C++ (Cpp) GeoDataCoordinates::interpolate示例

void PlaybackFlyToItem::center( double t )
{
    Q_ASSERT( t >= 0.0 && t <= 1.0 );
    Q_ASSERT( m_before );
    if ( m_flyTo->flyToMode() == GeoDataFlyTo::Bounce || !m_before->m_before || !m_next ) {
        GeoDataCoordinates const a = m_before->m_flyTo->view()->coordinates();
        GeoDataCoordinates const b = m_flyTo->view()->coordinates();
        emit centerOn( a.interpolate( b, t ) );
    } else {
        Q_ASSERT( m_flyTo->flyToMode() == GeoDataFlyTo::Smooth );
        GeoDataCoordinates const a = m_before->m_before->m_flyTo->view()->coordinates();
        GeoDataCoordinates const b = m_before->m_flyTo->view()->coordinates();
        GeoDataCoordinates const c = m_flyTo->view()->coordinates();
        GeoDataCoordinates const d = m_next->m_flyTo->view()->coordinates();
        emit centerOn( b.interpolate( a, c, d, t ) );
    }
}