scummvm/sound/midiparser.h

181 lines
4.4 KiB
C
Raw Normal View History

/* ScummVM - Scumm Interpreter
* Copyright (C) 2001-2003 The ScummVM project
*
* 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.
*
* $Header$
*
*/
#ifndef INCLUDED_MIDIPARSER
#define INCLUDED_MIDIPARSER
class MidiParser;
#include "common/scummsys.h"
class MidiDriver;
//////////////////////////////////////////////////
//
// Support entities
//
//////////////////////////////////////////////////
struct Tracker {
byte * _play_pos;
uint32 _play_time;
uint32 _play_tick;
uint32 _last_event_time;
uint32 _last_event_tick;
byte _running_status;
Tracker() { clear(); }
Tracker (const Tracker &copy) :
_play_pos (copy._play_pos),
_play_time (copy._play_time),
_play_tick (copy._play_tick),
_last_event_time (copy._last_event_time),
_last_event_tick (copy._last_event_tick),
_running_status (copy._running_status)
{ }
void clear() {
_play_pos = 0;
_play_time = 0;
_play_tick = 0;
_last_event_time = 0;
_last_event_tick = 0;
_running_status = 0;
}
};
struct EventInfo {
byte * start; // Points to delta
uint32 delta;
byte event;
union {
struct {
byte param1;
byte param2;
} basic;
struct {
byte type; // Used for METAs
byte * data; // Used for SysEx and METAs
} ext;
};
uint32 length; // Used for SysEx and METAs, and note lengths
byte channel() { return event & 0x0F; }
byte command() { return event >> 4; }
};
struct NoteTimer {
byte channel;
byte note;
uint32 time_left;
NoteTimer() : channel(0), note(0), time_left(0) {}
};
//////////////////////////////////////////////////
//
// MidiParser declaration
//
//////////////////////////////////////////////////
class MidiParser {
private:
uint16 _active_notes[128]; // Each uint16 is a bit mask for channels that have that note on
NoteTimer _hanging_notes[32]; // Supports "smart" jump with notes still playing
byte _hanging_notes_count;
protected:
MidiDriver *_driver;
uint32 _timer_rate;
uint32 _ppqn; // Pulses (ticks) Per Quarter Note
uint32 _tempo; // Microseconds per quarter note
uint32 _psec_per_tick; // Microseconds per tick (_tempo / _ppqn)
bool _autoLoop; // For lightweight clients that don't monitor events
bool _smartJump; // Support smart expiration of hanging notes when jumping
byte * _tracks[32];
byte _num_tracks;
byte _active_track;
Tracker _position;
EventInfo _next_event;
bool _abort_parse; // If a jump or some other interruption occurs
protected:
static uint32 readVLQ (byte * &data);
virtual void resetTracking();
virtual void allNotesOff();
virtual void parseNextEvent (EventInfo &info) = 0;
void activeNote (byte channel, byte note, bool active);
void hangingNote (byte channel, byte note, uint32 ticks_left);
void hangAllActiveNotes();
// Multi-byte read helpers
uint32 read4high (byte * &data) {
uint32 val = 0;
int i;
for (i = 0; i < 4; ++i) val = (val << 8) | *data++;
return val;
}
uint16 read2low (byte * &data) {
uint16 val = 0;
int i;
for (i = 0; i < 2; ++i) val |= (*data++) << (i * 8);
return val;
}
public:
enum {
mpMalformedPitchBends = 1,
mpAutoLoop = 2,
mpSmartJump = 3
};
public:
MidiParser();
virtual ~MidiParser() { allNotesOff(); }
virtual bool loadMusic (byte *data, uint32 size) = 0;
virtual void unloadMusic() = 0;
virtual void property (int prop, int value);
void setMidiDriver (MidiDriver *driver) { _driver = driver; }
void setTimerRate (uint32 rate) { _timer_rate = rate; }
void setTempo (uint32 tempo);
void onTimer();
2003-05-21 06:14:14 +00:00
bool setTrack (int track);
bool jumpToTick (uint32 tick, bool fireEvents = false);
uint32 getTick() { return _position._play_tick; }
static MidiParser *createParser_SMF();
static MidiParser *createParser_XMIDI();
static void timerCallback (void *data) { ((MidiParser *) data)->onTimer(); }
};
#endif