scummvm/engines/mortevielle/asm.cpp

53 lines
1.5 KiB
C++

/* ScummVM - Graphic Adventure Engine
*
* ScummVM is the legal property of its developers, whose names
* are too numerous to list here. Please refer to the COPYRIGHT
* file distributed with this source distribution.
*
* 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.
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*
*/
/*
* This code is based on original Mortville Manor DOS source code
* Copyright (c) 1988-1989 Lankhor
*/
#include "common/scummsys.h"
namespace Mortevielle {
/**
* Decodes a number of 64 byte blocks
* @param pStart Start of data
* @param count Number of 64 byte blocks
*/
void zzuul(byte *pStart, int count) {
while (count-- > 0) {
for (int idx = 0; idx < 64; ++pStart, ++idx) {
uint16 v = ((*pStart - 0x80) << 1) + 0x80;
if (v & 0x8000)
*pStart = 0;
else if (v & 0xff00)
*pStart = 0xff;
else
*pStart = (byte)v;
}
}
}
} // End of namespace Mortevielle