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/* 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"
#include "mortevielle/sound.h"
namespace Mortevielle {
const int tab[16] = { -96, -72, -48, -32, -20, -12, -8, -4, 0, 4, 8, 12, 20, 32, 48, 72 };
/**
* Decode music data
*/
void demus(const byte *PSrc, byte *PDest, int NbreSeg) {
int seed = 128;
int v;
for (int idx1 = 0; idx1 < (NbreSeg * 2); ++idx1) {
for (int idx2 = 0; idx2 < 64; ++idx2) {
byte srcByte = *PSrc++;
v = tab[srcByte >> 4];
seed += v;
*PDest++ = seed & 0xff;
v = tab[srcByte & 0xf];
seed += v;
*PDest++ = seed & 0xff;
}
}
}
} // End of namespace Mortevielle
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