ref: 6086876239945c2b232b2af305c6dbee2a34b03c
dir: /Game/src/audiolib/midi.c/
/*
Copyright (C) 1994-1995 Apogee Software, Ltd.
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., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*/
/**********************************************************************
module: MIDI.C
author: James R. Dose
date: May 25, 1994
Midi song file playback routines.
(c) Copyright 1994 James R. Dose. All Rights Reserved.
**********************************************************************/
#include <stdlib.h>
#include <time.h>
#include <dos.h>
#include <string.h>
#include "sndcards.h"
#include "interrup.h"
#include "dpmi.h"
#include "standard.h"
#include "task_man.h"
#include "ll_man.h"
#include "usrhooks.h"
#include "music.h"
#include "_midi.h"
#include "midi.h"
#include "debugio.h"
extern int MUSIC_SoundDevice;
static const int _MIDI_CommandLengths[ NUM_MIDI_CHANNELS ] =
{
0, 0, 0, 0, 0, 0, 0, 0, 2, 2, 2, 2, 1, 1, 2, 0
};
static int cdecl ( *_MIDI_RerouteFunctions[ NUM_MIDI_CHANNELS ] )
(
int event,
int c1,
int c2
) = { NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL,
NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL };
static track *_MIDI_TrackPtr = NULL;
static int _MIDI_TrackMemSize;
static int _MIDI_NumTracks;
static int _MIDI_SongActive = FALSE;
static int _MIDI_SongLoaded = FALSE;
static int _MIDI_Loop = FALSE;
static task *_MIDI_PlayRoutine = NULL;
static int _MIDI_Division;
static int _MIDI_Tick = 0;
static int _MIDI_Beat = 1;
static int _MIDI_Measure = 1;
static unsigned _MIDI_Time;
static int _MIDI_BeatsPerMeasure;
static int _MIDI_TicksPerBeat;
static int _MIDI_TimeBase;
static long _MIDI_FPSecondsPerTick;
static unsigned _MIDI_TotalTime;
static int _MIDI_TotalTicks;
static int _MIDI_TotalBeats;
static int _MIDI_TotalMeasures;
static unsigned long _MIDI_PositionInTicks;
static int _MIDI_Context;
static int _MIDI_ActiveTracks;
static int _MIDI_TotalVolume = MIDI_MaxVolume;
static int _MIDI_ChannelVolume[ NUM_MIDI_CHANNELS ];
static int _MIDI_UserChannelVolume[ NUM_MIDI_CHANNELS ] =
{
256, 256, 256, 256, 256, 256, 256, 256,
256, 256, 256, 256, 256, 256, 256, 256
};
static midifuncs *_MIDI_Funcs = NULL;
static int Reset = FALSE;
int MIDI_Tempo = 120;
char MIDI_PatchMap[ 128 ];
/**********************************************************************
Memory locked functions:
**********************************************************************/
#define MIDI_LockStart _MIDI_ReadNumber
/*---------------------------------------------------------------------
Function: _MIDI_ReadNumber
Reads a variable length number from a MIDI track.
---------------------------------------------------------------------*/
static long _MIDI_ReadNumber
(
void *from,
size_t size
)
{
unsigned char *FromPtr;
long value;
if ( size > 4 )
{
size = 4;
}
FromPtr = ( unsigned char * )from;
value = 0;
while( size-- )
{
value <<= 8;
value += *FromPtr++;
}
return( value );
}
/*---------------------------------------------------------------------
Function: _MIDI_ReadDelta
Reads a variable length encoded delta delay time from the MIDI data.
---------------------------------------------------------------------*/
static long _MIDI_ReadDelta
(
track *ptr
)
{
long value;
unsigned char c;
GET_NEXT_EVENT( ptr, value );
if ( value & 0x80 )
{
value &= 0x7f;
do
{
GET_NEXT_EVENT( ptr, c );
value = ( value << 7 ) + ( c & 0x7f );
}
while ( c & 0x80 );
}
return( value );
}
/*---------------------------------------------------------------------
Function: _MIDI_ResetTracks
Sets the track pointers to the beginning of the song.
---------------------------------------------------------------------*/
static void _MIDI_ResetTracks
(
void
)
{
int i;
track *ptr;
_MIDI_Tick = 0;
_MIDI_Beat = 1;
_MIDI_Measure = 1;
_MIDI_Time = 0;
_MIDI_BeatsPerMeasure = 4;
_MIDI_TicksPerBeat = _MIDI_Division;
_MIDI_TimeBase = 4;
_MIDI_PositionInTicks = 0;
_MIDI_ActiveTracks = 0;
_MIDI_Context = 0;
ptr = _MIDI_TrackPtr;
for( i = 0; i < _MIDI_NumTracks; i++ )
{
ptr->pos = ptr->start;
ptr->delay = _MIDI_ReadDelta( ptr );
ptr->active = ptr->EMIDI_IncludeTrack;
ptr->RunningStatus = 0;
ptr->currentcontext = 0;
ptr->context[ 0 ].loopstart = ptr->start;
ptr->context[ 0 ].loopcount = 0;
if ( ptr->active )
{
_MIDI_ActiveTracks++;
}
ptr++;
}
}
/*---------------------------------------------------------------------
Function: _MIDI_AdvanceTick
Increment tick counters.
---------------------------------------------------------------------*/
static void _MIDI_AdvanceTick
(
void
)
{
_MIDI_PositionInTicks++;
_MIDI_Time += _MIDI_FPSecondsPerTick;
_MIDI_Tick++;
while( _MIDI_Tick > _MIDI_TicksPerBeat )
{
_MIDI_Tick -= _MIDI_TicksPerBeat;
_MIDI_Beat++;
}
while( _MIDI_Beat > _MIDI_BeatsPerMeasure )
{
_MIDI_Beat -= _MIDI_BeatsPerMeasure;
_MIDI_Measure++;
}
}
/*---------------------------------------------------------------------
Function: _MIDI_SysEx
Interpret SysEx Event.
---------------------------------------------------------------------*/
static void _MIDI_SysEx
(
track *Track
)
{
int length;
length = _MIDI_ReadDelta( Track );
Track->pos += length;
}
/*---------------------------------------------------------------------
Function: _MIDI_MetaEvent
Interpret Meta Event.
---------------------------------------------------------------------*/
static void _MIDI_MetaEvent
(
track *Track
)
{
int command;
int length;
int denominator;
long tempo;
GET_NEXT_EVENT( Track, command );
GET_NEXT_EVENT( Track, length );
switch( command )
{
case MIDI_END_OF_TRACK :
Track->active = FALSE;
_MIDI_ActiveTracks--;
break;
case MIDI_TEMPO_CHANGE :
tempo = 60000000L / _MIDI_ReadNumber( Track->pos, 3 );
MIDI_SetTempo( tempo );
break;
case MIDI_TIME_SIGNATURE :
if ( ( _MIDI_Tick > 0 ) || ( _MIDI_Beat > 1 ) )
{
_MIDI_Measure++;
}
_MIDI_Tick = 0;
_MIDI_Beat = 1;
_MIDI_BeatsPerMeasure = (int)*Track->pos;
denominator = (int)*( Track->pos + 1 );
_MIDI_TimeBase = 1;
while( denominator > 0 )
{
_MIDI_TimeBase += _MIDI_TimeBase;
denominator--;
}
_MIDI_TicksPerBeat = ( _MIDI_Division * 4 ) / _MIDI_TimeBase;
break;
}
Track->pos += length;
}
/*---------------------------------------------------------------------
Function: _MIDI_InterpretControllerInfo
Interprets the MIDI controller info.
---------------------------------------------------------------------*/
static int _MIDI_InterpretControllerInfo
(
track *Track,
int TimeSet,
int channel,
int c1,
int c2
)
{
track *trackptr;
int tracknum;
int loopcount;
switch( c1 )
{
case MIDI_MONO_MODE_ON :
Track->pos++;
break;
case MIDI_VOLUME :
if ( !Track->EMIDI_VolumeChange )
{
_MIDI_SetChannelVolume( channel, c2 );
}
break;
case EMIDI_INCLUDE_TRACK :
case EMIDI_EXCLUDE_TRACK :
break;
case EMIDI_PROGRAM_CHANGE :
if ( Track->EMIDI_ProgramChange )
{
_MIDI_Funcs->ProgramChange( channel, MIDI_PatchMap[ c2 & 0x7f ] );
}
break;
case EMIDI_VOLUME_CHANGE :
if ( Track->EMIDI_VolumeChange )
{
_MIDI_SetChannelVolume( channel, c2 );
}
break;
case EMIDI_CONTEXT_START :
break;
case EMIDI_CONTEXT_END :
if ( ( Track->currentcontext == _MIDI_Context ) ||
( _MIDI_Context < 0 ) ||
( Track->context[ _MIDI_Context ].pos == NULL ) )
{
break;
}
Track->currentcontext = _MIDI_Context;
Track->context[ 0 ].loopstart = Track->context[ _MIDI_Context ].loopstart;
Track->context[ 0 ].loopcount = Track->context[ _MIDI_Context ].loopcount;
Track->pos = Track->context[ _MIDI_Context ].pos;
Track->RunningStatus = Track->context[ _MIDI_Context ].RunningStatus;
if ( TimeSet )
{
break;
}
_MIDI_Time = Track->context[ _MIDI_Context ].time;
_MIDI_FPSecondsPerTick = Track->context[ _MIDI_Context ].FPSecondsPerTick;
_MIDI_Tick = Track->context[ _MIDI_Context ].tick;
_MIDI_Beat = Track->context[ _MIDI_Context ].beat;
_MIDI_Measure = Track->context[ _MIDI_Context ].measure;
_MIDI_BeatsPerMeasure = Track->context[ _MIDI_Context ].BeatsPerMeasure;
_MIDI_TicksPerBeat = Track->context[ _MIDI_Context ].TicksPerBeat;
_MIDI_TimeBase = Track->context[ _MIDI_Context ].TimeBase;
TimeSet = TRUE;
break;
case EMIDI_LOOP_START :
case EMIDI_SONG_LOOP_START :
if ( c2 == 0 )
{
loopcount = EMIDI_INFINITE;
}
else
{
loopcount = c2;
}
if ( c1 == EMIDI_SONG_LOOP_START )
{
trackptr = _MIDI_TrackPtr;
tracknum = _MIDI_NumTracks;
}
else
{
trackptr = Track;
tracknum = 1;
}
while( tracknum > 0 )
{
trackptr->context[ 0 ].loopcount = loopcount;
trackptr->context[ 0 ].pos = trackptr->pos;
trackptr->context[ 0 ].loopstart = trackptr->pos;
trackptr->context[ 0 ].RunningStatus = trackptr->RunningStatus;
trackptr->context[ 0 ].active = trackptr->active;
trackptr->context[ 0 ].delay = trackptr->delay;
trackptr->context[ 0 ].time = _MIDI_Time;
trackptr->context[ 0 ].FPSecondsPerTick = _MIDI_FPSecondsPerTick;
trackptr->context[ 0 ].tick = _MIDI_Tick;
trackptr->context[ 0 ].beat = _MIDI_Beat;
trackptr->context[ 0 ].measure = _MIDI_Measure;
trackptr->context[ 0 ].BeatsPerMeasure = _MIDI_BeatsPerMeasure;
trackptr->context[ 0 ].TicksPerBeat = _MIDI_TicksPerBeat;
trackptr->context[ 0 ].TimeBase = _MIDI_TimeBase;
trackptr++;
tracknum--;
}
break;
case EMIDI_LOOP_END :
case EMIDI_SONG_LOOP_END :
if ( ( c2 != EMIDI_END_LOOP_VALUE ) ||
( Track->context[ 0 ].loopstart == NULL ) ||
( Track->context[ 0 ].loopcount == 0 ) )
{
break;
}
if ( c1 == EMIDI_SONG_LOOP_END )
{
trackptr = _MIDI_TrackPtr;
tracknum = _MIDI_NumTracks;
_MIDI_ActiveTracks = 0;
}
else
{
trackptr = Track;
tracknum = 1;
_MIDI_ActiveTracks--;
}
while( tracknum > 0 )
{
if ( trackptr->context[ 0 ].loopcount != EMIDI_INFINITE )
{
trackptr->context[ 0 ].loopcount--;
}
trackptr->pos = trackptr->context[ 0 ].loopstart;
trackptr->RunningStatus = trackptr->context[ 0 ].RunningStatus;
trackptr->delay = trackptr->context[ 0 ].delay;
trackptr->active = trackptr->context[ 0 ].active;
if ( trackptr->active )
{
_MIDI_ActiveTracks++;
}
if ( !TimeSet )
{
_MIDI_Time = trackptr->context[ 0 ].time;
_MIDI_FPSecondsPerTick = trackptr->context[ 0 ].FPSecondsPerTick;
_MIDI_Tick = trackptr->context[ 0 ].tick;
_MIDI_Beat = trackptr->context[ 0 ].beat;
_MIDI_Measure = trackptr->context[ 0 ].measure;
_MIDI_BeatsPerMeasure = trackptr->context[ 0 ].BeatsPerMeasure;
_MIDI_TicksPerBeat = trackptr->context[ 0 ].TicksPerBeat;
_MIDI_TimeBase = trackptr->context[ 0 ].TimeBase;
TimeSet = TRUE;
}
trackptr++;
tracknum--;
}
break;
default :
if ( _MIDI_Funcs->ControlChange )
{
_MIDI_Funcs->ControlChange( channel, c1, c2 );
}
}
return TimeSet;
}
/*---------------------------------------------------------------------
Function: _MIDI_ServiceRoutine
Task that interperates the MIDI data.
---------------------------------------------------------------------*/
// NOTE: We have to use a stack frame here because of a strange bug
// that occurs with Watcom. This means that we cannot access Task!
//Turned off to test if it works with Watcom 10a
//#pragma aux _MIDI_ServiceRoutine frame;
/*
static void test
(
task *Task
)
{
_MIDI_ServiceRoutine( Task );
_MIDI_ServiceRoutine( Task );
_MIDI_ServiceRoutine( Task );
_MIDI_ServiceRoutine( Task );
}
*/
static void _MIDI_ServiceRoutine
(
task *Task
)
{
int event;
int channel;
int command;
track *Track;
int tracknum;
int status;
int c1;
int c2;
int TimeSet = FALSE;
if ( !_MIDI_SongActive )
{
return;
}
Track = _MIDI_TrackPtr;
tracknum = 0;
while( tracknum < _MIDI_NumTracks )
{
while ( ( Track->active ) && ( Track->delay == 0 ) )
{
GET_NEXT_EVENT( Track, event );
if ( GET_MIDI_COMMAND( event ) == MIDI_SPECIAL )
{
switch( event )
{
case MIDI_SYSEX :
case MIDI_SYSEX_CONTINUE :
_MIDI_SysEx( Track );
break;
case MIDI_META_EVENT :
_MIDI_MetaEvent( Track );
break;
}
if ( Track->active )
{
Track->delay = _MIDI_ReadDelta( Track );
}
continue;
}
if ( event & MIDI_RUNNING_STATUS )
{
Track->RunningStatus = event;
}
else
{
event = Track->RunningStatus;
Track->pos--;
}
channel = GET_MIDI_CHANNEL( event );
command = GET_MIDI_COMMAND( event );
if ( _MIDI_CommandLengths[ command ] > 0 )
{
GET_NEXT_EVENT( Track, c1 );
if ( _MIDI_CommandLengths[ command ] > 1 )
{
GET_NEXT_EVENT( Track, c2 );
}
}
if ( _MIDI_RerouteFunctions[ channel ] != NULL )
{
status = _MIDI_RerouteFunctions[ channel ]( event, c1, c2 );
if ( status == MIDI_DONT_PLAY )
{
Track->delay = _MIDI_ReadDelta( Track );
continue;
}
}
switch ( command )
{
case MIDI_NOTE_OFF :
if ( _MIDI_Funcs->NoteOff )
{
_MIDI_Funcs->NoteOff( channel, c1, c2 );
}
break;
case MIDI_NOTE_ON :
if ( _MIDI_Funcs->NoteOn )
{
_MIDI_Funcs->NoteOn( channel, c1, c2 );
}
break;
case MIDI_POLY_AFTER_TCH :
if ( _MIDI_Funcs->PolyAftertouch )
{
_MIDI_Funcs->PolyAftertouch( channel, c1, c2 );
}
break;
case MIDI_CONTROL_CHANGE :
TimeSet = _MIDI_InterpretControllerInfo( Track, TimeSet,
channel, c1, c2 );
break;
case MIDI_PROGRAM_CHANGE :
if ( ( _MIDI_Funcs->ProgramChange ) &&
( !Track->EMIDI_ProgramChange ) )
{
_MIDI_Funcs->ProgramChange( channel, MIDI_PatchMap[ c1 & 0x7f ] );
}
break;
case MIDI_AFTER_TOUCH :
if ( _MIDI_Funcs->ChannelAftertouch )
{
_MIDI_Funcs->ChannelAftertouch( channel, c1 );
}
break;
case MIDI_PITCH_BEND :
if ( _MIDI_Funcs->PitchBend )
{
_MIDI_Funcs->PitchBend( channel, c1, c2 );
}
break;
default :
break;
}
Track->delay = _MIDI_ReadDelta( Track );
}
Track->delay--;
Track++;
tracknum++;
if ( _MIDI_ActiveTracks == 0 )
{
_MIDI_ResetTracks();
if ( _MIDI_Loop )
{
tracknum = 0;
Track = _MIDI_TrackPtr;
}
else
{
_MIDI_SongActive = FALSE;
break;
}
}
}
_MIDI_AdvanceTick();
}
/*---------------------------------------------------------------------
Function: _MIDI_SendControlChange
Sends a control change to the proper device
---------------------------------------------------------------------*/
static int _MIDI_SendControlChange
(
int channel,
int c1,
int c2
)
{
int status;
if ( _MIDI_RerouteFunctions[ channel ] != NULL )
{
status = _MIDI_RerouteFunctions[ channel ]( 0xB0 + channel,
c1, c2 );
if ( status == MIDI_DONT_PLAY )
{
return( MIDI_Ok );
}
}
if ( _MIDI_Funcs == NULL )
{
return( MIDI_Error );
}
if ( _MIDI_Funcs->ControlChange == NULL )
{
return( MIDI_Error );
}
_MIDI_Funcs->ControlChange( channel, c1, c2 );
return( MIDI_Ok );
}
/*---------------------------------------------------------------------
Function: MIDI_RerouteMidiChannel
Sets callback function to reroute MIDI commands from specified
function.
---------------------------------------------------------------------*/
void MIDI_RerouteMidiChannel
(
int channel,
int cdecl ( *function )( int event, int c1, int c2 )
)
{
if ( ( channel >= 1 ) && ( channel <= 16 ) )
{
_MIDI_RerouteFunctions[ channel - 1 ] = function;
}
}
/*---------------------------------------------------------------------
Function: MIDI_AllNotesOff
Sends all notes off commands on all midi channels.
---------------------------------------------------------------------*/
int MIDI_AllNotesOff
(
void
)
{
int channel;
for( channel = 0; channel < NUM_MIDI_CHANNELS; channel++ )
{
_MIDI_SendControlChange( channel, 0x40, 0 );
_MIDI_SendControlChange( channel, MIDI_ALL_NOTES_OFF, 0 );
_MIDI_SendControlChange( channel, 0x78, 0 );
}
return( MIDI_Ok );
}
/*---------------------------------------------------------------------
Function: _MIDI_SetChannelVolume
Sets the volume of the specified midi channel.
---------------------------------------------------------------------*/
static void _MIDI_SetChannelVolume
(
int channel,
int volume
)
{
int status;
int remotevolume;
_MIDI_ChannelVolume[ channel ] = volume;
if ( _MIDI_RerouteFunctions[ channel ] != NULL )
{
remotevolume = volume * _MIDI_TotalVolume;
remotevolume *= _MIDI_UserChannelVolume[ channel ];
remotevolume /= MIDI_MaxVolume;
remotevolume >>= 8;
status = _MIDI_RerouteFunctions[ channel ]( 0xB0 + channel,
MIDI_VOLUME, remotevolume );
if ( status == MIDI_DONT_PLAY )
{
return;
}
}
if ( _MIDI_Funcs == NULL )
{
return;
}
if ( _MIDI_Funcs->ControlChange == NULL )
{
return;
}
// For user volume
volume *= _MIDI_UserChannelVolume[ channel ];
if ( _MIDI_Funcs->SetVolume == NULL )
{
volume *= _MIDI_TotalVolume;
volume /= MIDI_MaxVolume;
}
// For user volume
volume >>= 8;
_MIDI_Funcs->ControlChange( channel, MIDI_VOLUME, volume );
}
/*---------------------------------------------------------------------
Function: MIDI_SetUserChannelVolume
Sets the volume of the specified midi channel.
---------------------------------------------------------------------*/
void MIDI_SetUserChannelVolume
(
int channel,
int volume
)
{
// Convert channel from 1-16 to 0-15
channel--;
volume = max( 0, volume );
volume = min( volume, 256 );
if ( ( channel >= 0 ) && ( channel < NUM_MIDI_CHANNELS ) )
{
_MIDI_UserChannelVolume[ channel ] = volume;
_MIDI_SetChannelVolume( channel, _MIDI_ChannelVolume[ channel ] );
}
}
/*---------------------------------------------------------------------
Function: MIDI_ResetUserChannelVolume
Sets the volume of the specified midi channel.
---------------------------------------------------------------------*/
void MIDI_ResetUserChannelVolume
(
void
)
{
int channel;
for( channel = 0; channel < NUM_MIDI_CHANNELS; channel++ )
{
_MIDI_UserChannelVolume[ channel ] = 256;
}
_MIDI_SendChannelVolumes();
}
/*---------------------------------------------------------------------
Function: _MIDI_SendChannelVolumes
Sets the volume on all the midi channels.
---------------------------------------------------------------------*/
static void _MIDI_SendChannelVolumes
(
void
)
{
int channel;
for( channel = 0; channel < NUM_MIDI_CHANNELS; channel++ )
{
_MIDI_SetChannelVolume( channel, _MIDI_ChannelVolume[ channel ] );
}
}
/*---------------------------------------------------------------------
Function: MIDI_Reset
Resets the MIDI device to General Midi defaults.
---------------------------------------------------------------------*/
int MIDI_Reset
(
void
)
{
int channel;
long time;
unsigned flags;
MIDI_AllNotesOff();
flags = DisableInterrupts();
_enable();
time = clock() + CLOCKS_PER_SEC/24;
while(clock() < time)
;
RestoreInterrupts( flags );
for( channel = 0; channel < NUM_MIDI_CHANNELS; channel++ )
{
_MIDI_SendControlChange( channel, MIDI_RESET_ALL_CONTROLLERS, 0 );
_MIDI_SendControlChange( channel, MIDI_RPN_MSB, MIDI_PITCHBEND_MSB );
_MIDI_SendControlChange( channel, MIDI_RPN_LSB, MIDI_PITCHBEND_LSB );
_MIDI_SendControlChange( channel, MIDI_DATAENTRY_MSB, 2 ); /* Pitch Bend Sensitivity MSB */
_MIDI_SendControlChange( channel, MIDI_DATAENTRY_LSB, 0 ); /* Pitch Bend Sensitivity LSB */
_MIDI_ChannelVolume[ channel ] = GENMIDI_DefaultVolume;
}
_MIDI_SendChannelVolumes();
Reset = TRUE;
return( MIDI_Ok );
}
/*---------------------------------------------------------------------
Function: MIDI_SetVolume
Sets the total volume of the music.
---------------------------------------------------------------------*/
int MIDI_SetVolume
(
int volume
)
{
int i;
if ( _MIDI_Funcs == NULL )
{
return( MIDI_NullMidiModule );
}
volume = min( MIDI_MaxVolume, volume );
volume = max( 0, volume );
_MIDI_TotalVolume = volume;
if ( _MIDI_Funcs->SetVolume )
{
_MIDI_Funcs->SetVolume( volume );
for( i = 0; i < NUM_MIDI_CHANNELS; i++ )
{
if ( _MIDI_RerouteFunctions[ i ] != NULL )
{
_MIDI_SetChannelVolume( i, _MIDI_ChannelVolume[ i ] );
}
}
}
else
{
_MIDI_SendChannelVolumes();
}
return( MIDI_Ok );
}
/*---------------------------------------------------------------------
Function: MIDI_GetVolume
Returns the total volume of the music.
---------------------------------------------------------------------*/
int MIDI_GetVolume
(
void
)
{
int volume;
if ( _MIDI_Funcs == NULL )
{
return( MIDI_NullMidiModule );
}
if ( _MIDI_Funcs->GetVolume )
{
volume = _MIDI_Funcs->GetVolume();
}
else
{
volume = _MIDI_TotalVolume;
}
return( volume );
}
/*---------------------------------------------------------------------
Function: MIDI_SetContext
Sets the song context.
---------------------------------------------------------------------*/
void MIDI_SetContext
(
int context
)
{
if ( ( context > 0 ) && ( context < EMIDI_NUM_CONTEXTS ) )
{
_MIDI_Context = context;
}
}
/*---------------------------------------------------------------------
Function: MIDI_GetContext
Returns the current song context.
---------------------------------------------------------------------*/
int MIDI_GetContext
(
void
)
{
return _MIDI_Context;
}
/*---------------------------------------------------------------------
Function: MIDI_SetLoopFlag
Sets whether the song should loop when finished or not.
---------------------------------------------------------------------*/
void MIDI_SetLoopFlag
(
int loopflag
)
{
_MIDI_Loop = loopflag;
}
/*---------------------------------------------------------------------
Function: MIDI_ContinueSong
Continues playback of a paused song.
---------------------------------------------------------------------*/
void MIDI_ContinueSong
(
void
)
{
if ( _MIDI_SongLoaded )
{
_MIDI_SongActive = TRUE;
}
}
/*---------------------------------------------------------------------
Function: MIDI_PauseSong
Pauses playback of the current song.
---------------------------------------------------------------------*/
void MIDI_PauseSong
(
void
)
{
if ( _MIDI_SongLoaded )
{
_MIDI_SongActive = FALSE;
MIDI_AllNotesOff();
}
}
/*---------------------------------------------------------------------
Function: MIDI_SongPlaying
Returns whether a song is playing or not.
---------------------------------------------------------------------*/
int MIDI_SongPlaying
(
void
)
{
return( _MIDI_SongActive );
}
/*---------------------------------------------------------------------
Function: MIDI_SetMidiFuncs
Selects the routines that send the MIDI data to the music device.
---------------------------------------------------------------------*/
void MIDI_SetMidiFuncs
(
midifuncs *funcs
)
{
_MIDI_Funcs = funcs;
}
/*---------------------------------------------------------------------
Function: MIDI_StopSong
Stops playback of the currently playing song.
---------------------------------------------------------------------*/
void MIDI_StopSong
(
void
)
{
if ( _MIDI_SongLoaded )
{
TS_Terminate( _MIDI_PlayRoutine );
_MIDI_PlayRoutine = NULL;
_MIDI_SongActive = FALSE;
_MIDI_SongLoaded = FALSE;
MIDI_Reset();
_MIDI_ResetTracks();
if ( _MIDI_Funcs->ReleasePatches )
{
_MIDI_Funcs->ReleasePatches();
}
DPMI_UnlockMemory( _MIDI_TrackPtr, _MIDI_TrackMemSize );
USRHOOKS_FreeMem( _MIDI_TrackPtr );
_MIDI_TrackPtr = NULL;
_MIDI_NumTracks = 0;
_MIDI_TrackMemSize = 0;
_MIDI_TotalTime = 0;
_MIDI_TotalTicks = 0;
_MIDI_TotalBeats = 0;
_MIDI_TotalMeasures = 0;
}
}
/*---------------------------------------------------------------------
Function: MIDI_PlaySong
Begins playback of a MIDI song.
---------------------------------------------------------------------*/
int MIDI_PlaySong
(
unsigned char *song,
int loopflag
)
{
int numtracks;
int format;
long headersize;
long tracklength;
track *CurrentTrack;
unsigned char *ptr;
int status;
if ( _MIDI_SongLoaded )
{
MIDI_StopSong();
}
_MIDI_Loop = loopflag;
if ( _MIDI_Funcs == NULL )
{
return( MIDI_NullMidiModule );
}
if ( *( unsigned long * )song != MIDI_HEADER_SIGNATURE )
{
return( MIDI_InvalidMidiFile );
}
song += 4;
headersize = _MIDI_ReadNumber( song, 4 );
song += 4;
format = _MIDI_ReadNumber( song, 2 );
_MIDI_NumTracks = _MIDI_ReadNumber( song + 2, 2 );
_MIDI_Division = _MIDI_ReadNumber( song + 4, 2 );
if ( _MIDI_Division < 0 )
{
// If a SMPTE time division is given, just set to 96 so no errors occur
_MIDI_Division = 96;
}
if ( format > MAX_FORMAT )
{
return( MIDI_UnknownMidiFormat );
}
ptr = song + headersize;
if ( _MIDI_NumTracks == 0 )
{
return( MIDI_NoTracks );
}
_MIDI_TrackMemSize = _MIDI_NumTracks * sizeof( track );
status = USRHOOKS_GetMem( &_MIDI_TrackPtr, _MIDI_TrackMemSize );
if ( status != USRHOOKS_Ok )
{
return( MIDI_NoMemory );
}
status = DPMI_LockMemory( _MIDI_TrackPtr, _MIDI_TrackMemSize );
if ( status != DPMI_Ok )
{
USRHOOKS_FreeMem( _MIDI_TrackPtr );
_MIDI_TrackPtr = NULL;
_MIDI_TrackMemSize = 0;
_MIDI_NumTracks = 0;
// MIDI_SetErrorCode( MIDI_DPMI_Error );
return( MIDI_Error );
}
CurrentTrack = _MIDI_TrackPtr;
numtracks = _MIDI_NumTracks;
while( numtracks-- )
{
if ( *( unsigned long * )ptr != MIDI_TRACK_SIGNATURE )
{
DPMI_UnlockMemory( _MIDI_TrackPtr, _MIDI_TrackMemSize );
USRHOOKS_FreeMem( _MIDI_TrackPtr );
_MIDI_TrackPtr = NULL;
_MIDI_TrackMemSize = 0;
return( MIDI_InvalidTrack );
}
tracklength = _MIDI_ReadNumber( ptr + 4, 4 );
ptr += 8;
CurrentTrack->start = ptr;
ptr += tracklength;
CurrentTrack++;
}
if ( _MIDI_Funcs->GetVolume != NULL )
{
_MIDI_TotalVolume = _MIDI_Funcs->GetVolume();
}
_MIDI_InitEMIDI();
if ( _MIDI_Funcs->LoadPatch )
{
MIDI_LoadTimbres();
}
_MIDI_ResetTracks();
if ( !Reset )
{
MIDI_Reset();
}
Reset = FALSE;
_MIDI_PlayRoutine = TS_ScheduleTask( _MIDI_ServiceRoutine, 100, 1, NULL );
// _MIDI_PlayRoutine = TS_ScheduleTask( test, 100, 1, NULL );
MIDI_SetTempo( 120 );
TS_Dispatch();
_MIDI_SongLoaded = TRUE;
_MIDI_SongActive = TRUE;
return( MIDI_Ok );
}
/*---------------------------------------------------------------------
Function: MIDI_SetTempo
Sets the song tempo.
---------------------------------------------------------------------*/
void MIDI_SetTempo
(
int tempo
)
{
long tickspersecond;
MIDI_Tempo = tempo;
tickspersecond = ( tempo * _MIDI_Division ) / 60;
if ( _MIDI_PlayRoutine != NULL )
{
TS_SetTaskRate( _MIDI_PlayRoutine, tickspersecond );
// TS_SetTaskRate( _MIDI_PlayRoutine, tickspersecond / 4 );
}
_MIDI_FPSecondsPerTick = ( 1 << TIME_PRECISION ) / tickspersecond;
}
/*---------------------------------------------------------------------
Function: MIDI_GetTempo
Returns the song tempo.
---------------------------------------------------------------------*/
int MIDI_GetTempo
(
void
)
{
return( MIDI_Tempo );
}
/*---------------------------------------------------------------------
Function: _MIDI_ProcessNextTick
Sets the position of the song pointer.
---------------------------------------------------------------------*/
static int _MIDI_ProcessNextTick
(
void
)
{
int event;
int channel;
int command;
track *Track;
int tracknum;
int status;
int c1;
int c2;
int TimeSet = FALSE;
Track = _MIDI_TrackPtr;
tracknum = 0;
while( ( tracknum < _MIDI_NumTracks ) && ( Track != NULL ) )
{
while ( ( Track->active ) && ( Track->delay == 0 ) )
{
GET_NEXT_EVENT( Track, event );
if ( GET_MIDI_COMMAND( event ) == MIDI_SPECIAL )
{
switch( event )
{
case MIDI_SYSEX :
case MIDI_SYSEX_CONTINUE :
_MIDI_SysEx( Track );
break;
case MIDI_META_EVENT :
_MIDI_MetaEvent( Track );
break;
}
if ( Track->active )
{
Track->delay = _MIDI_ReadDelta( Track );
}
continue;
}
if ( event & MIDI_RUNNING_STATUS )
{
Track->RunningStatus = event;
}
else
{
event = Track->RunningStatus;
Track->pos--;
}
channel = GET_MIDI_CHANNEL( event );
command = GET_MIDI_COMMAND( event );
if ( _MIDI_CommandLengths[ command ] > 0 )
{
GET_NEXT_EVENT( Track, c1 );
if ( _MIDI_CommandLengths[ command ] > 1 )
{
GET_NEXT_EVENT( Track, c2 );
}
}
if ( _MIDI_RerouteFunctions[ channel ] != NULL )
{
status = _MIDI_RerouteFunctions[ channel ]( event, c1, c2 );
if ( status == MIDI_DONT_PLAY )
{
Track->delay = _MIDI_ReadDelta( Track );
continue;
}
}
switch ( command )
{
case MIDI_NOTE_OFF :
break;
case MIDI_NOTE_ON :
break;
case MIDI_POLY_AFTER_TCH :
if ( _MIDI_Funcs->PolyAftertouch )
{
_MIDI_Funcs->PolyAftertouch( channel, c1, c2 );
}
break;
case MIDI_CONTROL_CHANGE :
TimeSet = _MIDI_InterpretControllerInfo( Track, TimeSet,
channel, c1, c2 );
break;
case MIDI_PROGRAM_CHANGE :
if ( ( _MIDI_Funcs->ProgramChange ) &&
( !Track->EMIDI_ProgramChange ) )
{
_MIDI_Funcs->ProgramChange( channel, c1 );
}
break;
case MIDI_AFTER_TOUCH :
if ( _MIDI_Funcs->ChannelAftertouch )
{
_MIDI_Funcs->ChannelAftertouch( channel, c1 );
}
break;
case MIDI_PITCH_BEND :
if ( _MIDI_Funcs->PitchBend )
{
_MIDI_Funcs->PitchBend( channel, c1, c2 );
}
break;
default :
break;
}
Track->delay = _MIDI_ReadDelta( Track );
}
Track->delay--;
Track++;
tracknum++;
if ( _MIDI_ActiveTracks == 0 )
{
break;
}
}
_MIDI_AdvanceTick();
return( TimeSet );
}
/*---------------------------------------------------------------------
Function: MIDI_SetSongTick
Sets the position of the song pointer.
---------------------------------------------------------------------*/
void MIDI_SetSongTick
(
unsigned long PositionInTicks
)
{
if ( !_MIDI_SongLoaded )
{
return;
}
MIDI_PauseSong();
if ( PositionInTicks < _MIDI_PositionInTicks )
{
_MIDI_ResetTracks();
MIDI_Reset();
}
while( _MIDI_PositionInTicks < PositionInTicks )
{
if ( _MIDI_ProcessNextTick() )
{
break;
}
if ( _MIDI_ActiveTracks == 0 )
{
_MIDI_ResetTracks();
if ( !_MIDI_Loop )
{
return;
}
break;
}
}
MIDI_SetVolume( _MIDI_TotalVolume );
MIDI_ContinueSong();
}
/*---------------------------------------------------------------------
Function: MIDI_SetSongTime
Sets the position of the song pointer.
---------------------------------------------------------------------*/
void MIDI_SetSongTime
(
unsigned long milliseconds
)
{
unsigned long mil;
unsigned long sec;
unsigned long newtime;
if ( !_MIDI_SongLoaded )
{
return;
}
MIDI_PauseSong();
mil = ( ( milliseconds % 1000 ) << TIME_PRECISION ) / 1000;
sec = ( milliseconds / 1000 ) << TIME_PRECISION;
newtime = sec + mil;
if ( newtime < _MIDI_Time )
{
_MIDI_ResetTracks();
MIDI_Reset();
}
while( _MIDI_Time < newtime )
{
if ( _MIDI_ProcessNextTick() )
{
break;
}
if ( _MIDI_ActiveTracks == 0 )
{
_MIDI_ResetTracks();
if ( !_MIDI_Loop )
{
return;
}
break;
}
}
MIDI_SetVolume( _MIDI_TotalVolume );
MIDI_ContinueSong();
}
/*---------------------------------------------------------------------
Function: MIDI_SetSongPosition
Sets the position of the song pointer.
---------------------------------------------------------------------*/
void MIDI_SetSongPosition
(
int measure,
int beat,
int tick
)
{
unsigned long pos;
if ( !_MIDI_SongLoaded )
{
return;
}
MIDI_PauseSong();
pos = RELATIVE_BEAT( measure, beat, tick );
if ( pos < RELATIVE_BEAT( _MIDI_Measure, _MIDI_Beat, _MIDI_Tick ) )
{
_MIDI_ResetTracks();
MIDI_Reset();
}
while( RELATIVE_BEAT( _MIDI_Measure, _MIDI_Beat, _MIDI_Tick ) < pos )
{
if ( _MIDI_ProcessNextTick() )
{
break;
}
if ( _MIDI_ActiveTracks == 0 )
{
_MIDI_ResetTracks();
if ( !_MIDI_Loop )
{
return;
}
break;
}
}
MIDI_SetVolume( _MIDI_TotalVolume );
MIDI_ContinueSong();
}
/*---------------------------------------------------------------------
Function: MIDI_GetSongPosition
Returns the position of the song pointer in Measures, beats, ticks.
---------------------------------------------------------------------*/
void MIDI_GetSongPosition
(
songposition *pos
)
{
unsigned long mil;
unsigned long sec;
mil = ( _MIDI_Time & ( ( 1 << TIME_PRECISION ) - 1 ) ) * 1000;
sec = _MIDI_Time >> TIME_PRECISION;
pos->milliseconds = ( mil >> TIME_PRECISION ) + ( sec * 1000 );
pos->tickposition = _MIDI_PositionInTicks;
pos->measure = _MIDI_Measure;
pos->beat = _MIDI_Beat;
pos->tick = _MIDI_Tick;
}
/*---------------------------------------------------------------------
Function: MIDI_GetSongLength
Returns the length of the song.
---------------------------------------------------------------------*/
void MIDI_GetSongLength
(
songposition *pos
)
{
unsigned long mil;
unsigned long sec;
mil = ( _MIDI_TotalTime & ( ( 1 << TIME_PRECISION ) - 1 ) ) * 1000;
sec = _MIDI_TotalTime >> TIME_PRECISION;
pos->milliseconds = ( mil >> TIME_PRECISION ) + ( sec * 1000 );
pos->measure = _MIDI_TotalMeasures;
pos->beat = _MIDI_TotalBeats;
pos->tick = _MIDI_TotalTicks;
pos->tickposition = 0;
}
/*---------------------------------------------------------------------
Function: MIDI_InitEMIDI
Sets up the EMIDI
---------------------------------------------------------------------*/
static void _MIDI_InitEMIDI
(
void
)
{
int event;
int command;
int channel;
int length;
int IncludeFound;
track *Track;
int tracknum;
int type;
int c1;
int c2;
type = EMIDI_GeneralMIDI;
switch( MUSIC_SoundDevice )
{
case SoundBlaster :
type = EMIDI_SoundBlaster;
break;
case ProAudioSpectrum :
type = EMIDI_ProAudio;
break;
case SoundMan16 :
type = EMIDI_SoundMan16;
break;
case Adlib :
type = EMIDI_Adlib;
break;
case GenMidi :
type = EMIDI_GeneralMIDI;
break;
case SoundCanvas :
type = EMIDI_SoundCanvas;
break;
case Awe32 :
type = EMIDI_AWE32;
break;
case WaveBlaster :
type = EMIDI_WaveBlaster;
break;
case SoundScape :
type = EMIDI_Soundscape;
break;
case UltraSound :
type = EMIDI_Ultrasound;
break;
}
_MIDI_ResetTracks();
_MIDI_TotalTime = 0;
_MIDI_TotalTicks = 0;
_MIDI_TotalBeats = 0;
_MIDI_TotalMeasures = 0;
Track = _MIDI_TrackPtr;
tracknum = 0;
while( ( tracknum < _MIDI_NumTracks ) && ( Track != NULL ) )
{
_MIDI_Tick = 0;
_MIDI_Beat = 1;
_MIDI_Measure = 1;
_MIDI_Time = 0;
_MIDI_BeatsPerMeasure = 4;
_MIDI_TicksPerBeat = _MIDI_Division;
_MIDI_TimeBase = 4;
_MIDI_PositionInTicks = 0;
_MIDI_ActiveTracks = 0;
_MIDI_Context = -1;
Track->RunningStatus = 0;
Track->active = TRUE;
Track->EMIDI_ProgramChange = FALSE;
Track->EMIDI_VolumeChange = FALSE;
Track->EMIDI_IncludeTrack = TRUE;
memset( Track->context, 0, sizeof( Track->context ) );
while( Track->delay > 0 )
{
_MIDI_AdvanceTick();
Track->delay--;
}
IncludeFound = FALSE;
while ( Track->active )
{
GET_NEXT_EVENT( Track, event );
if ( GET_MIDI_COMMAND( event ) == MIDI_SPECIAL )
{
switch( event )
{
case MIDI_SYSEX :
case MIDI_SYSEX_CONTINUE :
_MIDI_SysEx( Track );
break;
case MIDI_META_EVENT :
_MIDI_MetaEvent( Track );
break;
}
if ( Track->active )
{
Track->delay = _MIDI_ReadDelta( Track );
while( Track->delay > 0 )
{
_MIDI_AdvanceTick();
Track->delay--;
}
}
continue;
}
if ( event & MIDI_RUNNING_STATUS )
{
Track->RunningStatus = event;
}
else
{
event = Track->RunningStatus;
Track->pos--;
}
channel = GET_MIDI_CHANNEL( event );
command = GET_MIDI_COMMAND( event );
length = _MIDI_CommandLengths[ command ];
if ( command == MIDI_CONTROL_CHANGE )
{
if ( *Track->pos == MIDI_MONO_MODE_ON )
{
length++;
}
GET_NEXT_EVENT( Track, c1 );
GET_NEXT_EVENT( Track, c2 );
length -= 2;
switch( c1 )
{
case EMIDI_LOOP_START :
case EMIDI_SONG_LOOP_START :
if ( c2 == 0 )
{
Track->context[ 0 ].loopcount = EMIDI_INFINITE;
}
else
{
Track->context[ 0 ].loopcount = c2;
}
Track->context[ 0 ].pos = Track->pos;
Track->context[ 0 ].loopstart = Track->pos;
Track->context[ 0 ].RunningStatus = Track->RunningStatus;
Track->context[ 0 ].time = _MIDI_Time;
Track->context[ 0 ].FPSecondsPerTick = _MIDI_FPSecondsPerTick;
Track->context[ 0 ].tick = _MIDI_Tick;
Track->context[ 0 ].beat = _MIDI_Beat;
Track->context[ 0 ].measure = _MIDI_Measure;
Track->context[ 0 ].BeatsPerMeasure = _MIDI_BeatsPerMeasure;
Track->context[ 0 ].TicksPerBeat = _MIDI_TicksPerBeat;
Track->context[ 0 ].TimeBase = _MIDI_TimeBase;
break;
case EMIDI_LOOP_END :
case EMIDI_SONG_LOOP_END :
if ( c2 == EMIDI_END_LOOP_VALUE )
{
Track->context[ 0 ].loopstart = NULL;
Track->context[ 0 ].loopcount = 0;
}
break;
case EMIDI_INCLUDE_TRACK :
if ( EMIDI_AffectsCurrentCard( c2, type ) )
{
//printf( "Include track %d on card %d\n", tracknum, c2 );
IncludeFound = TRUE;
Track->EMIDI_IncludeTrack = TRUE;
}
else if ( !IncludeFound )
{
//printf( "Track excluded %d on card %d\n", tracknum, c2 );
IncludeFound = TRUE;
Track->EMIDI_IncludeTrack = FALSE;
}
break;
case EMIDI_EXCLUDE_TRACK :
if ( EMIDI_AffectsCurrentCard( c2, type ) )
{
//printf( "Exclude track %d on card %d\n", tracknum, c2 );
Track->EMIDI_IncludeTrack = FALSE;
}
break;
case EMIDI_PROGRAM_CHANGE :
if ( !Track->EMIDI_ProgramChange )
//printf( "Program change on track %d\n", tracknum );
Track->EMIDI_ProgramChange = TRUE;
break;
case EMIDI_VOLUME_CHANGE :
if ( !Track->EMIDI_VolumeChange )
//printf( "Volume change on track %d\n", tracknum );
Track->EMIDI_VolumeChange = TRUE;
break;
case EMIDI_CONTEXT_START :
if ( ( c2 > 0 ) && ( c2 < EMIDI_NUM_CONTEXTS ) )
{
Track->context[ c2 ].pos = Track->pos;
Track->context[ c2 ].loopstart = Track->context[ 0 ].loopstart;
Track->context[ c2 ].loopcount = Track->context[ 0 ].loopcount;
Track->context[ c2 ].RunningStatus = Track->RunningStatus;
Track->context[ c2 ].time = _MIDI_Time;
Track->context[ c2 ].FPSecondsPerTick = _MIDI_FPSecondsPerTick;
Track->context[ c2 ].tick = _MIDI_Tick;
Track->context[ c2 ].beat = _MIDI_Beat;
Track->context[ c2 ].measure = _MIDI_Measure;
Track->context[ c2 ].BeatsPerMeasure = _MIDI_BeatsPerMeasure;
Track->context[ c2 ].TicksPerBeat = _MIDI_TicksPerBeat;
Track->context[ c2 ].TimeBase = _MIDI_TimeBase;
}
break;
case EMIDI_CONTEXT_END :
break;
}
}
Track->pos += length;
Track->delay = _MIDI_ReadDelta( Track );
while( Track->delay > 0 )
{
_MIDI_AdvanceTick();
Track->delay--;
}
}
_MIDI_TotalTime = max( _MIDI_TotalTime, _MIDI_Time );
if ( RELATIVE_BEAT( _MIDI_Measure, _MIDI_Beat, _MIDI_Tick ) >
RELATIVE_BEAT( _MIDI_TotalMeasures, _MIDI_TotalBeats,
_MIDI_TotalTicks ) )
{
_MIDI_TotalTicks = _MIDI_Tick;
_MIDI_TotalBeats = _MIDI_Beat;
_MIDI_TotalMeasures = _MIDI_Measure;
}
Track++;
tracknum++;
}
_MIDI_ResetTracks();
}
/*---------------------------------------------------------------------
Function: MIDI_LoadTimbres
Preloads the timbres on cards that use patch-caching.
---------------------------------------------------------------------*/
void MIDI_LoadTimbres
(
void
)
{
int event;
int command;
int channel;
int length;
int Finished;
track *Track;
int tracknum;
Track = _MIDI_TrackPtr;
tracknum = 0;
while( ( tracknum < _MIDI_NumTracks ) && ( Track != NULL ) )
{
Finished = FALSE;
while ( !Finished )
{
GET_NEXT_EVENT( Track, event );
if ( GET_MIDI_COMMAND( event ) == MIDI_SPECIAL )
{
switch( event )
{
case MIDI_SYSEX :
case MIDI_SYSEX_CONTINUE :
length = _MIDI_ReadDelta( Track );
Track->pos += length;
break;
case MIDI_META_EVENT :
GET_NEXT_EVENT( Track, command );
GET_NEXT_EVENT( Track, length );
if ( command == MIDI_END_OF_TRACK )
{
Finished = TRUE;
}
Track->pos += length;
break;
}
if ( !Finished )
{
_MIDI_ReadDelta( Track );
}
continue;
}
if ( event & MIDI_RUNNING_STATUS )
{
Track->RunningStatus = event;
}
else
{
event = Track->RunningStatus;
Track->pos--;
}
channel = GET_MIDI_CHANNEL( event );
command = GET_MIDI_COMMAND( event );
length = _MIDI_CommandLengths[ command ];
if ( command == MIDI_CONTROL_CHANGE )
{
if ( *Track->pos == MIDI_MONO_MODE_ON )
{
length++;
}
if ( *Track->pos == EMIDI_PROGRAM_CHANGE )
{
_MIDI_Funcs->LoadPatch( *( Track->pos + 1 ) );
}
}
if ( channel == MIDI_RHYTHM_CHANNEL )
{
if ( command == MIDI_NOTE_ON )
{
_MIDI_Funcs->LoadPatch( 128 + *Track->pos );
}
}
else
{
if ( command == MIDI_PROGRAM_CHANGE )
{
_MIDI_Funcs->LoadPatch( *Track->pos );
}
}
Track->pos += length;
_MIDI_ReadDelta( Track );
}
Track++;
tracknum++;
}
_MIDI_ResetTracks();
}
/*---------------------------------------------------------------------
Function: MIDI_LockEnd
Used for determining the length of the functions to lock in memory.
---------------------------------------------------------------------*/
static void MIDI_LockEnd
(
void
)
{
}
/*---------------------------------------------------------------------
Function: MIDI_UnlockMemory
Unlocks all neccessary data.
---------------------------------------------------------------------*/
void MIDI_UnlockMemory
(
void
)
{
DPMI_UnlockMemoryRegion( MIDI_LockStart, MIDI_LockEnd );
DPMI_UnlockMemory( ( void * )&_MIDI_CommandLengths[ 0 ],
sizeof( _MIDI_CommandLengths ) );
DPMI_Unlock( _MIDI_TrackPtr );
DPMI_Unlock( _MIDI_NumTracks );
DPMI_Unlock( _MIDI_SongActive );
DPMI_Unlock( _MIDI_SongLoaded );
DPMI_Unlock( _MIDI_Loop );
DPMI_Unlock( _MIDI_PlayRoutine );
DPMI_Unlock( _MIDI_Division );
DPMI_Unlock( _MIDI_ActiveTracks );
DPMI_Unlock( _MIDI_TotalVolume );
DPMI_Unlock( _MIDI_ChannelVolume );
DPMI_Unlock( _MIDI_Funcs );
DPMI_Unlock( _MIDI_PositionInTicks );
DPMI_Unlock( _MIDI_Division );
DPMI_Unlock( _MIDI_Tick );
DPMI_Unlock( _MIDI_Beat );
DPMI_Unlock( _MIDI_Measure );
DPMI_Unlock( _MIDI_Time );
DPMI_Unlock( _MIDI_BeatsPerMeasure );
DPMI_Unlock( _MIDI_TicksPerBeat );
DPMI_Unlock( _MIDI_TimeBase );
DPMI_Unlock( _MIDI_FPSecondsPerTick );
DPMI_Unlock( _MIDI_Context );
DPMI_Unlock( _MIDI_TotalTime );
DPMI_Unlock( _MIDI_TotalTicks );
DPMI_Unlock( _MIDI_TotalBeats );
DPMI_Unlock( _MIDI_TotalMeasures );
DPMI_Unlock( MIDI_Tempo );
}
/*---------------------------------------------------------------------
Function: MIDI_LockMemory
Locks all neccessary data.
---------------------------------------------------------------------*/
int MIDI_LockMemory
(
void
)
{
int status;
status = DPMI_LockMemoryRegion( MIDI_LockStart, MIDI_LockEnd );
status |= DPMI_LockMemory( ( void * )&_MIDI_CommandLengths[ 0 ],
sizeof( _MIDI_CommandLengths ) );
status |= DPMI_Lock( _MIDI_TrackPtr );
status |= DPMI_Lock( _MIDI_NumTracks );
status |= DPMI_Lock( _MIDI_SongActive );
status |= DPMI_Lock( _MIDI_SongLoaded );
status |= DPMI_Lock( _MIDI_Loop );
status |= DPMI_Lock( _MIDI_PlayRoutine );
status |= DPMI_Lock( _MIDI_Division );
status |= DPMI_Lock( _MIDI_ActiveTracks );
status |= DPMI_Lock( _MIDI_TotalVolume );
status |= DPMI_Lock( _MIDI_ChannelVolume );
status |= DPMI_Lock( _MIDI_Funcs );
status |= DPMI_Lock( _MIDI_PositionInTicks );
status |= DPMI_Lock( _MIDI_Division );
status |= DPMI_Lock( _MIDI_Tick );
status |= DPMI_Lock( _MIDI_Beat );
status |= DPMI_Lock( _MIDI_Measure );
status |= DPMI_Lock( _MIDI_Time );
status |= DPMI_Lock( _MIDI_BeatsPerMeasure );
status |= DPMI_Lock( _MIDI_TicksPerBeat );
status |= DPMI_Lock( _MIDI_TimeBase );
status |= DPMI_Lock( _MIDI_FPSecondsPerTick );
status |= DPMI_Lock( _MIDI_Context );
status |= DPMI_Lock( _MIDI_TotalTime );
status |= DPMI_Lock( _MIDI_TotalTicks );
status |= DPMI_Lock( _MIDI_TotalBeats );
status |= DPMI_Lock( _MIDI_TotalMeasures );
status |= DPMI_Lock( MIDI_Tempo );
if ( status != DPMI_Ok )
{
MIDI_UnlockMemory();
// MIDI_SetErrorCode( MIDI_DPMI_Error );
return( MIDI_Error );
}
return( MIDI_Ok );
}