1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
|
/* ScummVM - Scumm Interpreter
* Copyright (C) 2001/2002 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.
*
* $Header$
*
*/
#include "stdafx.h"
#include "mididrv.h"
#include "engine.h"
#include "common/util.h"
class MidiStreamer : public MidiDriver {
private:
MidiDriver *_target;
StreamCallback *_stream_proc;
void *_stream_param;
volatile int _mode;
volatile bool _paused;
MidiEvent _events [64];
int _event_count;
int _event_index;
long _tempo;
uint16 _ticks_per_beat;
long _delay;
volatile bool _active;
uint32 property(int prop, uint32 param);
static int timer_thread (void *param);
void on_timer (void);
public:
MidiStreamer (MidiDriver *target);
int open(int mode);
void close();
void send(uint32 b) { if (_mode) _target->send (b); }
void pause(bool p) { _paused = p; }
void set_stream_callback(void *param, StreamCallback *sc);
void setPitchBendRange (byte channel, uint range) { _target->setPitchBendRange (channel, range); }
};
MidiStreamer::MidiStreamer (MidiDriver *target) :
_target (target),
_stream_proc (0),
_stream_param (0),
_mode (0),
_paused (false),
_event_count (0),
_event_index (0),
_tempo (500000), // 120 BPM = 500,000 microseconds between each beat
_ticks_per_beat (96),
_delay (0),
_active (false)
{ }
void MidiStreamer::set_stream_callback (void *param, StreamCallback *sc)
{
_stream_param = param;
_stream_proc = sc;
if (_mode) {
_event_count = _stream_proc (_stream_param, _events, ARRAYSIZE (_events));
_event_index = 0;
}
}
int MidiStreamer::timer_thread (void *param) {
MidiStreamer *mid = (MidiStreamer *) param;
int old_time, cur_time;
while (mid->_mode) {
g_system->delay_msecs (100);
while (!mid->_stream_proc);
old_time = g_system->get_msecs();
while (!mid->_paused) {
g_system->delay_msecs(10);
cur_time = g_system->get_msecs();
while (old_time < cur_time) {
old_time += 10;
mid->on_timer();
}
}
}
// Turn off all notes on all channels,
// just to catch anything still playing.
int i;
for (i = 0; i < 16; ++i)
mid->_target->send ((0x7B << 8) | 0xB0 | i);
mid->_active = false;
return 0;
}
void MidiStreamer::on_timer()
{
_delay += 10000;
while (true) {
if (_event_index >= _event_count) {
_event_count = _stream_proc (_stream_param, _events, ARRAYSIZE (_events));
_event_index = 0;
}
if (!_event_count)
return;
MidiEvent *ev = &_events [_event_index];
if (_delay < _tempo * (long) ev->delta / (long) _ticks_per_beat)
return;
_delay -= _tempo * ev->delta / _ticks_per_beat;
if ((ev->event >> 24) != ME_TEMPO) {
_target->send (ev->event);
} else {
_tempo = ev->event & 0xFFFFFF;
}
++_event_index;
} // end while
}
int MidiStreamer::open (int mode)
{
if (_mode != 0)
close();
int res = _target->open (MidiDriver::MO_SIMPLE);
if (res && res != MERR_ALREADY_OPEN)
return res;
// Wait for existing timer thread to shut down.
while (_active);
_event_index = _event_count = _delay = 0;
_mode = mode;
_paused = false;
_active = true;
if (mode == MO_SIMPLE)
return 0;
g_system->create_thread (timer_thread, this);
return 0;
}
void MidiStreamer::close()
{
if (!_mode)
return;
_mode = 0;
_paused = true;
}
uint32 MidiStreamer::property (int prop, uint32 param)
{
switch (prop) {
// 16-bit time division according to standard midi specification
case PROP_TIMEDIV:
_ticks_per_beat = (uint16)param;
return 1;
}
return 0;
}
|
