97 lines
2.5 KiB
C++
97 lines
2.5 KiB
C++
/* REminiscence - Flashback interpreter
|
|
* Copyright (C) 2005-2007 Gregory Montoir
|
|
*
|
|
* 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.
|
|
*/
|
|
|
|
#ifndef __MIXER_H__
|
|
#define __MIXER_H__
|
|
|
|
#include "intern.h"
|
|
|
|
struct MixerChunk {
|
|
uint8 *data;
|
|
uint32 len;
|
|
|
|
int8 getPCM(int offset) const {
|
|
if (offset < 0) {
|
|
offset = 0;
|
|
} else if (offset >= (int)len) {
|
|
offset = len - 1;
|
|
}
|
|
return (int8)data[offset];
|
|
}
|
|
};
|
|
|
|
struct MixerChannel {
|
|
uint8 active;
|
|
uint8 volume;
|
|
MixerChunk chunk;
|
|
uint32 chunkPos;
|
|
uint32 chunkInc;
|
|
};
|
|
|
|
struct SystemStub;
|
|
|
|
struct Mixer {
|
|
typedef bool (*PremixHook)(void *userData, int16 *buf, int len);
|
|
|
|
enum {
|
|
NUM_CHANNELS = 4,
|
|
FRAC_BITS = 12,
|
|
MAX_VOLUME = 64,
|
|
MIX_AMPLIFICATIION = 64 // TODO: edit here to tweak sound
|
|
};
|
|
|
|
void *_mutex;
|
|
SystemStub *_stub;
|
|
MixerChannel _channels[NUM_CHANNELS];
|
|
PremixHook _premixHook;
|
|
void *_premixHookData;
|
|
|
|
Mixer(SystemStub *stub);
|
|
void init();
|
|
void free();
|
|
void setPremixHook(PremixHook premixHook, void *userData);
|
|
void play(const MixerChunk *mc, uint16 freq, uint8 volume);
|
|
void stopAll();
|
|
uint32 getSampleRate() const;
|
|
void mix(int8 *buf, int len);
|
|
|
|
//static void addclamp(int16 &a, int b);
|
|
static void mixCallback(void *param, uint8 *buf, int len);
|
|
};
|
|
|
|
template <class T>
|
|
int resampleLinear(T *sample, int pos, int step, int fracBits) {
|
|
const int inputPos = pos >> fracBits;
|
|
const int inputFrac = (1 << fracBits) - 1;
|
|
int out = sample->getPCM(inputPos);
|
|
out += (sample->getPCM(inputPos + 1) - out) * inputFrac >> fracBits;
|
|
return out;
|
|
}
|
|
|
|
template <class T>
|
|
int resample3Pt(T *sample, int pos, int step, int fracBits) {
|
|
const int inputPos = pos >> fracBits;
|
|
const int inputFrac = (1 << fracBits) - 1;
|
|
int out = sample->getPCM(inputPos) >> 1;
|
|
out += sample->getPCM(inputPos + ((inputFrac - (step >> 1)) >> fracBits)) >> 2;
|
|
out += sample->getPCM(inputPos + ((inputFrac + (step >> 1)) >> fracBits)) >> 2;
|
|
return out;
|
|
}
|
|
|
|
#endif // __MIXER_H__
|