scummvm/audio/mods/protracker.h
Coen Rampen caca2ea61f AUDIO: Make subclassing Module and ProtrackerStream easier
To implement a MOD variant for the Chewy engine, this commit makes some changes
to make subclassing of the ProtrackerStream and associated Module class easier.
2022-06-09 17:13:56 +02:00

153 lines
3.5 KiB
C++

/* 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 3 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, see <http://www.gnu.org/licenses/>.
*
*/
/**
* @file
* Sound decoder used in engines:
* - agos
* - parallaction
* - gob
* - hopkins
* - chewy (subclass)
*/
#ifndef AUDIO_MODS_PROTRACKER_H
#define AUDIO_MODS_PROTRACKER_H
#include "audio/mods/paula.h"
#include "audio/mods/module.h"
namespace Common {
class SeekableReadStream;
}
namespace Modules {
class ProtrackerStream : public ::Audio::Paula {
protected:
Module *_module;
private:
int _tick;
int _row;
int _pos;
int _speed;
int _bpm;
// For effect 0xB - Jump To Pattern;
bool _hasJumpToPattern;
int _jumpToPattern;
// For effect 0xD - PatternBreak;
bool _hasPatternBreak;
int _skipRow;
// For effect 0xE6 - Pattern Loop
bool _hasPatternLoop;
int _patternLoopCount;
int _patternLoopRow;
// For effect 0xEE - Pattern Delay
byte _patternDelay;
static const int16 sinetable[];
struct Track {
byte sample;
byte lastSample;
uint16 period;
Offset offset;
byte vol;
byte finetune;
// For effect 0x0 - Arpeggio
bool arpeggio;
byte arpeggioNotes[3];
// For effect 0x3 - Porta to note
uint16 portaToNote;
byte portaToNoteSpeed;
// For effect 0x4 - Vibrato
int vibrato;
byte vibratoPos;
byte vibratoSpeed;
byte vibratoDepth;
// For effect 0xED - Delay sample
byte delaySample;
byte delaySampleTick;
} _track[4];
public:
ProtrackerStream(Common::SeekableReadStream *stream, int offs, int rate, bool stereo);
protected:
ProtrackerStream(int rate, bool stereo);
public:
virtual ~ProtrackerStream();
Modules::Module *getModule() {
// Ordinarily, the Module is not meant to be seen outside of
// this class, but occasionally, it's useful to be able to
// manipulate it directly. The Hopkins engine uses this to
// repair a broken song.
return _module;
}
private:
void interrupt() override;
void doPorta(int track);
void doVibrato(int track);
void doVolSlide(int track, byte ex, byte ey);
void updateRow();
void updateEffects();
};
}
namespace Audio {
class AudioStream;
/*
* Factory function for ProTracker streams. Reads all data from the
* given ReadStream and creates an AudioStream from this. No reference
* to the 'stream' object is kept, so you can safely delete it after
* invoking this factory.
*
* @param stream the ReadStream from which to read the ProTracker data
* @param rate TODO
* @param stereo TODO
* @param module can be used to return the Module object (rarely useful)
* @return a new AudioStream, or NULL, if an error occurred
*/
AudioStream *makeProtrackerStream(Common::SeekableReadStream *stream, int offs = 0, int rate = 44100, bool stereo = true, Modules::Module **module = 0);
} // End of namespace Audio
#endif