| 123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126 |
- ;
- ; Copyright 2020 Electronic Arts Inc.
- ;
- ; TiberianDawn.DLL and RedAlert.dll and corresponding source code 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 3 of the License, or (at your option) any later version.
- ; TiberianDawn.DLL and RedAlert.dll and corresponding source code is distributed
- ; in the hope that it will be useful, but with permitted additional restrictions
- ; under Section 7 of the GPL. See the GNU General Public License in LICENSE.TXT
- ; distributed with this program. You should have received a copy of the
- ; GNU General Public License along with permitted additional restrictions
- ; with this program. If not, see [https://github.com/electronicarts/CnC_Remastered_Collection]>.
- ;***************************************************************************
- ;** C O N F I D E N T I A L --- W E S T W O O D S T U D I O S I N C **
- ;***************************************************************************
- ;* *
- ;* Project Name : Command & Conquer *
- ;* *
- ;* File Name : COORDA.ASM *
- ;* *
- ;* Programmer : Barry W. Green *
- ;* *
- ;* Start Date : February 17, 1995 *
- ;* *
- ;* Last Update : February 17, 1995 [BWG] *
- ;* *
- ;*-------------------------------------------------------------------------*
- ;* Functions: *
- ;* Cardinal_To_Fixed -- Converts cardinal numbers into a fixed point number. *
- ;* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - *
- IDEAL
- P386
- MODEL USE32 FLAT
- global C Cardinal_To_Fixed :NEAR
- global C Fixed_To_Cardinal :NEAR
- CODESEG
- ;***********************************************************************************************
- ;* Cardinal_To_Fixed -- Converts cardinal numbers into a fixed point number. *
- ;* *
- ;* This utility function will convert cardinal numbers into a fixed point fraction. The *
- ;* use of fixed point numbers occurs throughout the product -- since it is a convenient *
- ;* tool. The fixed point number is based on the formula: *
- ;* *
- ;* result = cardinal / base *
- ;* *
- ;* The accuracy of the fixed point number is limited to 1/65536 as the lowest and up to *
- ;* 65536 as the largest. *
- ;* *
- ;* INPUT: base -- The key number to base the fraction about. *
- ;* *
- ;* cardinal -- The other number (hey -- what do you call it?) *
- ;* *
- ;* OUTPUT: Returns with the fixed point number of the "cardinal" parameter as it relates *
- ;* to the "base" parameter. *
- ;* *
- ;* WARNINGS: none *
- ;* *
- ;* HISTORY: *
- ;* 02/17/1995 BWG : Created. *
- ;*=============================================================================================*/
- ;unsigned int Cardinal_To_Fixed(unsigned base, unsigned cardinal);
- PROC Cardinal_To_Fixed C near
- USES ebx, edx
- ARG base:DWORD
- ARG cardinal:DWORD
- mov eax,0FFFFFFFFh ; establish default return value
- mov ebx,[base]
- or ebx,ebx
- jz near ??retneg1 ; if base==0, return 4294967295
- mov eax,[cardinal] ; otherwise, return (cardinal*65536)/base
- shl eax,16
- xor edx,edx
- div ebx
- ??retneg1:
- ret
- ENDP Cardinal_To_Fixed
- ;***********************************************************************************************
- ;* Fixed_To_Cardinal -- Converts a fixed point number into a cardinal number. *
- ;* *
- ;* Use this routine to convert a fixed point number into a cardinal number. *
- ;* *
- ;* INPUT: base -- The base number that the original fixed point number was created from. *
- ;* *
- ;* fixed -- The fixed point number to convert. *
- ;* *
- ;* OUTPUT: Returns with the reconverted number. *
- ;* *
- ;* WARNINGS: none *
- ;* *
- ;* HISTORY: *
- ;* 02/17/1995 BWG : Created. *
- ;*=============================================================================================*/
- ;unsigned int Fixed_To_Cardinal(unsigned base, unsigned fixed);
- PROC Fixed_To_Cardinal C near
- USES edx
- ARG base:DWORD
- ARG fixed:DWORD
- mov eax,[base]
- mul [fixed]
- add eax,08000h ; eax = (base * fixed) + 0x8000
- shr eax,16 ; return eax/65536
- ret
- ENDP Fixed_To_Cardinal
- END
|
