104 lines
3.2 KiB
C
104 lines
3.2 KiB
C
|
||
/*******************************************************************************/
|
||
/* Copyright (C) 2008 Jonathan Moore Liles */
|
||
/* */
|
||
/* 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; see the file COPYING. If not,write to the Free Software */
|
||
/* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */
|
||
/*******************************************************************************/
|
||
|
||
#include "../Control_Sequence.H"
|
||
|
||
#include "../Transport.H" // for ->frame
|
||
|
||
#include "util/Thread.H"
|
||
|
||
#include <list>
|
||
using std::list;
|
||
|
||
|
||
|
||
/**********/
|
||
/* Engine */
|
||
/**********/
|
||
|
||
static inline float
|
||
linear_interpolate ( float y1, float y2, float mu )
|
||
{
|
||
// return y1 + mu * ( y2 - y1 );
|
||
return y1 * ( 1.0f - mu ) + y2 * mu;
|
||
}
|
||
|
||
static inline float
|
||
sigmoid_interpolate ( float y1, float y2, float mu )
|
||
{
|
||
return linear_interpolate( y1, y2, ( 1 - cos( mu * M_PI ) ) / 2 );
|
||
}
|
||
|
||
|
||
|
||
/** fill buf with /nframes/ of interpolated control curve values
|
||
* starting at /frame/ */
|
||
nframes_t
|
||
Control_Sequence::play ( sample_t *buf, nframes_t frame, nframes_t nframes )
|
||
{
|
||
THREAD_ASSERT( RT );
|
||
|
||
Control_Point *p2, *p1 = (Control_Point*)&_widgets.front();
|
||
|
||
nframes_t n = nframes;
|
||
|
||
for ( list <Sequence_Widget *>::const_iterator i = _widgets.begin();
|
||
i != _widgets.end(); ++i, p1 = p2 )
|
||
{
|
||
p2 = (Control_Point*)(*i);
|
||
|
||
if ( p2->when() < frame )
|
||
continue;
|
||
|
||
/* do incremental linear interpolation */
|
||
|
||
const nframes_t len = p2->when() - p1->when();
|
||
|
||
/* scale to -1.0 to 1.0 */
|
||
const float y1 = 1.0f - ( 2.0f * p1->control() );
|
||
const float y2 = 1.0f - ( 2.0f * p2->control() );
|
||
|
||
const nframes_t start = frame - p1->when();
|
||
const float incr = ( y2 - y1 ) / (float)len;
|
||
|
||
float v = y1 + start * incr;
|
||
|
||
for ( nframes_t i = start; i < len && n--; ++i, v += incr )
|
||
*(buf++) = v;
|
||
|
||
}
|
||
|
||
return nframes - n;
|
||
}
|
||
|
||
nframes_t
|
||
Control_Sequence::process ( nframes_t nframes )
|
||
{
|
||
THREAD_ASSERT( RT );
|
||
|
||
if ( _output->connected() ) /* don't waste CPU on disconnected ports */
|
||
{
|
||
void *buf = _output->buffer( nframes );
|
||
|
||
return play( (sample_t*)buf, transport->frame, nframes );
|
||
}
|
||
else
|
||
return nframes;
|
||
}
|