cog/Frameworks/GME/gme/Multi_Buffer.h

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// Multi-channel sound buffer interface, and basic mono and stereo buffers
// Blip_Buffer $vers
#ifndef MULTI_BUFFER_H
#define MULTI_BUFFER_H
#include "blargg_common.h"
#include "Blip_Buffer.h"
// Interface to one or more Blip_Buffers mapped to one or more channels
// consisting of left, center, and right buffers.
class Multi_Buffer {
public:
// 1=mono, 2=stereo
Multi_Buffer( int samples_per_frame );
virtual ~Multi_Buffer() { }
// Sets the number of channels available and optionally their types
// (type information used by Effects_Buffer)
enum { type_index_mask = 0xFF };
enum { wave_type = 0x100, noise_type = 0x200, mixed_type = wave_type | noise_type };
virtual blargg_err_t set_channel_count( int, int const types [] = NULL );
int channel_count() const { return channel_count_; }
// Gets indexed channel, from 0 to channel_count()-1
struct channel_t {
Blip_Buffer* center;
Blip_Buffer* left;
Blip_Buffer* right;
};
virtual channel_t channel( int index ) BLARGG_PURE( ; )
// Number of samples per output frame (1 = mono, 2 = stereo)
int samples_per_frame() const;
// Count of changes to channel configuration. Incremented whenever
// a change is made to any of the Blip_Buffers for any channel.
unsigned channels_changed_count() { return channels_changed_count_; }
// See Blip_Buffer.h
virtual blargg_err_t set_sample_rate( int rate, int msec = blip_default_length ) BLARGG_PURE( ; )
int sample_rate() const;
int length() const;
virtual void clock_rate( int ) BLARGG_PURE( ; )
virtual void bass_freq( int ) BLARGG_PURE( ; )
virtual void clear() BLARGG_PURE( ; )
virtual void end_frame( blip_time_t ) BLARGG_PURE( ; )
virtual int read_samples( blip_sample_t [], int ) BLARGG_PURE( ; )
virtual int samples_avail() const BLARGG_PURE( ; )
private:
// noncopyable
Multi_Buffer( const Multi_Buffer& );
Multi_Buffer& operator = ( const Multi_Buffer& );
// Implementation
public:
BLARGG_DISABLE_NOTHROW
void disable_immediate_removal() { immediate_removal_ = false; }
protected:
bool immediate_removal() const { return immediate_removal_; }
int const* channel_types() const { return channel_types_; }
void channels_changed() { channels_changed_count_++; }
private:
unsigned channels_changed_count_;
int sample_rate_;
int length_;
int channel_count_;
int const samples_per_frame_;
int const* channel_types_;
bool immediate_removal_;
};
// Uses a single buffer and outputs mono samples.
class Mono_Buffer : public Multi_Buffer {
public:
// Buffer used for all channels
Blip_Buffer* center() { return &buf; }
// Implementation
public:
Mono_Buffer();
~Mono_Buffer();
virtual blargg_err_t set_sample_rate( int rate, int msec = blip_default_length );
virtual void clock_rate( int rate ) { buf.clock_rate( rate ); }
virtual void bass_freq( int freq ) { buf.bass_freq( freq ); }
virtual void clear() { buf.clear(); }
virtual int samples_avail() const { return buf.samples_avail(); }
virtual int read_samples( blip_sample_t p [], int s ) { return buf.read_samples( p, s ); }
virtual channel_t channel( int ) { return chan; }
virtual void end_frame( blip_time_t t ) { buf.end_frame( t ); }
private:
Blip_Buffer buf;
channel_t chan;
};
class Tracked_Blip_Buffer : public Blip_Buffer {
public:
// Non-zero if buffer still has non-silent samples in it. Requires that you call
// set_modified() appropriately.
unsigned non_silent() const;
// remove_samples( samples_avail() )
void remove_all_samples();
// Implementation
public:
BLARGG_DISABLE_NOTHROW
int read_samples( blip_sample_t [], int );
void remove_silence( int );
void remove_samples( int );
Tracked_Blip_Buffer();
void clear();
void end_frame( blip_time_t );
private:
int last_non_silence;
delta_t unsettled() const { return integrator() >> delta_bits; }
void remove_( int );
};
class Stereo_Mixer {
public:
Tracked_Blip_Buffer* bufs [3];
int samples_read;
Stereo_Mixer() : samples_read( 0 ) { }
void read_pairs( blip_sample_t out [], int count );
private:
void mix_mono ( blip_sample_t out [], int pair_count );
void mix_stereo( blip_sample_t out [], int pair_count );
};
// Uses three buffers (one for center) and outputs stereo sample pairs.
class Stereo_Buffer : public Multi_Buffer {
public:
// Buffers used for all channels
Blip_Buffer* center() { return &bufs [2]; }
Blip_Buffer* left() { return &bufs [0]; }
Blip_Buffer* right() { return &bufs [1]; }
// Implementation
public:
Stereo_Buffer();
~Stereo_Buffer();
virtual blargg_err_t set_sample_rate( int, int msec = blip_default_length );
virtual void clock_rate( int );
virtual void bass_freq( int );
virtual void clear();
virtual channel_t channel( int ) { return chan; }
virtual void end_frame( blip_time_t );
virtual int samples_avail() const { return (bufs [0].samples_avail() - mixer.samples_read) * 2; }
virtual int read_samples( blip_sample_t [], int );
private:
enum { bufs_size = 3 };
typedef Tracked_Blip_Buffer buf_t;
buf_t bufs [bufs_size];
Stereo_Mixer mixer;
channel_t chan;
int samples_avail_;
};
// Silent_Buffer generates no samples, useful where no sound is wanted
class Silent_Buffer : public Multi_Buffer {
channel_t chan;
public:
Silent_Buffer();
virtual blargg_err_t set_sample_rate( int rate, int msec = blip_default_length );
virtual void clock_rate( int ) { }
virtual void bass_freq( int ) { }
virtual void clear() { }
virtual channel_t channel( int ) { return chan; }
virtual void end_frame( blip_time_t ) { }
virtual int samples_avail() const { return 0; }
virtual int read_samples( blip_sample_t [], int ) { return 0; }
};
inline blargg_err_t Multi_Buffer::set_sample_rate( int rate, int msec )
{
sample_rate_ = rate;
length_ = msec;
return blargg_ok;
}
inline int Multi_Buffer::samples_per_frame() const { return samples_per_frame_; }
inline int Multi_Buffer::sample_rate() const { return sample_rate_; }
inline int Multi_Buffer::length() const { return length_; }
inline void Multi_Buffer::clock_rate( int ) { }
inline void Multi_Buffer::bass_freq( int ) { }
inline void Multi_Buffer::clear() { }
inline void Multi_Buffer::end_frame( blip_time_t ) { }
inline int Multi_Buffer::read_samples( blip_sample_t [], int ) { return 0; }
inline int Multi_Buffer::samples_avail() const { return 0; }
inline blargg_err_t Multi_Buffer::set_channel_count( int n, int const types [] )
{
channel_count_ = n;
channel_types_ = types;
return blargg_ok;
}
inline blargg_err_t Silent_Buffer::set_sample_rate( int rate, int msec )
{
return Multi_Buffer::set_sample_rate( rate, msec );
}
#endif