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/*
Copyright (C) 2002-2010 Paul Davis
This program is free software; you can redistribute it and/or modify it
under the terms of the GNU Lesser 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 Lesser General Public
License for more details.
You should have received a copy of the GNU Lesser General Public License
along with this program; if not, write to the Free Software Foundation,
Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
#include <cmath>
#include <cassert>
#include "timecode/bbt_time.h"
using namespace Timecode;
/* This number doesn't describe the smallest division of a "beat" (which is
only defined contextually anyway), but rather the smallest division of the the
divisions of a bar. If using a meter of 4/8, there are 4 divisions per bar, and
we can divide each one into ticks_per_bar_division pieces; in a separate meter
(section) of 3/8, there are 3 divisions per bar, each of which can be divided
into ticks_per_bar_division pieces.
The number is intended to have as many integer factors as possible so that
1/Nth divisions are integer numbers of ticks.
1920 is the largest legal value that be used inside an SMF file, and has many factors.
*/
const double BBT_Time::ticks_per_bar_division = 1920.0;
BBT_Time::BBT_Time (double dbeats)
{
/* NOTE: this does not construct a BBT time in a canonical form,
in that beats may be a very large number, and bars will
always be zero.
*/
assert (dbeats >= 0);
bars = 0;
beats = rint (floor (dbeats));
ticks = rint (floor (BBT_Time::ticks_per_bar_division * fmod (dbeats, 1.0)));
}
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