Method paintEvent

src/tracks/SampleTrack.cpp:478–573

void SampleTCOView::paintEvent( QPaintEvent * pe )
{
	QPainter painter( this );

	if( !needsUpdate() )
	{
		painter.drawPixmap( 0, 0, m_paintPixmap );
		return;
	}

	setNeedsUpdate( false );

	m_paintPixmap = m_paintPixmap.isNull() == true || m_paintPixmap.size() != size()
		? QPixmap( size() ) : m_paintPixmap;

	QPainter p( &m_paintPixmap );

	QLinearGradient lingrad( 0, 0, 0, height() );
	QColor c;
	bool muted = m_tco->getTrack()->isMuted() || m_tco->isMuted();

	// state: selected, muted, normal
	c = isSelected() ? selectedColor() : ( muted ? mutedBackgroundColor()
		: painter.background().color() );

	lingrad.setColorAt( 1, c.darker( 300 ) );
	lingrad.setColorAt( 0, c );

	// paint a black rectangle under the pattern to prevent glitches with transparent backgrounds
	p.fillRect( rect(), QColor( 0, 0, 0 ) );

	if( gradient() )
	{
		p.fillRect( rect(), lingrad );
	}
	else
	{
		p.fillRect( rect(), c );
	}

	p.setPen( !muted ? painter.pen().brush().color() : mutedColor() );

	const int spacing = TCO_BORDER_WIDTH + 1;
	const float ppt = fixedTCOs() ?
			( parentWidget()->width() - 2 * TCO_BORDER_WIDTH )
					/ (float) m_tco->length().getTact() :
								pixelsPerTact();

	float nom = Engine::getSong()->getTimeSigModel().getNumerator();
	float den = Engine::getSong()->getTimeSigModel().getDenominator();
	float ticksPerTact = DefaultTicksPerTact * nom / den;

	QRect r = QRect( TCO_BORDER_WIDTH, spacing,
			qMax( static_cast<int>( m_tco->sampleLength() * ppt / ticksPerTact ), 1 ), rect().bottom() - 2 * spacing );
	m_tco->m_sampleBuffer->visualize( p, r, pe->rect() );

	// disable antialiasing for borders, since its not needed
	p.setRenderHint( QPainter::Antialiasing, false );