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Merge pull request #583 from diizy/bandlimit

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Monstro/Bandlimit updates
This commit is contained in:
Tobias Doerffel
2014-04-09 22:02:07 +02:00
parent 0068be62c0 2bfd19cc44
commit d3aff6e1fb
6 changed files with 100 additions and 86 deletions
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47
src/core/BandLimitedWave.cpp
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@@ -27,30 +27,35 @@
WaveMipMap BandLimitedWave::s_waveforms[4] = { };
bool BandLimitedWave::s_wavesGenerated = false;
void BandLimitedWave::generateWaves()
{
// don't generate if they already exist
if( s_wavesGenerated ) return;
int i;
// saw wave - BLSaw
for( i = 1; i <= MAXLEN; i++ )
for( i = 0; i <= MAXTBL; i++ )
{
const int len = 1 << i;
const double om = 1.0 / len;
const int len = TLENS[i];
//const double om = 1.0 / len;
double max = 0.0;
for( int ph = 0; ph < len; ph++ )
{
int harm = 1;
double s = 0.0f;
double hlen;
do
{
hlen = static_cast<double>( len ) / static_cast<double>( harm );
const double amp = -1.0 / static_cast<double>( harm );
const double a2 = cos( om * harm * F_2PI );
s += amp * a2 * sin( static_cast<double>( ph * harm ) / static_cast<double>( len ) * F_2PI );
//const double a2 = cos( om * harm * F_2PI );
s += amp * /*a2 **/sin( static_cast<double>( ph * harm ) / static_cast<double>( len ) * F_2PI );
harm++;
} while( len/harm > 2 );
} while( hlen >= 4.0 );
s_waveforms[ BandLimitedWave::BLSaw ].setSampleAt( i, ph, s );
max = qMax( max, qAbs( s ) );
}
@@ -63,23 +68,25 @@ void BandLimitedWave::generateWaves()
}
// square wave - BLSquare
for( i = 1; i <= MAXLEN; i++ )
for( i = 0; i <= MAXTBL; i++ )
{
const int len = 1 << i;
const double om = 1.0 / len;
const int len = TLENS[i];
//const double om = 1.0 / len;
double max = 0.0;
for( int ph = 0; ph < len; ph++ )
{
int harm = 1;
double s = 0.0f;
double hlen;
do
{
hlen = static_cast<double>( len ) / static_cast<double>( harm );
const double amp = 1.0 / static_cast<double>( harm );
const double a2 = cos( om * harm * F_2PI );
s += amp * a2 * sin( static_cast<double>( ph * harm ) / static_cast<double>( len ) * F_2PI );
//const double a2 = cos( om * harm * F_2PI );
s += amp * /*a2 **/ sin( static_cast<double>( ph * harm ) / static_cast<double>( len ) * F_2PI );
harm += 2;
} while( len/harm > 2 );
} while( hlen >= 4.0 );
s_waveforms[ BandLimitedWave::BLSquare ].setSampleAt( i, ph, s );
max = qMax( max, qAbs( s ) );
}
@@ -93,9 +100,9 @@ void BandLimitedWave::generateWaves()
// triangle wave - BLTriangle
for( i = 1; i <= MAXLEN; i++ )
for( i = 0; i <= MAXTBL; i++ )
{
const int len = 1 << i;
const int len = TLENS[i];
//const double om = 1.0 / len;
double max = 0.0;
@@ -103,14 +110,16 @@ void BandLimitedWave::generateWaves()
{
int harm = 1;
double s = 0.0f;
double hlen;
do
{
hlen = static_cast<double>( len ) / static_cast<double>( harm );
const double amp = 1.0 / static_cast<double>( harm * harm );
//const double a2 = cos( om * harm * F_2PI );
s += amp * /*a2 **/ sin( ( static_cast<double>( ph * harm ) / static_cast<double>( len ) +
( ( harm + 1 ) % 4 == 0 ? 0.5 : 0.0 ) ) * F_2PI );
harm += 2;
} while( len/harm > 2 );
} while( hlen >= 4.0 );
s_waveforms[ BandLimitedWave::BLTriangle ].setSampleAt( i, ph, s );
max = qMax( max, qAbs( s ) );
}
@@ -125,9 +134,9 @@ void BandLimitedWave::generateWaves()
// moog saw wave - BLMoog
// basically, just add in triangle + 270-phase saw
for( i = 1; i <= MAXLEN; i++ )
for( i = 0; i <= MAXTBL; i++ )
{
const int len = 1 << i;
const int len = TLENS[i];
for( int ph = 0; ph < len; ph++ )
{
@@ -138,4 +147,6 @@ void BandLimitedWave::generateWaves()
}
}
s_wavesGenerated = true;
}

4
src/core/main.cpp
View File

@@ -65,7 +65,6 @@
#include "ProjectRenderer.h"
#include "DataFile.h"
#include "song.h"
#include "BandLimitedWave.h"
static inline QString baseName( const QString & _file )
{
@@ -120,9 +119,6 @@ int main( int argc, char * * argv )
new QCoreApplication( argc, argv ) :
new QApplication( argc, argv ) ;
// generate bandlimited wavetables for instruments to use
BandLimitedWave::generateWaves();
Mixer::qualitySettings qs( Mixer::qualitySettings::Mode_HighQuality );
ProjectRenderer::OutputSettings os( 44100, false, 160,
ProjectRenderer::Depth_16Bit );