kolibrios/programs/games/c4/trunk/rng.inc

76 lines
1.6 KiB
PHP
Raw Permalink Normal View History

; C4
; Copyright (c) 2002 Thomas Mathys
; killer@vantage.ch
;
; This file is part of C4.
;
; C4 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.
;
; C4 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.
;
; You should have received a copy of the GNU General Public License
; along with C4; if not, write to the Free Software
; Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
%ifndef _RNG_INC
%define _RNG_INC
section .data
; random seed
seed dd 0
section .text
;**********************************************************
; randomize
; initialize random number generator.
; initialization is done using the get system clock syscall
;
; input : nothing
; output : nothing
; destroys : nothing
;**********************************************************
randomize:
push eax
mov eax,MOS_SC_GETSYSCLOCK
int 0x40
mov [seed],eax
pop eax
ret
;**********************************************************
; rand
; return an unsigned 32 bit "random" number
;
; input : nothing
; output : eax = unsigned 32 bit random number
; destroys : nothing
;**********************************************************
rand:
pushfd
push edx
mov eax,32719
mul dword [seed]
add eax,123
xchg al,ah
rol eax,16
xchg al,ah
mov [seed],eax
pop edx
popfd
ret
%endif