66 lines
1.6 KiB
C++
66 lines
1.6 KiB
C++
|
|
// NES non-linear audio output handling.
|
|
|
|
// Nes_Snd_Emu 0.1.7. Copyright (C) 2003-2005 Shay Green. GNU LGPL license.
|
|
|
|
#ifndef NONLINEAR_BUFFER_H
|
|
#define NONLINEAR_BUFFER_H
|
|
|
|
#include "Multi_Buffer.h"
|
|
class Nes_Apu;
|
|
|
|
// Use to make samples non-linear in Blip_Buffer used for triangle, noise, and DMC only
|
|
class Nes_Nonlinearizer {
|
|
public:
|
|
Nes_Nonlinearizer();
|
|
|
|
// Must be called when buffer is cleared
|
|
void clear() { accum = 0x8000; }
|
|
|
|
// Enable/disable non-linear output
|
|
void enable( Nes_Apu&, bool = true );
|
|
|
|
// Make at most 'count' samples in buffer non-linear and return number
|
|
// of samples modified. This many samples must then be read out of the buffer.
|
|
long make_nonlinear( Blip_Buffer&, long count );
|
|
|
|
private:
|
|
enum { shift = 5 };
|
|
enum { half = 0x8000 >> shift };
|
|
enum { entry_mask = half * 2 - 1 };
|
|
BOOST::uint16_t table [half * 2];
|
|
long accum;
|
|
bool nonlinear;
|
|
};
|
|
|
|
class Nonlinear_Buffer : public Multi_Buffer {
|
|
public:
|
|
Nonlinear_Buffer();
|
|
~Nonlinear_Buffer();
|
|
|
|
// Enable/disable non-linear output
|
|
void enable_nonlinearity( Nes_Apu&, bool = true );
|
|
|
|
// Blip_Buffer to output other sound chips to
|
|
Blip_Buffer* buffer() { return &buf; }
|
|
|
|
// See Multi_Buffer.h
|
|
blargg_err_t sample_rate( long rate, int msec = blip_default_length );
|
|
using Multi_Buffer::sample_rate;
|
|
void clock_rate( long );
|
|
void bass_freq( int );
|
|
void clear();
|
|
channel_t channel( int );
|
|
void end_frame( blip_time_t, bool unused = true );
|
|
long samples_avail() const;
|
|
long read_samples( blip_sample_t*, long );
|
|
|
|
private:
|
|
Blip_Buffer buf;
|
|
Blip_Buffer tnd;
|
|
Nes_Nonlinearizer nonlinearizer;
|
|
};
|
|
|
|
#endif
|
|
|