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783 lines
19 KiB
C++
783 lines
19 KiB
C++
/*
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** music_midi_midiout.cpp
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** Code to let ZDoom play SMF MIDI music through the MIDI streaming API.
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**
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**---------------------------------------------------------------------------
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** Copyright 1998-2008 Randy Heit
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** All rights reserved.
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**
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** Redistribution and use in source and binary forms, with or without
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** modification, are permitted provided that the following conditions
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** are met:
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**
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** 1. Redistributions of source code must retain the above copyright
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** notice, this list of conditions and the following disclaimer.
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** 2. Redistributions in binary form must reproduce the above copyright
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** notice, this list of conditions and the following disclaimer in the
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** documentation and/or other materials provided with the distribution.
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** 3. The name of the author may not be used to endorse or promote products
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** derived from this software without specific prior written permission.
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**
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** THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
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** IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
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** OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
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** IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
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** INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
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** NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
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** DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
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** THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
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** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
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** THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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**---------------------------------------------------------------------------
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**
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** This file also supports the Apogee Sound System's EMIDI files. That
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** basically means you can play the Duke3D songs without any editing and
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** have them sound right.
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*/
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// HEADER FILES ------------------------------------------------------------
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#include "midisource.h"
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#include "zmusic/zmusic_internal.h"
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// MACROS ------------------------------------------------------------------
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// Used by SendCommand to check for unexpected end-of-track conditions.
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#define CHECK_FINISHED \
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if (track->TrackP >= track->MaxTrackP) \
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{ \
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track->Finished = true; \
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return events; \
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}
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// TYPES -------------------------------------------------------------------
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struct MIDISong2::TrackInfo
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{
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const uint8_t *TrackBegin;
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size_t TrackP;
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size_t MaxTrackP;
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uint32_t Delay;
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uint32_t PlayedTime;
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bool Finished;
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uint8_t RunningStatus;
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bool Designated;
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bool EProgramChange;
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bool EVolume;
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uint16_t Designation;
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size_t LoopBegin;
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uint32_t LoopDelay;
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int LoopCount;
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bool LoopFinished;
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uint32_t ReadVarLen ();
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};
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// EXTERNAL FUNCTION PROTOTYPES --------------------------------------------
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// PUBLIC FUNCTION PROTOTYPES ----------------------------------------------
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// PRIVATE FUNCTION PROTOTYPES ---------------------------------------------
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// EXTERNAL DATA DECLARATIONS ----------------------------------------------
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// PRIVATE DATA DEFINITIONS ------------------------------------------------
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// PUBLIC DATA DEFINITIONS -------------------------------------------------
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// CODE --------------------------------------------------------------------
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//==========================================================================
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//
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// MIDISong2 Constructor
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//
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// Buffers the file and does some validation of the SMF header.
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//
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//==========================================================================
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MIDISong2::MIDISong2 (const uint8_t* data, size_t len)
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: MusHeader(0), Tracks(0)
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{
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unsigned p;
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int i;
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MusHeader.resize(len);
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memcpy(MusHeader.data(), data, len);
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// Do some validation of the MIDI file
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if (MusHeader[4] != 0 || MusHeader[5] != 0 || MusHeader[6] != 0 || MusHeader[7] != 6)
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return;
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if (MusHeader[8] != 0 || MusHeader[9] > 2)
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return;
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Format = MusHeader[9];
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if (Format == 0)
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{
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NumTracks = 1;
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}
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else
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{
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NumTracks = MusHeader[10] * 256 + MusHeader[11];
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}
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// The division is the number of pulses per quarter note (PPQN).
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Division = MusHeader[12] * 256 + MusHeader[13];
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if (Division == 0)
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{ // PPQN is zero? Then the song cannot play because it never pulses.
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return;
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}
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Tracks.resize(NumTracks);
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// Gather information about each track
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for (i = 0, p = 14; i < NumTracks && p < MusHeader.size() + 8; ++i)
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{
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uint32_t chunkLen =
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(MusHeader[p+4]<<24) |
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(MusHeader[p+5]<<16) |
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(MusHeader[p+6]<<8) |
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(MusHeader[p+7]);
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if (chunkLen + p + 8 > MusHeader.size())
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{ // Track too long, so truncate it
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chunkLen = (uint32_t)MusHeader.size() - p - 8;
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}
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if (MusHeader[p+0] == 'M' &&
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MusHeader[p+1] == 'T' &&
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MusHeader[p+2] == 'r' &&
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MusHeader[p+3] == 'k')
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{
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Tracks[i].TrackBegin = &MusHeader[p + 8];
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Tracks[i].TrackP = 0;
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Tracks[i].MaxTrackP = chunkLen;
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}
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p += chunkLen + 8;
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}
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// In case there were fewer actual chunks in the file than the
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// header specified, update NumTracks with the current value of i
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NumTracks = i;
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if (NumTracks == 0)
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{ // No tracks, so nothing to play
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return;
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}
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}
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//==========================================================================
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//
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// MIDISong2 :: CheckCaps
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//
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// Find out if this is an FM synth or not for EMIDI's benefit.
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// (Do any released EMIDIs use track designations?)
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//
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//==========================================================================
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void MIDISong2::CheckCaps(int tech)
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{
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DesignationMask = 0xFF0F;
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if (tech == MIDIDEV_FMSYNTH)
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{
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DesignationMask = 0x00F0;
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}
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else if (tech == MIDIDEV_MIDIPORT)
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{
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DesignationMask = 0x0001;
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}
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}
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//==========================================================================
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//
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// MIDISong2 :: DoInitialSetup
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//
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// Sets the starting channel volumes.
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//
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//==========================================================================
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void MIDISong2 :: DoInitialSetup()
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{
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for (int i = 0; i < 16; ++i)
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{
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// The ASS uses a default volume of 90, but all the other
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// sources I can find say it's 100. Ideally, any song that
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// cares about its volume is going to initialize it to
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// whatever it wants and override this default.
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ChannelVolumes[i] = 100;
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}
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}
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//==========================================================================
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//
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// MIDISong2 :: DoRestart
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//
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// Rewinds every track.
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//
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//==========================================================================
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void MIDISong2 :: DoRestart()
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{
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int i;
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// Set initial state.
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for (i = 0; i < NumTracks; ++i)
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{
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Tracks[i].TrackP = 0;
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Tracks[i].Finished = false;
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Tracks[i].RunningStatus = 0;
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Tracks[i].Designated = false;
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Tracks[i].Designation = 0;
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Tracks[i].LoopCount = -1;
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Tracks[i].EProgramChange = false;
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Tracks[i].EVolume = false;
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Tracks[i].PlayedTime = 0;
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}
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ProcessInitialMetaEvents ();
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for (i = 0; i < NumTracks; ++i)
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{
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Tracks[i].Delay = Tracks[i].ReadVarLen();
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}
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TrackDue = Tracks.data();
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TrackDue = FindNextDue();
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}
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//==========================================================================
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//
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// MIDISong2 :: CheckDone
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//
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//==========================================================================
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bool MIDISong2::CheckDone()
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{
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return TrackDue == nullptr;
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}
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//==========================================================================
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//
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// MIDISong2 :: MakeEvents
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//
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// Copies MIDI events from the SMF and puts them into a MIDI stream
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// buffer. Returns the new position in the buffer.
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//
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//==========================================================================
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uint32_t *MIDISong2::MakeEvents(uint32_t *events, uint32_t *max_event_p, uint32_t max_time)
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{
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uint32_t *start_events;
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uint32_t tot_time = 0;
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uint32_t time = 0;
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uint32_t delay;
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start_events = events;
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while (TrackDue && events < max_event_p && tot_time <= max_time)
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{
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// It's possible that this tick may be nothing but meta-events and
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// not generate any real events. Repeat this until we actually
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// get some output so we don't send an empty buffer to the MIDI
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// device.
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do
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{
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delay = TrackDue->Delay;
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time += delay;
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// Advance time for all tracks by the amount needed for the one up next.
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tot_time += delay * Tempo / Division;
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AdvanceTracks(delay);
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// Play all events for this tick.
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do
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{
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bool sysex_noroom = false;
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uint32_t *new_events = SendCommand(events, TrackDue, time, max_event_p - events, sysex_noroom);
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if (sysex_noroom)
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{
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return events;
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}
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TrackDue = FindNextDue();
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if (new_events != events)
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{
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time = 0;
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}
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events = new_events;
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}
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while (TrackDue && TrackDue->Delay == 0 && events < max_event_p);
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}
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while (start_events == events && TrackDue);
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time = 0;
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}
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return events;
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}
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//==========================================================================
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//
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// MIDISong2 :: AdvanceTracks
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//
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// Advances time for all tracks by the specified amount.
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//
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//==========================================================================
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void MIDISong2::AdvanceTracks(uint32_t time)
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{
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for (int i = 0; i < NumTracks; ++i)
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{
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if (!Tracks[i].Finished)
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{
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Tracks[i].Delay -= time;
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Tracks[i].PlayedTime += time;
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}
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}
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}
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//==========================================================================
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//
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// MIDISong2 :: SendCommand
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//
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// Places a single MIDIEVENT in the event buffer.
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//
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//==========================================================================
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uint32_t *MIDISong2::SendCommand (uint32_t *events, TrackInfo *track, uint32_t delay, ptrdiff_t room, bool &sysex_noroom)
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{
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uint32_t len;
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uint8_t event, data1 = 0, data2 = 0;
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int i;
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sysex_noroom = false;
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size_t start_p = track->TrackP;
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CHECK_FINISHED
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event = track->TrackBegin[track->TrackP++];
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CHECK_FINISHED
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// The actual event type will be filled in below.
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events[0] = delay;
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events[1] = 0;
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events[2] = MEVENT_NOP << 24;
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if (event != MIDI_SYSEX && event != MIDI_META && event != MIDI_SYSEXEND)
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{
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// Normal short message
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if ((event & 0xF0) == 0xF0)
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{
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if (MIDI_CommonLengths[event & 15] > 0)
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{
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data1 = track->TrackBegin[track->TrackP++];
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if (MIDI_CommonLengths[event & 15] > 1)
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{
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data2 = track->TrackBegin[track->TrackP++];
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}
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}
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}
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else if ((event & 0x80) == 0)
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{
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data1 = event;
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event = track->RunningStatus;
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}
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else
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{
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track->RunningStatus = event;
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data1 = track->TrackBegin[track->TrackP++];
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}
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CHECK_FINISHED
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if (MIDI_EventLengths[(event&0x70)>>4] == 2)
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{
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data2 = track->TrackBegin[track->TrackP++];
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}
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switch (event & 0x70)
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{
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case MIDI_PRGMCHANGE & 0x70:
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if (track->EProgramChange)
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{
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event = MIDI_META;
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}
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break;
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case MIDI_CTRLCHANGE & 0x70:
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switch (data1)
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{
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case 7: // Channel volume
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if (track->EVolume)
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{ // Tracks that use EMIDI volume ignore normal volume changes.
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event = MIDI_META;
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}
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else
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{
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data2 = VolumeControllerChange(event & 15, data2);
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}
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break;
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case 7+32: // Channel volume (LSB)
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if (track->EVolume)
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{
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event = MIDI_META;
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}
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// It should be safe to pass this straight through to the
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// MIDI device, since it's a very fine amount.
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break;
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case 110: // EMIDI Track Designation - InitBeat only
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// Instruments 4, 5, 6, and 7 are all FM synth.
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// The rest are all wavetable.
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if (track->PlayedTime < (uint32_t)Division)
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{
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if (data2 == 127)
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{
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track->Designation = ~0;
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track->Designated = true;
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}
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else if (data2 <= 9)
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{
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track->Designation |= 1 << data2;
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track->Designated = true;
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}
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event = MIDI_META;
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}
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break;
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case 111: // EMIDI Track Exclusion - InitBeat only
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if (track->PlayedTime < (uint32_t)Division)
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{
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if (track->Designated && data2 <= 9)
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{
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track->Designation &= ~(1 << data2);
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}
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event = MIDI_META;
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}
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break;
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case 112: // EMIDI Program Change
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// Ignored unless it also appears in the InitBeat
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if (track->PlayedTime < (uint32_t)Division || track->EProgramChange)
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{
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track->EProgramChange = true;
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event = 0xC0 | (event & 0x0F);
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data1 = data2;
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data2 = 0;
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}
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break;
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case 113: // EMIDI Volume
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// Ignored unless it also appears in the InitBeat
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if (track->PlayedTime < (uint32_t)Division || track->EVolume)
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{
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track->EVolume = true;
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data1 = 7;
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data2 = VolumeControllerChange(event & 15, data2);
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}
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break;
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case 116: // EMIDI Loop Begin
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{
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// We convert the loop count to XMIDI conventions before clamping.
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// Then we convert it back to EMIDI conventions after clamping.
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// (XMIDI can create "loops" that don't loop. EMIDI cannot.)
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int loopcount = ClampLoopCount(data2 == 0 ? 0 : data2 + 1);
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if (loopcount != 1)
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{
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track->LoopBegin = track->TrackP;
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track->LoopDelay = 0;
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track->LoopCount = loopcount == 0 ? 0 : loopcount - 1;
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track->LoopFinished = track->Finished;
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}
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}
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event = MIDI_META;
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break;
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case 117: // EMIDI Loop End
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if (track->LoopCount >= 0 && data2 == 127)
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{
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if (track->LoopCount == 0 && !isLooping)
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{
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track->Finished = true;
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}
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else
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{
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if (track->LoopCount > 0 && --track->LoopCount == 0)
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{
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track->LoopCount = -1;
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}
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track->TrackP = track->LoopBegin;
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track->Delay = track->LoopDelay;
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track->Finished = track->LoopFinished;
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}
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}
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event = MIDI_META;
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break;
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case 118: // EMIDI Global Loop Begin
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{
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int loopcount = ClampLoopCount(data2 == 0 ? 0 : data2 + 1);
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if (loopcount != 1)
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{
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for (i = 0; i < NumTracks; ++i)
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{
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Tracks[i].LoopBegin = Tracks[i].TrackP;
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Tracks[i].LoopDelay = Tracks[i].Delay;
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Tracks[i].LoopCount = loopcount == 0 ? 0 : loopcount - 1;
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Tracks[i].LoopFinished = Tracks[i].Finished;
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}
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}
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}
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event = MIDI_META;
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break;
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case 119: // EMIDI Global Loop End
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if (data2 == 127)
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{
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for (i = 0; i < NumTracks; ++i)
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{
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if (Tracks[i].LoopCount >= 0)
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{
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if (Tracks[i].LoopCount == 0 && !isLooping)
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{
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Tracks[i].Finished = true;
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}
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else
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{
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if (Tracks[i].LoopCount > 0 && --Tracks[i].LoopCount == 0)
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{
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Tracks[i].LoopCount = -1;
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}
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Tracks[i].TrackP = Tracks[i].LoopBegin;
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Tracks[i].Delay = Tracks[i].LoopDelay;
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Tracks[i].Finished = Tracks[i].LoopFinished;
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}
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}
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}
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}
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event = MIDI_META;
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break;
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}
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}
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if (event != MIDI_META && (!track->Designated || (track->Designation & DesignationMask)))
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{
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events[2] = event | (data1<<8) | (data2<<16);
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}
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}
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else
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{
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// SysEx events could potentially not have enough room in the buffer...
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if (event == MIDI_SYSEX || event == MIDI_SYSEXEND)
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{
|
|
len = track->ReadVarLen();
|
|
if (len >= (MAX_MIDI_EVENTS-1)*3*4 || skipSysex)
|
|
{ // This message will never fit. Throw it away.
|
|
track->TrackP += len;
|
|
}
|
|
else if (len + 12 >= (size_t)room * 4)
|
|
{ // Not enough room left in this buffer. Backup and wait for the next one.
|
|
track->TrackP = start_p;
|
|
sysex_noroom = true;
|
|
return events;
|
|
}
|
|
else
|
|
{
|
|
uint8_t *msg = (uint8_t *)&events[3];
|
|
if (event == MIDI_SYSEX)
|
|
{ // Need to add the SysEx marker to the message.
|
|
events[2] = (MEVENT_LONGMSG << 24) | (len + 1);
|
|
*msg++ = MIDI_SYSEX;
|
|
}
|
|
else
|
|
{
|
|
events[2] = (MEVENT_LONGMSG << 24) | len;
|
|
}
|
|
memcpy(msg, &track->TrackBegin[track->TrackP], len);
|
|
msg += len;
|
|
// Must pad with 0
|
|
while ((size_t)msg & 3)
|
|
{
|
|
*msg++ = 0;
|
|
}
|
|
track->TrackP += len;
|
|
}
|
|
}
|
|
else if (event == MIDI_META)
|
|
{
|
|
// It's a meta-event
|
|
event = track->TrackBegin[track->TrackP++];
|
|
CHECK_FINISHED
|
|
len = track->ReadVarLen ();
|
|
CHECK_FINISHED
|
|
|
|
if (track->TrackP + len <= track->MaxTrackP)
|
|
{
|
|
switch (event)
|
|
{
|
|
case MIDI_META_EOT:
|
|
track->Finished = true;
|
|
break;
|
|
|
|
case MIDI_META_TEMPO:
|
|
Tempo =
|
|
(track->TrackBegin[track->TrackP+0]<<16) |
|
|
(track->TrackBegin[track->TrackP+1]<<8) |
|
|
(track->TrackBegin[track->TrackP+2]);
|
|
events[0] = delay;
|
|
events[1] = 0;
|
|
events[2] = (MEVENT_TEMPO << 24) | Tempo;
|
|
break;
|
|
}
|
|
track->TrackP += len;
|
|
if (track->TrackP == track->MaxTrackP)
|
|
{
|
|
track->Finished = true;
|
|
}
|
|
}
|
|
else
|
|
{
|
|
track->Finished = true;
|
|
}
|
|
}
|
|
}
|
|
if (!track->Finished)
|
|
{
|
|
track->Delay = track->ReadVarLen();
|
|
}
|
|
// Advance events pointer unless this is a non-delaying NOP.
|
|
if (events[0] != 0 || MEVENT_EVENTTYPE(events[2]) != MEVENT_NOP)
|
|
{
|
|
if (MEVENT_EVENTTYPE(events[2]) == MEVENT_LONGMSG)
|
|
{
|
|
events += 3 + ((MEVENT_EVENTPARM(events[2]) + 3) >> 2);
|
|
}
|
|
else
|
|
{
|
|
events += 3;
|
|
}
|
|
}
|
|
return events;
|
|
}
|
|
|
|
//==========================================================================
|
|
//
|
|
// MIDISong2 :: ProcessInitialMetaEvents
|
|
//
|
|
// Handle all the meta events at the start of each track.
|
|
//
|
|
//==========================================================================
|
|
|
|
void MIDISong2::ProcessInitialMetaEvents ()
|
|
{
|
|
TrackInfo *track;
|
|
int i;
|
|
uint8_t event;
|
|
uint32_t len;
|
|
|
|
for (i = 0; i < NumTracks; ++i)
|
|
{
|
|
track = &Tracks[i];
|
|
while (!track->Finished &&
|
|
track->TrackP < track->MaxTrackP - 4 &&
|
|
track->TrackBegin[track->TrackP] == 0 &&
|
|
track->TrackBegin[track->TrackP+1] == 0xFF)
|
|
{
|
|
event = track->TrackBegin[track->TrackP+2];
|
|
track->TrackP += 3;
|
|
len = track->ReadVarLen ();
|
|
if (track->TrackP + len <= track->MaxTrackP)
|
|
{
|
|
switch (event)
|
|
{
|
|
case MIDI_META_EOT:
|
|
track->Finished = true;
|
|
break;
|
|
|
|
case MIDI_META_TEMPO:
|
|
SetTempo(
|
|
(track->TrackBegin[track->TrackP+0]<<16) |
|
|
(track->TrackBegin[track->TrackP+1]<<8) |
|
|
(track->TrackBegin[track->TrackP+2])
|
|
);
|
|
break;
|
|
}
|
|
}
|
|
track->TrackP += len;
|
|
}
|
|
if (track->TrackP >= track->MaxTrackP - 4)
|
|
{
|
|
track->Finished = true;
|
|
}
|
|
}
|
|
}
|
|
|
|
//==========================================================================
|
|
//
|
|
// MIDISong2 :: TrackInfo :: ReadVarLen
|
|
//
|
|
// Reads a variable-length SMF number.
|
|
//
|
|
//==========================================================================
|
|
|
|
uint32_t MIDISong2::TrackInfo::ReadVarLen ()
|
|
{
|
|
uint32_t time = 0, t = 0x80;
|
|
|
|
while ((t & 0x80) && TrackP < MaxTrackP)
|
|
{
|
|
t = TrackBegin[TrackP++];
|
|
time = (time << 7) | (t & 127);
|
|
}
|
|
return time;
|
|
}
|
|
|
|
//==========================================================================
|
|
//
|
|
// MIDISong2 :: FindNextDue
|
|
//
|
|
// Scans every track for the next event to play. Returns nullptr if all events
|
|
// have been consumed.
|
|
//
|
|
//==========================================================================
|
|
|
|
MIDISong2::TrackInfo *MIDISong2::FindNextDue ()
|
|
{
|
|
TrackInfo *track;
|
|
uint32_t best;
|
|
int i;
|
|
|
|
// Give precedence to whichever track last had events taken from it.
|
|
if (!TrackDue->Finished && TrackDue->Delay == 0)
|
|
{
|
|
return TrackDue;
|
|
}
|
|
|
|
switch (Format)
|
|
{
|
|
case 0:
|
|
return Tracks[0].Finished ? nullptr : Tracks.data();
|
|
|
|
case 1:
|
|
track = nullptr;
|
|
best = 0xFFFFFFFF;
|
|
for (i = 0; i < NumTracks; ++i)
|
|
{
|
|
if (!Tracks[i].Finished)
|
|
{
|
|
if (Tracks[i].Delay < best)
|
|
{
|
|
best = Tracks[i].Delay;
|
|
track = &Tracks[i];
|
|
}
|
|
}
|
|
}
|
|
return track;
|
|
|
|
case 2:
|
|
track = TrackDue;
|
|
if (track->Finished)
|
|
{
|
|
track++;
|
|
}
|
|
return track < &Tracks[NumTracks] ? track : nullptr;
|
|
}
|
|
return nullptr;
|
|
}
|
|
|
|
|