful.
|
||
;; Transparency is always impressive in some way, don't know why...
|
||
;;----------------------------------------------------------------------
|
||
|
||
cglobal R_DrawTranslucentColumn_8
|
||
R_DrawTranslucentColumn_8:
|
||
push ebp ;; preserve caller's stack frame pointer
|
||
push esi ;; preserve register variables
|
||
push edi
|
||
push ebx
|
||
;;
|
||
;; dest = ylookup[dc_yl] + columnofs[dc_x];
|
||
;;
|
||
mov ebp,[dc_yl]
|
||
mov ebx,ebp
|
||
mov edi,[ylookup+ebx*4]
|
||
mov ebx,[dc_x]
|
||
add edi,[columnofs+ebx*4] ;; edi = dest
|
||
;;
|
||
;; pixelcount = yh - yl + 1
|
||
;;
|
||
mov eax,[dc_yh]
|
||
inc eax
|
||
sub eax,ebp ;; pixel count
|
||
mov [pixelcount],eax ;; save for final pixel
|
||
jle near vtdone ;; nothing to scale
|
||
;;
|
||
;; frac = dc_texturemid - (centery-dc_yl)*fracstep;
|
||
;;
|
||
mov ecx,[dc_iscale] ;; fracstep
|
||
mov eax,[centery]
|
||
sub eax,ebp
|
||
imul eax,ecx
|
||
mov edx,[dc_texturemid]
|
||
sub edx,eax
|
||
mov ebx,edx
|
||
|
||
shr ebx,16 ;; frac int.
|
||
and ebx,0x7f
|
||
shl edx,16 ;; y frac up
|
||
|
||
mov ebp,ecx
|
||
shl ebp,16 ;; fracstep f. up
|
||
shr ecx,16 ;; fracstep i. ->cl
|
||
and cl,0x7f
|
||
push cx
|
||
mov ecx,edx
|
||
pop cx
|
||
mov edx,[dc_colormap]
|
||
mov esi,[dc_source]
|
||
;;
|
||
;; lets rock :) !
|
||
;;
|
||
mov eax,[pixelcount]
|
||
shr eax,0x2
|
||
test byte [pixelcount],0x3
|
||
mov ch,al ;; quad count
|
||
mov eax,[dc_transmap]
|
||
je vt4quadloop
|
||
;;
|
||
;; do un-even pixel
|
||
;;
|
||
test byte [pixelcount],0x1
|
||
je trf2
|
||
|
||
mov ah,[esi+ebx] ;; fetch texel : colormap number
|
||
add ecx,ebp
|
||
adc bl,cl
|
||
mov al,[edi] ;; fetch dest : index into colormap
|
||
and bl,0x7f
|
||
mov dl,[eax]
|
||
mov dl,[edx]
|
||
mov [edi],dl
|
||
pf: add edi,0x12345678
|
||
;;
|
||
;; do two non-quad-aligned pixels
|
||
;;
|
||
trf2: test byte [pixelcount],0x2
|
||
je trf3
|
||
|
||
mov ah,[esi+ebx] ;; fetch texel : colormap number
|
||
add ecx,ebp
|
||
adc bl,cl
|
||
mov al,[edi] ;; fetch dest : index into colormap
|
||
and bl,0x7f
|
||
mov dl,[eax]
|
||
mov dl,[edx]
|
||
mov [edi],dl
|
||
pg: add edi,0x12345678
|
||
|
||
mov ah,[esi+ebx] ;; fetch texel : colormap number
|
||
add ecx,ebp
|
||
adc bl,cl
|
||
mov al,[edi] ;; fetch dest : index into colormap
|
||
and bl,0x7f
|
||
mov dl,[eax]
|
||
mov dl,[edx]
|
||
mov [edi],dl
|
||
ph: add edi,0x12345678
|
||
;;
|
||
;; test if there was at least 4 pixels
|
||
;;
|
||
trf3: test ch,0xff ;; test quad count
|
||
je near vtdone
|
||
|
||
;;
|
||
;; ebp : ystep frac. upper 24 bits
|
||
;; edx : y frac. upper 24 bits
|
||
;; ebx : y i. lower 7 bits, masked for index
|
||
;; ecx : ch = counter, cl = y step i.
|
||
;; eax : colormap aligned 256
|
||
;; esi : source texture column
|
||
;; edi : dest screen
|
||
;;
|
||
vt4quadloop:
|
||
mov ah,[esi+ebx] ;; fetch texel : colormap number
|
||
mov [tystep],ebp
|
||
pi: add edi,0x12345678
|
||
mov al,[edi] ;; fetch dest : index into colormap
|
||
pj: sub edi,0x12345678
|
||
mov ebp,edi
|
||
pk: sub edi,0x12345678
|
||
jmp short inloop
|
||
align 4
|
||
vtquadloop:
|
||
add ecx,[tystep]
|
||
adc bl,cl
|
||
q1: add ebp,0x23456789
|
||
and bl,0x7f
|
||
mov dl,[eax]
|
||
mov ah,[esi+ebx] ;; fetch texel : colormap number
|
||
mov dl,[edx]
|
||
mov [edi],dl
|
||
mov al,[ebp] ;; fetch dest : index into colormap
|
||
inloop:
|
||
add ecx,[tystep]
|
||
adc bl,cl
|
||
q2: add edi,0x23456789
|
||
and bl,0x7f
|
||
mov dl,[eax]
|
||
mov ah,[esi+ebx] ;; fetch texel : colormap number
|
||
mov dl,[edx]
|
||
mov [ebp+0x0],dl
|
||
mov al,[edi] ;; fetch dest : index into colormap
|
||
|
||
add ecx,[tystep]
|
||
adc bl,cl
|
||
q3: add ebp,0x23456789
|
||
and bl,0x7f
|
||
mov dl,[eax]
|
||
mov ah,[esi+ebx] ;; fetch texel : colormap number
|
||
mov dl,[edx]
|
||
mov [edi],dl
|
||
mov al,[ebp] ;; fetch dest : index into colormap
|
||
|
||
add ecx,[tystep]
|
||
adc bl,cl
|
||
q4: add edi,0x23456789
|
||
and bl,0x7f
|
||
mov dl,[eax]
|
||
mov ah,[esi+ebx] ;; fetch texel : colormap number
|
||
mov dl,[edx]
|
||
mov [ebp],dl
|
||
mov al,[edi] ;; fetch dest : index into colormap
|
||
|
||
dec ch
|
||
jne vtquadloop
|
||
vtdone:
|
||
pop ebx
|
||
pop edi
|
||
pop esi
|
||
pop ebp
|
||
ret
|
||
|
||
|
||
;;----------------------------------------------------------------------
|
||
;; R_DrawShadeColumn
|
||
;;
|
||
;; for smoke..etc.. test.
|
||
;;----------------------------------------------------------------------
|
||
cglobal R_DrawShadeColumn_8
|
||
R_DrawShadeColumn_8:
|
||
push ebp ;; preserve caller's stack frame pointer
|
||
push esi ;; preserve register variables
|
||
push edi
|
||
push ebx
|
||
|
||
;;
|
||
;; dest = ylookup[dc_yl] + columnofs[dc_x];
|
||
;;
|
||
mov ebp,[dc_yl]
|
||
mov ebx,ebp
|
||
mov edi,[ylookup+ebx*4]
|
||
mov ebx,[dc_x]
|
||
add edi,[columnofs+ebx*4] ;; edi = dest
|
||
;;
|
||
;; pixelcount = yh - yl + 1
|
||
;;
|
||
mov eax,[dc_yh]
|
||
inc eax
|
||
sub eax,ebp ;; pixel count
|
||
mov [pixelcount],eax ;; save for final pixel
|
||
jle near shdone ;; nothing to scale
|
||
;;
|
||
;; frac = dc_texturemid - (centery-dc_yl)*fracstep;
|
||
;;
|
||
mov ecx,[dc_iscale] ;; fracstep
|
||
mov eax,[centery]
|
||
sub eax,ebp
|
||
imul eax,ecx
|
||
mov edx,[dc_texturemid]
|
||
sub edx,eax
|
||
mov ebx,edx
|
||
shr ebx,16 ;; frac int.
|
||
and ebx,byte +0x7f
|
||
shl edx,16 ;; y frac up
|
||
|
||
mov ebp,ecx
|
||
shl ebp,16 ;; fracstep f. up
|
||
shr ecx,16 ;; fracstep i. ->cl
|
||
and cl,0x7f
|
||
|
||
mov esi,[dc_source]
|
||
;;
|
||
;; lets rock :) !
|
||
;;
|
||
mov eax,[pixelcount]
|
||
mov dh,al
|
||
shr eax,2
|
||
mov ch,al ;; quad count
|
||
mov eax,[colormaps]
|
||
test dh,3
|
||
je sh4quadloop
|
||
;;
|
||
;; do un-even pixel
|
||
;;
|
||
test dh,0x1
|
||
je shf2
|
||
|
||
mov ah,[esi+ebx] ;; fetch texel : colormap number
|
||
add edx,ebp
|
||
adc bl,cl
|
||
mov al,[edi] ;; fetch dest : index into colormap
|
||
and bl,0x7f
|
||
mov dl,[eax]
|
||
mov [edi],dl
|
||
pl: add edi,0x12345678
|
||
;;
|
||
;; do two non-quad-aligned pixels
|
||
;;
|
||
shf2:
|
||
test dh,0x2
|
||
je shf3
|
||
|
||
mov ah,[esi+ebx] ;; fetch texel : colormap number
|
||
add edx,ebp
|
||
adc bl,cl
|
||
mov al,[edi] ;; fetch dest : index into colormap
|
||
and bl,0x7f
|
||
mov dl,[eax]
|
||
mov [edi],dl
|
||
pm: add edi,0x12345678
|
||
|
||
mov ah,[esi+ebx] ;; fetch texel : colormap number
|
||
add edx,ebp
|
||
adc bl,cl
|
||
mov al,[edi] ;; fetch dest : index into colormap
|
||
and bl,0x7f
|
||
mov dl,[eax]
|
||
mov [edi],dl
|
||
pn: add edi,0x12345678
|
||
;;
|
||
;; test if there was at least 4 pixels
|
||
;;
|
||
shf3:
|
||
test ch,0xff ;; test quad count
|
||
je near shdone
|
||
|
||
;;
|
||
;; ebp : ystep frac. upper 24 bits
|
||
;; edx : y frac. upper 24 bits
|
||
;; ebx : y i. lower 7 bits, masked for index
|
||
;; ecx : ch = counter, cl = y step i.
|
||
;; eax : colormap aligned 256
|
||
;; esi : source texture column
|
||
;; edi : dest screen
|
||
;;
|
||
sh4quadloop:
|
||
mov dh,0x7f ;; prep mask
|
||
mov ah,[esi+ebx] ;; fetch texel : colormap number
|
||
mov [tystep],ebp
|
||
po: add edi,0x12345678
|
||
mov al,[edi] ;; fetch dest : index into colormap
|
||
pp: sub edi,0x12345678
|
||
mov ebp,edi
|
||
pq: sub edi,0x12345678
|
||
jmp short shinloop
|
||
|
||
align 4
|
||
shquadloop:
|
||
add edx,[tystep]
|
||
adc bl,cl
|
||
and bl,dh
|
||
q5: add ebp,0x12345678
|
||
mov dl,[eax]
|
||
mov ah,[esi+ebx] ;; fetch texel : colormap number
|
||
mov [edi],dl
|
||
mov al,[ebp] ;; fetch dest : index into colormap
|
||
shinloop:
|
||
add edx,[tystep]
|
||
adc bl,cl
|
||
and bl,dh
|
||
q6: add edi,0x12345678
|
||
mov dl,[eax]
|
||
mov ah,[esi+ebx] ;; fetch texel : colormap number
|
||
mov [ebp],dl
|
||
mov al,[edi] ;; fetch dest : index into colormap
|
||
|
||
add edx,[tystep]
|
||
adc bl,cl
|
||
and bl,dh
|
||
q7: add ebp,0x12345678
|
||
mov dl,[eax]
|
||
mov ah,[esi+ebx] ;; fetch texel : colormap number
|
||
mov [edi],dl
|
||
mov al,[ebp] ;; fetch dest : index into colormap
|
||
|
||
add edx,[tystep]
|
||
adc bl,cl
|
||
and bl,dh
|
||
q8: add edi,0x12345678
|
||
mov dl,[eax]
|
||
mov ah,[esi+ebx] ;; fetch texel : colormap number
|
||
mov [ebp],dl
|
||
mov al,[edi] ;; fetch dest : index into colormap
|
||
|
||
dec ch
|
||
jne shquadloop
|
||
|
||
shdone:
|
||
pop ebx ;; restore register variables
|
||
pop edi
|
||
pop esi
|
||
pop ebp ;; restore caller's stack frame pointer
|
||
ret
|
||
|
||
|
||
|
||
;;----------------------------------------------------------------------
|
||
;;
|
||
;; R_DrawSpan
|
||
;;
|
||
;; Horizontal texture mapping
|
||
;;
|
||
;;----------------------------------------------------------------------
|
||
|
||
|
||
[SECTION .data]
|
||
|
||
oldcolormap dd 0
|
||
|
||
[SECTION CODE_SEG write]
|
||
|
||
cglobal R_DrawSpan_8
|
||
R_DrawSpan_8:
|
||
push ebp ;; preserve caller's stack frame pointer
|
||
push esi ;; preserve register variables
|
||
push edi
|
||
push ebx
|
||
;;
|
||
;; initilise registers
|
||
;;
|
||
|
||
mov edx, [ds_xfrac]
|
||
mov eax, [ds_ystep]
|
||
ror edx, 14
|
||
ror eax, 15
|
||
mov bl, dl
|
||
mov ecx, [ds_xstep]
|
||
mov dh, al
|
||
mov ax, 1
|
||
mov [tystep], eax
|
||
|
||
|
||
mov eax, [ds_yfrac]
|
||
ror ecx, 13
|
||
ror eax, 16
|
||
mov dl, cl
|
||
mov bh, al
|
||
xor cx, cx
|
||
and ebx, 0x3fff
|
||
mov [pixelcount],ecx
|
||
|
||
mov ecx, [ds_x2]
|
||
mov edi, [ds_y]
|
||
mov esi, [ds_x1]
|
||
mov edi, [ylookup+edi*4]
|
||
mov ebp, ebx
|
||
add edi, [columnofs+esi*4]
|
||
sub esi, ecx ;; pixel count
|
||
shr ebp, 2
|
||
mov ecx, [ds_colormap]
|
||
mov ax, si
|
||
mov esi, [ds_source]
|
||
sar ax,1
|
||
jnc near .midloop ;; check parity
|
||
|
||
; summary
|
||
; edx = high16bit xfrac[0..13], ah=ystep[16..24] al=xtep[14..21]
|
||
; ebx = high16bit =0, bh=yfrac[16..24], bl=xfrac[14..21]
|
||
; ecx = colormap table cl=0 (colormap is aligned 8 bits)
|
||
; eax = high16bit yfrac[0..15], dx = count
|
||
; esi = flat texture source
|
||
; edi = screeen buffer destination
|
||
; ebp = work register
|
||
; pixelcount = high16bit xstep[0..13] rest to 0
|
||
; tystep = high16bit ystep[0..15] low 16 bit = 2 (increment of count)
|
||
|
||
align 4
|
||
.loop
|
||
add eax, [tystep]
|
||
mov cl, [esi+ebp]
|
||
adc bh, dh
|
||
mov cl, [ecx]
|
||
and bh, 0x3f
|
||
mov [edi], cl
|
||
mov ebp, ebx
|
||
inc edi
|
||
shr ebp, 2
|
||
|
||
.midloop:
|
||
add edx, [pixelcount]
|
||
mov cl, [esi+ebp]
|
||
adc bl, dl
|
||
mov cl, [ecx]
|
||
mov ebp, ebx
|
||
mov [edi], cl
|
||
inc edi
|
||
shr ebp, 2
|
||
|
||
test eax, 0xffff
|
||
jnz near .loop
|
||
|
||
.hdone: pop ebx ;; restore register variables
|
||
pop edi
|
||
pop esi
|
||
pop ebp ;; restore caller's stack frame pointer
|
||
ret
|
||
|
||
|
||
[SECTION .data]
|
||
|
||
obelix dd 0
|
||
etaussi dd 0
|
||
|
||
[SECTION CODE_SEG]
|
||
|
||
cglobal R_DrawSpan_8_old
|
||
R_DrawSpan_8_old:
|
||
push ebp ;; preserve caller's stack frame pointer
|
||
push esi ;; preserve register variables
|
||
push edi
|
||
push ebx
|
||
;;
|
||
;; find loop count
|
||
;;
|
||
mov eax,[ds_x2]
|
||
inc eax
|
||
sub eax,[ds_x1] ;; pixel count
|
||
mov [pixelcount],eax ;; save for final pixel
|
||
js near .hdone ;; nothing to scale
|
||
shr eax,0x1 ;; double pixel count
|
||
mov [loopcount],eax
|
||
;;
|
||
;; build composite position
|
||
;;
|
||
mov ebp,[ds_xfrac]
|
||
shl ebp,10
|
||
and ebp,0xffff0000
|
||
mov eax,[ds_yfrac]
|
||
shr eax,6
|
||
and eax,0xffff
|
||
mov edi,[ds_y]
|
||
or ebp,eax
|
||
|
||
mov esi,[ds_source]
|
||
;;
|
||
;; calculate screen dest
|
||
;;
|
||
mov edi,[ylookup+edi*4]
|
||
mov eax,[ds_x1]
|
||
add edi,[columnofs+eax*4]
|
||
;;
|
||
;; build composite step
|
||
;;
|
||
mov ebx,[ds_xstep]
|
||
shl ebx,10
|
||
and ebx,0xffff0000
|
||
mov eax,[ds_ystep]
|
||
shr eax,6
|
||
and eax,0xffff
|
||
or ebx,eax
|
||
|
||
mov [obelix],ebx
|
||
mov [etaussi],esi
|
||
|
||
;; %eax aligned colormap
|
||
;; %ebx aligned colormap
|
||
;; %ecx,%edx scratch
|
||
;; %esi virtual source
|
||
;; %edi moving destination pointer
|
||
;; %ebp frac
|
||
|
||
mov eax,[ds_colormap]
|
||
mov ecx,ebp
|
||
add ebp,ebx ;; advance frac pointer
|
||
shr cx,10
|
||
rol ecx,6
|
||
and ecx,4095 ;; finish calculation for third pixel
|
||
mov edx,ebp
|
||
shr dx,10
|
||
rol edx,6
|
||
add ebp,ebx ;; advance frac pointer
|
||
and edx,4095 ;; finish calculation for fourth pixel
|
||
mov ebx,eax
|
||
mov al,[esi+ecx] ;; get first pixel
|
||
mov bl,[esi+edx] ;; get second pixel
|
||
|
||
test dword [pixelcount],0xfffffffe
|
||
|
||
mov dl,[eax] ;; color translate first pixel
|
||
|
||
;; movw $0xf0f0,%dx ;;see visplanes start
|
||
|
||
je .hchecklast
|
||
|
||
mov dh,[ebx] ;; color translate second pixel
|
||
mov esi,[loopcount]
|
||
align 4
|
||
.hdoubleloop:
|
||
mov ecx,ebp
|
||
shr cx,10
|
||
rol ecx,6
|
||
add ebp,[obelix] ;; advance frac pointer
|
||
mov [edi],dx ;; write first pixel
|
||
and ecx,4095 ;; finish calculation for third pixel
|
||
mov edx,ebp
|
||
shr dx,10
|
||
rol edx,6
|
||
add ecx,[etaussi]
|
||
and edx,4095 ;; finish calculation for fourth pixel
|
||
mov al,[ecx] ;; get third pixel
|
||
add ebp,[obelix] ;; advance frac pointer
|
||
add edx,[etaussi]
|
||
mov bl,[edx] ;; get fourth pixel
|
||
mov dl,[eax] ;; color translate third pixel
|
||
add edi,byte +0x2 ;; advance to third pixel destination
|
||
dec esi ;; done with loop?
|
||
mov dh,[ebx] ;; color translate fourth pixel
|
||
jne .hdoubleloop
|
||
;; check for final pixel
|
||
.hchecklast:
|
||
test dword [pixelcount],0x1
|
||
je .hdone
|
||
mov [edi],dl ;; write final pixel
|
||
.hdone: pop ebx ;; restore register variables
|
||
pop edi
|
||
pop esi
|
||
pop ebp ;; restore caller's stack frame pointer
|
||
ret
|
||
|
||
|
||
;; ========================================================================
|
||
;; Rasterization des segments d'un polyg<79>ne textur<75> de mani<6E>re LINEAIRE.
|
||
;; Il s'agit donc d'interpoler les coordonn<6E>es aux bords de la texture en
|
||
;; m<>me temps que les abscisses minx/maxx pour chaque ligne.
|
||
;; L'argument 'dir' indique quels bords de la texture sont interpol<6F>s:
|
||
;; 0 : segments associ<63>s aux bord SUPERIEUR et INFERIEUR ( TY constant )
|
||
;; 1 : segments associ<63>s aux bord GAUCHE et DROITE ( TX constant )
|
||
;; ========================================================================
|
||
;;
|
||
;; void rasterize_segment_tex( LONG x1, LONG y1, LONG x2, LONG y2, LONG tv1, LONG tv2, LONG tc, LONG dir );
|
||
;; ARG1 ARG2 ARG3 ARG4 ARG5 ARG6 ARG7 ARG8
|
||
;;
|
||
;; Pour dir = 0, (tv1,tv2) = (tX1,tX2), tc = tY, en effet TY est constant.
|
||
;;
|
||
;; Pour dir = 1, (tv1,tv2) = (tY1,tY2), tc = tX, en effet TX est constant.
|
||
;;
|
||
;;
|
||
;; Uses: extern struct rastery *_rastertab;
|
||
;;
|
||
|
||
[SECTION CODE_SEG write]
|
||
|
||
MINX EQU 0
|
||
MAXX EQU 4
|
||
TX1 EQU 8
|
||
TY1 EQU 12
|
||
TX2 EQU 16
|
||
TY2 EQU 20
|
||
RASTERY_SIZEOF EQU 24
|
||
|
||
cglobal rasterize_segment_tex
|
||
rasterize_segment_tex:
|
||
push ebp
|
||
mov ebp,esp
|
||
|
||
sub esp,byte +0x8 ;; alloue les variables locales
|
||
|
||
push ebx
|
||
push esi
|
||
push edi
|
||
o16 mov ax,es
|
||
push eax
|
||
|
||
;; #define DX [ebp-4]
|
||
;; #define TD [ebp-8]
|
||
|
||
mov eax,[ebp+0xc] ;; y1
|
||
mov ebx,[ebp+0x14] ;; y2
|
||
cmp ebx,eax
|
||
je near .L_finished ;; special (y1==y2) segment horizontal, exit!
|
||
|
||
jg near .L_rasterize_right
|
||
|
||
;;rasterize_left: ;; on rasterize un segment <20> la GAUCHE du polyg<79>ne
|
||
|
||
mov ecx,eax
|
||
sub ecx,ebx
|
||
inc ecx ;; y1-y2+1
|
||
|
||
mov eax,RASTERY_SIZEOF
|
||
mul ebx ;; * y2
|
||
mov esi,[prastertab]
|
||
add esi,eax ;; point into rastertab[y2]
|
||
|
||
mov eax,[ebp+0x8] ;; ARG1
|
||
sub eax,[ebp+0x10] ;; ARG3
|
||
shl eax,0x10 ;; ((x1-x2)<<PRE) ...
|
||
cdq
|
||
idiv ecx ;; dx = ... / (y1-y2+1)
|
||
mov [ebp-0x4],eax ;; DX
|
||
|
||
mov eax,[ebp+0x18] ;; ARG5
|
||
sub eax,[ebp+0x1c] ;; ARG6
|
||
shl eax,0x10
|
||
cdq
|
||
idiv ecx ;; tdx =((tx1-tx2)<<PRE) / (y1-y2+1)
|
||
mov [ebp-0x8],eax ;; idem tdy =((ty1-ty2)<<PRE) / (y1-y2+1)
|
||
|
||
mov eax,[ebp+0x10] ;; ARG3
|
||
shl eax,0x10 ;; x = x2<<PRE
|
||
|
||
mov ebx,[ebp+0x1c] ;; ARG6
|
||
shl ebx,0x10 ;; tx = tx2<<PRE d0
|
||
;; ty = ty2<<PRE d1
|
||
mov edx,[ebp+0x20] ;; ARG7
|
||
shl edx,0x10 ;; ty = ty<<PRE d0
|
||
;; tx = tx<<PRE d1
|
||
push ebp
|
||
mov edi,[ebp-0x4] ;; DX
|
||
cmp dword [ebp+0x24],byte +0x0 ;; ARG8 direction ?
|
||
|
||
mov ebp,[ebp-0x8] ;; TD
|
||
je .L_rleft_h_loop
|
||
;;
|
||
;; TY varie, TX est constant
|
||
;;
|
||
.L_rleft_v_loop:
|
||
mov [esi+MINX],eax ;; rastertab[y].minx = x
|
||
add ebx,ebp
|
||
mov [esi+TX1],edx ;; .tx1 = tx
|
||
add eax,edi
|
||
mov [esi+TY1],ebx ;; .ty1 = ty
|
||
|
||
;;addl DX, %eax // x += dx
|
||
;;addl TD, %ebx // ty += tdy
|
||
|
||
add esi,RASTERY_SIZEOF ;; next raster line into rastertab[]
|
||
dec ecx
|
||
jne .L_rleft_v_loop
|
||
pop ebp
|
||
jmp .L_finished
|
||
;;
|
||
;; TX varie, TY est constant
|
||
;;
|
||
.L_rleft_h_loop:
|
||
mov [esi+MINX],eax ;; rastertab[y].minx = x
|
||
add eax,edi
|
||
mov [esi+TX1],ebx ;; .tx1 = tx
|
||
add ebx,ebp
|
||
mov [esi+TY1],edx ;; .ty1 = ty
|
||
|
||
;;addl DX, %eax // x += dx
|
||
;;addl TD, %ebx // tx += tdx
|
||
|
||
add esi,RASTERY_SIZEOF ;; next raster line into rastertab[]
|
||
dec ecx
|
||
jne .L_rleft_h_loop
|
||
pop ebp
|
||
jmp .L_finished
|
||
;;
|
||
;; on rasterize un segment <20> la DROITE du polyg<79>ne
|
||
;;
|
||
.L_rasterize_right:
|
||
mov ecx,ebx
|
||
sub ecx,eax
|
||
inc ecx ;; y2-y1+1
|
||
|
||
mov ebx,RASTERY_SIZEOF
|
||
mul ebx ;; * y1
|
||
mov esi,[prastertab]
|
||
add esi,eax ;; point into rastertab[y1]
|
||
|
||
mov eax,[ebp+0x10] ;; ARG3
|
||
sub eax,[ebp+0x8] ;; ARG1
|
||
shl eax,0x10 ;; ((x2-x1)<<PRE) ...
|
||
cdq
|
||
idiv ecx ;; dx = ... / (y2-y1+1)
|
||
mov [ebp-0x4],eax ;; DX
|
||
|
||
mov eax,[ebp+0x1c] ;; ARG6
|
||
sub eax,[ebp+0x18] ;; ARG5
|
||
shl eax,0x10
|
||
cdq
|
||
idiv ecx ;; tdx =((tx2-tx1)<<PRE) / (y2-y1+1)
|
||
mov [ebp-0x8],eax ;; idem tdy =((ty2-ty1)<<PRE) / (y2-y1+1)
|
||
|
||
mov eax,[ebp+0x8] ;; ARG1
|
||
shl eax,0x10 ;; x = x1<<PRE
|
||
|
||
mov ebx,[ebp+0x18] ;; ARG5
|
||
shl ebx,0x10 ;; tx = tx1<<PRE d0
|
||
;; ty = ty1<<PRE d1
|
||
mov edx,[ebp+0x20] ;; ARG7
|
||
shl edx,0x10 ;; ty = ty<<PRE d0
|
||
;; tx = tx<<PRE d1
|
||
push ebp
|
||
mov edi,[ebp-0x4] ;; DX
|
||
|
||
cmp dword [ebp+0x24], 0 ;; direction ?
|
||
|
||
mov ebp,[ebp-0x8] ;; TD
|
||
je .L_rright_h_loop
|
||
;;
|
||
;; TY varie, TX est constant
|
||
;;
|
||
.L_rright_v_loop:
|
||
|
||
mov [esi+MAXX],eax ;; rastertab[y].maxx = x
|
||
add ebx,ebp
|
||
mov [esi+TX2],edx ;; .tx2 = tx
|
||
add eax,edi
|
||
mov [esi+TY2],ebx ;; .ty2 = ty
|
||
|
||
;;addl DX, %eax // x += dx
|
||
;;addl TD, %ebx // ty += tdy
|
||
|
||
add esi,RASTERY_SIZEOF
|
||
dec ecx
|
||
jne .L_rright_v_loop
|
||
|
||
pop ebp
|
||
|
||
jmp short .L_finished
|
||
;;
|
||
;; TX varie, TY est constant
|
||
;;
|
||
.L_rright_h_loop:
|
||
mov [esi+MAXX],eax ;; rastertab[y].maxx = x
|
||
add eax,edi
|
||
mov [esi+TX2],ebx ;; .tx2 = tx
|
||
add ebx,ebp
|
||
mov [esi+TY2],edx ;; .ty2 = ty
|
||
|
||
;;addl DX, %eax // x += dx
|
||
;;addl TD, %ebx // tx += tdx
|
||
|
||
add esi,RASTERY_SIZEOF
|
||
dec ecx
|
||
jne .L_rright_h_loop
|
||
|
||
pop ebp
|
||
|
||
.L_finished:
|
||
pop eax
|
||
o16 mov es,ax
|
||
pop edi
|
||
pop esi
|
||
pop ebx
|
||
|
||
mov esp,ebp
|
||
pop ebp
|
||
ret
|
||
|
||
|
||
;;; this version can draw 64x64 tiles, but they would have to be arranged 4 per row,
|
||
;; so that the stride from one line to the next is 256
|
||
;;
|
||
;; .data
|
||
;;xstep dd 0
|
||
;;ystep dd 0
|
||
;;texwidth dd 64 ;; texture width
|
||
;; .text
|
||
;; this code is kept in case we add high-detail floor textures for example (256x256)
|
||
; align 16
|
||
;_R_DrawSpan_8:
|
||
; push ebp ;; preserve caller's stack frame pointer
|
||
; push esi ;; preserve register variables
|
||
; push edi
|
||
; push ebx
|
||
;;
|
||
;; find loop count
|
||
;;
|
||
; mov eax,[ds_x2]
|
||
; inc eax
|
||
; sub eax,[ds_x1] ;; pixel count
|
||
; mov [pixelcount],eax ;; save for final pixel
|
||
; js near .hdone ;; nothing to scale
|
||
;;
|
||
;; calculate screen dest
|
||
;;
|
||
; mov edi,[ds_y]
|
||
; mov edi,[ylookup+edi*4]
|
||
; mov eax,[ds_x1]
|
||
; add edi,[columnofs+eax*4]
|
||
;;
|
||
;; prepare registers for inner loop
|
||
;;
|
||
; xor eax,eax
|
||
; mov edx,[ds_xfrac]
|
||
; ror edx,16
|
||
; mov al,dl
|
||
; mov ecx,[ds_yfrac]
|
||
; ror ecx,16
|
||
; mov ah,cl
|
||
;
|
||
; mov ebx,[ds_xstep]
|
||
; ror ebx,16
|
||
; mov ch,bl
|
||
; and ebx,0xffff0000
|
||
; mov [xstep],ebx
|
||
; mov ebx,[ds_ystep]
|
||
; ror ebx,16
|
||
; mov dh,bl
|
||
; and ebx,0xffff0000
|
||
; mov [ystep],ebx
|
||
;
|
||
; mov esi,[ds_source]
|
||
;
|
||
;;; %eax Yi,Xi in %ah,%al
|
||
;;; %ebx aligned colormap
|
||
;;; %ecx Yfrac upper, dXi in %ch, %cl is counter (upto 1024pels, =4x256)
|
||
;;; %edx Xfrac upper, dYi in %dh, %dl receives mapped pixels from (ebx)
|
||
;;; ystep dYfrac, add to %ecx, low word is 0
|
||
;;; xstep dXfrac, add to %edx, low word is 0
|
||
;;; %ebp temporary register serves as offset like %eax
|
||
;;; %esi virtual source
|
||
;;; %edi moving destination pointer
|
||
;
|
||
; mov ebx,[pixelcount]
|
||
; shr ebx,0x2 ;; 4 pixels per loop
|
||
; test bl,0xff
|
||
; je near .hchecklast
|
||
; mov cl,bl
|
||
;
|
||
; mov ebx,[dc_colormap]
|
||
;;;
|
||
;;; prepare loop with first pixel
|
||
;;;
|
||
; add ecx,[ystep] ;;pr<70>a1
|
||
; adc ah,dh
|
||
; add edx,[xstep]
|
||
; adc al,ch
|
||
; and eax,0x3f3f
|
||
; mov bl,[esi+eax] ;;pr<70>b1
|
||
; mov dl,[ebx] ;;pr<70>c1
|
||
;
|
||
; add ecx,[ystep] ;;a2
|
||
; adc ah,dh
|
||
;
|
||
;.hdoubleloop:
|
||
; mov [edi+1],dl
|
||
; add edx,[xstep]
|
||
; adc al,ch
|
||
; add edi,byte +0x2
|
||
; mov ebp,eax
|
||
; add ecx,[ystep]
|
||
; adc ah,dh
|
||
; and ebp,0x3f3f
|
||
; add edx,[xstep]
|
||
; mov bl,[esi+ebp]
|
||
; adc al,ch
|
||
; mov dl,[ebx]
|
||
; and eax,0x3f3f
|
||
; mov [edi],dl
|
||
; mov bl,[esi+eax]
|
||
; add ecx,[ystep]
|
||
; adc ah,dh
|
||
; add edx,[xstep]
|
||
; adc al,ch
|
||
; mov dl,[ebx]
|
||
; mov ebp,eax
|
||
; mov [edi+1],dl
|
||
; and ebp,0x3f3f
|
||
; add ecx,[ystep]
|
||
; adc ah,dh
|
||
; mov bl,[esi+ebp]
|
||
; add edi,byte +0x2
|
||
; add edx,[xstep]
|
||
; adc al,ch
|
||
; mov dl,[ebx]
|
||
; and eax,0x3f3f
|
||
; mov [edi],dl
|
||
; mov bl,[esi+eax]
|
||
; add ecx,[ystep]
|
||
; adc ah,dh
|
||
; mov dl,[ebx]
|
||
; dec cl
|
||
; jne near .hdoubleloop
|
||
;;; check for final pixel
|
||
;.hchecklast:
|
||
;;; to do
|
||
;.hdone:
|
||
; pop ebx
|
||
; pop edi
|
||
; pop esi
|
||
; pop ebp
|
||
; ret
|
||
|