aboutsummaryrefslogtreecommitdiff
path: root/engines/scumm/player_mod.cpp
blob: 6411f0a17a5496f0f26ced410b078896ee7478f9 (plain)
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
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
/* ScummVM - Graphic Adventure Engine
 *
 * ScummVM is the legal property of its developers, whose names
 * are too numerous to list here. Please refer to the COPYRIGHT
 * file distributed with this source distribution.
 *
 * 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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
 *
 */


#include "scumm/player_mod.h"
#include "audio/mixer.h"
#include "audio/rate.h"
#include "audio/decoders/raw.h"

namespace Scumm {

Player_MOD::Player_MOD(Audio::Mixer *mixer)
	: _mixer(mixer), _sampleRate(mixer->getOutputRate()) {
	int i;
	_mixamt = 0;
	_mixpos = 0;

	for (i = 0; i < MOD_MAXCHANS; i++) {
		_channels[i].id = 0;
		_channels[i].vol = 0;
		_channels[i].freq = 0;
		_channels[i].input = NULL;
		_channels[i].ctr = 0;
		_channels[i].pos = 0;
	}

	_playproc = NULL;
	_playparam = NULL;

	_mixer->playStream(Audio::Mixer::kPlainSoundType, &_soundHandle, this, -1, Audio::Mixer::kMaxChannelVolume, 0, DisposeAfterUse::NO, true);
}

Player_MOD::~Player_MOD() {
	_mixer->stopHandle(_soundHandle);
	for (int i = 0; i < MOD_MAXCHANS; i++) {
		if (!_channels[i].id)
			continue;
		delete _channels[i].input;
	}
}

void Player_MOD::setMusicVolume(int vol) {
	_maxvol = vol;
}

void Player_MOD::setUpdateProc(ModUpdateProc *proc, void *param, int freq) {
	_playproc = proc;
	_playparam = param;
	_mixamt = _sampleRate / freq;
}
void Player_MOD::clearUpdateProc() {
	_playproc = NULL;
	_playparam = NULL;
	_mixamt = 0;
}

void Player_MOD::startChannel(int id, void *data, int size, int rate, uint8 vol, int loopStart, int loopEnd, int8 pan) {
	int i;
	if (id == 0)
		error("player_mod - attempted to start channel id 0");

	for (i = 0; i < MOD_MAXCHANS; i++) {
		if (!_channels[i].id)
			break;
	}
	if (i == MOD_MAXCHANS) {
		warning("player_mod - too many music channels playing (%i max)",MOD_MAXCHANS);
		return;
	}
	_channels[i].id = id;
	_channels[i].vol = vol;
	_channels[i].pan = pan;
	_channels[i].freq = rate;
	_channels[i].ctr = 0;

	Audio::SeekableAudioStream *stream = Audio::makeRawStream((const byte *)data, size, rate, 0);
	if (loopStart != loopEnd) {
		_channels[i].input = new Audio::SubLoopingAudioStream(stream, 0, Audio::Timestamp(0, loopStart, rate), Audio::Timestamp(0, loopEnd, rate));
	} else {
		_channels[i].input = stream;
	}

	// read the first sample
	_channels[i].input->readBuffer(&_channels[i].pos, 1);
}

void Player_MOD::stopChannel(int id) {
	if (id == 0)
		error("player_mod - attempted to stop channel id 0");
	for (int i = 0; i < MOD_MAXCHANS; i++) {
		if (_channels[i].id == id) {
			delete _channels[i].input;
			_channels[i].input = NULL;
			_channels[i].id = 0;
			_channels[i].vol = 0;
			_channels[i].freq = 0;
			_channels[i].ctr = 0;
			_channels[i].pos = 0;
		}
	}
}
void Player_MOD::setChannelVol(int id, uint8 vol) {
	if (id == 0)
		error("player_mod - attempted to set volume for channel id 0");
	for (int i = 0; i < MOD_MAXCHANS; i++) {
		if (_channels[i].id == id) {
			_channels[i].vol = vol;
			break;
		}
	}
}

void Player_MOD::setChannelPan(int id, int8 pan) {
	if (id == 0)
		error("player_mod - attempted to set pan for channel id 0");
	for (int i = 0; i < MOD_MAXCHANS; i++) {
		if (_channels[i].id == id) {
			_channels[i].pan = pan;
			break;
		}
	}
}

void Player_MOD::setChannelFreq(int id, int freq) {
	if (id == 0)
		error("player_mod - attempted to set frequency for channel id 0");
	for (int i = 0; i < MOD_MAXCHANS; i++) {
		if (_channels[i].id == id) {
			if (freq > 31400)	// this is about as high as WinUAE goes
				freq = 31400;	// can't easily verify on my own Amiga
			_channels[i].freq = freq;
			break;
		}
	}
}

void Player_MOD::do_mix(int16 *data, uint len) {
	int i;
	int dpos = 0;
	uint dlen = 0;
	memset(data, 0, 2 * len * sizeof(int16));
	while (len) {
		if (_playproc) {
			dlen = _mixamt - _mixpos;
			if (!_mixpos)
				_playproc(_playparam);
			if (dlen <= len) {
				_mixpos = 0;
				len -= dlen;
			} else {
				_mixpos = len;
				dlen = len;
				len = 0;
			}
		} else {
			dlen = len;
			len = 0;
		}
		for (i = 0; i < MOD_MAXCHANS; i++) {
			if (_channels[i].id) {
				Audio::st_volume_t vol_l = (127 - _channels[i].pan) * _channels[i].vol / 127;
				Audio::st_volume_t vol_r = (127 + _channels[i].pan) * _channels[i].vol / 127;
				for (uint j = 0; j < dlen; j++) {
					// simple linear resample, unbuffered
					int delta = (uint32)(_channels[i].freq * 0x10000) / _sampleRate;
					uint16 cfrac = ~_channels[i].ctr & 0xFFFF;
					if (_channels[i].ctr + delta < 0x10000)
						cfrac = delta;
					_channels[i].ctr += delta;
					int32 cpos = _channels[i].pos * cfrac / 0x10000;
					while (_channels[i].ctr >= 0x10000) {
						if (_channels[i].input->readBuffer(&_channels[i].pos, 1) != 1) {	// out of data
							stopChannel(_channels[i].id);
							goto skipchan;	// exit 2 loops at once
						}
						_channels[i].ctr -= 0x10000;
						if (_channels[i].ctr > 0x10000)
							cpos += _channels[i].pos;
						else
							cpos += (int32)(_channels[i].pos * (_channels[i].ctr & 0xFFFF)) / 0x10000;
					}
					int16 pos = 0;
					// if too many samples play in a row, the calculation below will overflow and clip
					// so try and split it up into pieces it can manage comfortably
					while (cpos < -0x8000) {
						pos -= 0x80000000 / delta;
						cpos += 0x8000;
					}
					while (cpos > 0x7FFF) {
						pos += 0x7FFF0000 / delta;
						cpos -= 0x7FFF;
					}
					pos += cpos * 0x10000 / delta;
					Audio::clampedAdd(data[(dpos + j) * 2 + 0], pos * vol_l / Audio::Mixer::kMaxMixerVolume);
					Audio::clampedAdd(data[(dpos + j) * 2 + 1], pos * vol_r / Audio::Mixer::kMaxMixerVolume);
				}
			}
skipchan:		;	// channel ran out of data
		}
		dpos += dlen;
	}
}

} // End of namespace Scumm