overte-HifiExperiments/externals/stk/include/Mesh2D.h
2013-05-30 12:25:29 -07:00

144 lines
4.3 KiB
C++

#ifndef STK_MESH2D_H
#define STK_MESH2D_H
#include "Instrmnt.h"
#include "OnePole.h"
namespace stk {
/***************************************************/
/*! \class Mesh2D
\brief Two-dimensional rectilinear waveguide mesh class.
This class implements a rectilinear,
two-dimensional digital waveguide mesh
structure. For details, see Van Duyne and
Smith, "Physical Modeling with the 2-D Digital
Waveguide Mesh", Proceedings of the 1993
International Computer Music Conference.
This is a digital waveguide model, making its
use possibly subject to patents held by Stanford
University, Yamaha, and others.
Control Change Numbers:
- X Dimension = 2
- Y Dimension = 4
- Mesh Decay = 11
- X-Y Input Position = 1
by Julius Smith, 2000 - 2002.
Revised by Gary Scavone for STK, 2002.
*/
/***************************************************/
const unsigned short NXMAX = 12;
const unsigned short NYMAX = 12;
class Mesh2D : public Instrmnt
{
public:
//! Class constructor, taking the x and y dimensions in samples.
Mesh2D( unsigned short nX, unsigned short nY );
//! Class destructor.
~Mesh2D( void );
//! Reset and clear all internal state.
void clear( void );
//! Set the x dimension size in samples.
void setNX( unsigned short lenX );
//! Set the y dimension size in samples.
void setNY( unsigned short lenY );
//! Set the x, y input position on a 0.0 - 1.0 scale.
void setInputPosition( StkFloat xFactor, StkFloat yFactor );
//! Set the loss filters gains (0.0 - 1.0).
void setDecay( StkFloat decayFactor );
//! Impulse the mesh with the given amplitude (frequency ignored).
void noteOn( StkFloat frequency, StkFloat amplitude );
//! Stop a note with the given amplitude (speed of decay) ... currently ignored.
void noteOff( StkFloat amplitude );
//! Calculate and return the signal energy stored in the mesh.
StkFloat energy( void );
//! Input a sample to the mesh and compute one output sample.
StkFloat inputTick( StkFloat input );
//! Perform the control change specified by \e number and \e value (0.0 - 128.0).
void controlChange( int number, StkFloat value );
//! Compute and return one output sample.
StkFloat tick( unsigned int channel = 0 );
//! Fill a channel of the StkFrames object with computed outputs.
/*!
The \c channel argument must be less than the number of
channels in the StkFrames argument (the first channel is specified
by 0). However, range checking is only performed if _STK_DEBUG_
is defined during compilation, in which case an out-of-range value
will trigger an StkError exception.
*/
StkFrames& tick( StkFrames& frames, unsigned int channel = 0 );
protected:
StkFloat tick0();
StkFloat tick1();
void clearMesh();
unsigned short NX_, NY_;
unsigned short xInput_, yInput_;
OnePole filterX_[NXMAX];
OnePole filterY_[NYMAX];
StkFloat v_[NXMAX-1][NYMAX-1]; // junction velocities
StkFloat vxp_[NXMAX][NYMAX]; // positive-x velocity wave
StkFloat vxm_[NXMAX][NYMAX]; // negative-x velocity wave
StkFloat vyp_[NXMAX][NYMAX]; // positive-y velocity wave
StkFloat vym_[NXMAX][NYMAX]; // negative-y velocity wave
// Alternate buffers
StkFloat vxp1_[NXMAX][NYMAX]; // positive-x velocity wave
StkFloat vxm1_[NXMAX][NYMAX]; // negative-x velocity wave
StkFloat vyp1_[NXMAX][NYMAX]; // positive-y velocity wave
StkFloat vym1_[NXMAX][NYMAX]; // negative-y velocity wave
int counter_; // time in samples
};
inline StkFrames& Mesh2D :: tick( StkFrames& frames, unsigned int channel )
{
unsigned int nChannels = lastFrame_.channels();
#if defined(_STK_DEBUG_)
if ( channel > frames.channels() - nChannels ) {
oStream_ << "Mesh2D::tick(): channel and StkFrames arguments are incompatible!";
handleError( StkError::FUNCTION_ARGUMENT );
}
#endif
StkFloat *samples = &frames[channel];
unsigned int j, hop = frames.channels() - nChannels;
if ( nChannels == 1 ) {
for ( unsigned int i=0; i<frames.frames(); i++, samples += hop )
*samples++ = tick();
}
else {
for ( unsigned int i=0; i<frames.frames(); i++, samples += hop ) {
*samples++ = tick();
for ( j=1; j<nChannels; j++ )
*samples++ = lastFrame_[j];
}
}
return frames;
}
} // stk namespace
#endif