SCurvedHistogram.cpp

/* ***** BEGIN LICENSE BLOCK *****
 * FW4SPL - Copyright (C) IRCAD, 2009-2018.
 * Distributed under the terms of the GNU Lesser General Public License (LGPL) as
 * published by the Free Software Foundation.
 * ****** END LICENSE BLOCK ****** */

#include "scene2D/adaptor/SCurvedHistogram.hpp"

#include <fwData/Float.hpp>
#include <fwData/Histogram.hpp>
#include <fwData/mt/ObjectReadLock.hpp>
#include <fwData/Point.hpp>

#include <fwRenderQt/bspline.hpp>
#include <fwRenderQt/data/InitQtPen.hpp>
#include <fwRenderQt/Scene2DGraphicsView.hpp>

#include <fwServices/macros.hpp>

#include <QGraphicsRectItem>
#include <QGraphicsView>

fwServicesRegisterMacro( ::fwRenderQt::IAdaptor, ::scene2D::adaptor::SCurvedHistogram);

#define PI 3.14159265

namespace scene2D
{

namespace adaptor
{

static const ::fwServices::IService::KeyType s_POINT_INOUT     = "point";
static const ::fwServices::IService::KeyType s_HISTOGRAM_INPUT = "histogram";

const float SCurvedHistogram::SCALE            = 1.1f; // vertical scaling factor applied at each mouse scroll
const float SCurvedHistogram::NB_POINTS_BEZIER = 100.0f;

//-----------------------------------------------------------------------------------------------------------------

SCurvedHistogram::SCurvedHistogram() noexcept :
    m_painterPath(nullptr),
    m_borderWidth(1.75f),
    m_scale(1.0f),
    m_layer(nullptr)
{
}

//-----------------------------------------------------------------------------------------------------------------

SCurvedHistogram::~SCurvedHistogram() noexcept
{
}

//-----------------------------------------------------------------------------------------------------------------

void SCurvedHistogram::configuring()
{
    this->configureParams();  // Looks for 'xAxis', 'yAxis', 'opacity' and 'zValue'

    const ConfigType config = this->getConfigTree().get_child("config.<xmlattr>");

    m_innerColor  = QPen( Qt::transparent );
    m_borderColor = QPen( Qt::transparent );
    m_brush       = QBrush( Qt::NoBrush );

    if (config.count("borderColor"))
    {
        ::fwRenderQt::data::InitQtPen::setPenColor(
            m_borderColor, config.get<std::string>("borderColor"), m_opacity );
    }

    if (config.count("innerColor"))
    {
        ::fwRenderQt::data::InitQtPen::setPenColor(
            m_innerColor, config.get<std::string>("innerColor"), m_opacity );
    }

    if (config.count("borderWidth"))
    {
        m_borderWidth = config.get<float>("borderWidth");
    }
}

//----------------------------------------------------------------------------------------------------------

void SCurvedHistogram::starting()
{
    // Init border style
    m_borderColor.setCosmetic( true );
    m_borderColor.setWidthF( static_cast<qreal>(m_borderWidth) );
    m_borderColor.setStyle( Qt::SolidLine );
    m_borderColor.setJoinStyle( Qt::RoundJoin );
    m_borderColor.setCapStyle( Qt::RoundCap );

    m_brush = QBrush( m_innerColor.color() );

    this->updating();
}

//----------------------------------------------------------------------------------------------------------

SCurvedHistogram::Points SCurvedHistogram::getControlPoints(const ::fwData::Histogram::csptr& _histogram) const
{
    ::fwData::Histogram::fwHistogramValues histogramValues = _histogram->getValues();
    const float binsWidth    = _histogram->getBinsWidth();
    const float histogramMin = _histogram->getMinValue();

    Point p;
    Points controlPoints;
    const size_t nbValues = histogramValues.size();

    // WARNING: we shouldn't add all the points of the histogram into the vector of controlPoints
    // (testing...)
    for(size_t i = 0; i < nbValues; ++i)
    {
        p.first  = static_cast<double>(histogramMin + i * binsWidth);
        p.second = histogramValues[i];

        controlPoints.push_back( p );
    }

    return controlPoints;
}

//----------------------------------------------------------------------------------------------------------

SCurvedHistogram::Points SCurvedHistogram::getBSplinePoints( const Points& _points ) const
{
    Points bSplinePoints;
    point_list list;        // see bspline.h

    // Add again the first point with a higher value in order to prevent B-Spline algorithm from removing
    // the first value.
    list.add_point(new point(static_cast<float>( _points[0].first), static_cast<float>( _points[0].second * 2) ));

    // Add all the points
    for(const auto& pt : _points )
    {
        list.add_point(new point(static_cast<float>(pt.first), static_cast<float>(pt.second) ));
    }

    // Add again the last point
    list.add_point(new point(static_cast<float>( _points.back().first),
                             static_cast<float>( _points.back().second / 2 ) ));

    // Commpute the points of the B-Spline with external code from AHO (to be integrated here later).
    cat_curve curve( list );
    curve.m_precision = static_cast<int>(_points.size() * 5);
    curve.compute();

    for(int i = 0; i < curve.m_precision; ++i)
    {
        bSplinePoints.push_back( Point( curve.m_curve_point[i].x, curve.m_curve_point[i].y ) );
    }

    return bSplinePoints;
}

//----------------------------------------------------------------------------------------------------------

SCurvedHistogram::Points SCurvedHistogram::getResampledBSplinePoints(const Points& _bSplinePoints ) const
{
    Points points;
    Point point = _bSplinePoints.front();

    double dx, dy;
    const double maxLength = 2000;
    double segmentLength   = 0;

    points.push_back( point );

    for(Points::const_iterator it = _bSplinePoints.begin() + 1; it != _bSplinePoints.end(); ++it)
    {
        dx = abs((*it).first - point.first);    // theoretically positive
        dy = abs((*it).second - point.second);

        segmentLength += sqrt( dx * dx + dy * dy );

        if(segmentLength > maxLength)
        {
            points.push_back( *it );
            segmentLength = 0;
        }

        point = *it;
    }

    points.push_back( _bSplinePoints.back() );

    OSLM_TRACE("B-Spline points size moved from " << _bSplinePoints.size() << " to " << points.size());

    return points;
}

//----------------------------------------------------------------------------------------------------------

void SCurvedHistogram::computePointToPathLengthMapFromBSplinePoints(Points& _bSplinePoints )
{
    Points::iterator it = _bSplinePoints.begin();

    if( it != _bSplinePoints.end())
    {
        Point p;

        p = this->mapAdaptorToScene( *it, m_xAxis, m_yAxis );
        QPointF prevPt = QPointF(p.first,  p.second);
        m_painterPath->lineTo( p.first, p.second );
        qreal len = m_painterPath->length();
        ++it;

        for(; it != _bSplinePoints.end(); ++it)
        {
            p = this->mapAdaptorToScene( *it, m_xAxis, m_yAxis );

            m_painterPath->lineTo( p.first, p.second );

            // This is way too slow as the complexity is O(N.log(N) )
            //m_positionsToPathLength[ (int) p.first ] = m_painterPath->length();

            QPointF pt(p.first,  p.second);
            len                                                   += QLineF( prevPt, pt ).length();
            m_positionsToPathLength[ static_cast<int>( p.first ) ] = len;

            prevPt = pt;
        }
    }
}

//----------------------------------------------------------------------------------------------------------

void SCurvedHistogram::updating()
{
    this->stopping();

    const ::fwData::Histogram::csptr histogram = this->getInput< ::fwData::Histogram>(s_HISTOGRAM_INPUT);

    ::fwData::mt::ObjectReadLock lock(histogram);

    m_layer = new QGraphicsItemGroup();

    m_painterPath = new QPainterPath();

    if (!histogram->getValues().empty())
    {
        Points controlPoints = this->getControlPoints( histogram );
        Points bSplinePoints = this->getBSplinePoints( controlPoints );

        this->computePointToPathLengthMapFromBSplinePoints( bSplinePoints );

        // Try to remove unnecessary points of the B-Spline points
        Points resampledBSplinePoints = this->getResampledBSplinePoints( bSplinePoints );
        bSplinePoints = resampledBSplinePoints;

        this->buildBSplineFromPoints( bSplinePoints );

        // Adjust the layer's position and zValue depending on the associated axis
        m_layer->setPos(static_cast<qreal>( m_xAxis->getOrigin() ), static_cast<qreal>( m_yAxis->getOrigin() ));
        m_layer->setZValue(static_cast<qreal>( m_zValue ));

        // Add to the scene the unique item which gather the whole set of rectangle graphic items:
        this->getScene2DRender()->getScene()->addItem( m_layer );
    }
}

//----------------------------------------------------------------------------------------------------------

void SCurvedHistogram::buildBSplineFromPoints(Points& _bSplinePoints )
{
    const ::fwData::Histogram::csptr histogram = this->getInput< ::fwData::Histogram>(s_HISTOGRAM_INPUT);

    const bool useBorderColor = (m_borderColor.color() != Qt::transparent);
    const bool useInnerColor  = (m_innerColor.color() != Qt::transparent);

    Point currentPoint = this->mapAdaptorToScene( Point(histogram->getMinValue(), _bSplinePoints[0].second),
                                                  m_xAxis, m_yAxis );
    Point previousPoint = currentPoint;
    Points::iterator it;

    const QPointF startPoint( currentPoint.first, currentPoint.second / 10 );   // divide by 10 to cut meaningless
                                                                                // values
    QPainterPath path( QPointF(startPoint.x(), 0.0) );
    path.lineTo( startPoint );

    previousPoint.first  = startPoint.x();
    previousPoint.second = startPoint.y();

    // Build the path with the B-Spline points
    for(it = _bSplinePoints.begin() + 1; it != _bSplinePoints.end(); ++it)
    {
        currentPoint = this->mapAdaptorToScene(*it, m_xAxis, m_yAxis );

        path.lineTo( currentPoint.first, currentPoint.second );
    }

    // Close the path:
    m_painterPath->lineTo( static_cast<qreal>( histogram->getMaxValue() ), _bSplinePoints.back().second);

    if( useBorderColor )
    {
        path.lineTo( currentPoint.first, 0.0 );
        this->addBorderItem( path );
    }

    if( useInnerColor )
    {
        path.lineTo( previousPoint.first, 0.0 );
        this->addInnerItem( path );
    }
}

//----------------------------------------------------------------------------------------------------------

void SCurvedHistogram::addInnerItem( const QPainterPath& _path )
{
    QGraphicsPathItem* item = new QGraphicsPathItem( _path );
    item->setPen( Qt::NoPen );
    item->setBrush( m_brush );
    item->setPath( _path );
    item->setCacheMode( QGraphicsItem::DeviceCoordinateCache );
    item->setZValue(1);

    m_layer->addToGroup( item );
}

//----------------------------------------------------------------------------------------------------------

void SCurvedHistogram::addBorderItem( const QPainterPath& _path )
{
    QGraphicsPathItem* item = new QGraphicsPathItem( _path );
    item->setPen( m_borderColor );
    item->setBrush( Qt::NoBrush );
    item->setPath( _path );
    item->setCacheMode( QGraphicsItem::DeviceCoordinateCache );
    item->setZValue(2);

    m_layer->addToGroup( item );
}

//----------------------------------------------------------------------------------------------------------

SCurvedHistogram::Points SCurvedHistogram::quadraticInterpolation(
    const Point _p0, const Point _p1, const Point _p2 )
{
    Points points;
    Point p;

    const double d2 =
        2 * ((_p2.second - _p1.second) / (_p2.first - _p1.first) - (_p1.second - _p0.second)
             / (_p1.first - _p0.first))
        / (_p2.first - _p0.first);

    const double d1 = (_p2.second - _p1.second) / (_p2.first - _p1.first) - 0.5 * d2 * (_p2.first - _p1.first);
    const double d0 = _p1.second;

    points.push_back( _p0 );

    for(double x = _p0.first; x < _p2.first; x += 0.5)
    {
        p.first  = x;
        p.second = 0.5 * d2 * pow(x - _p1.first, 2) + d1 * (x - _p1.first) + d0;

        points.push_back( p );
    }

    return points;
}

//----------------------------------------------------------------------------------------------------------

SCurvedHistogram::Points SCurvedHistogram::cosinusInterpolation(const Point _p0, const Point _p1)
{
    Points points;
    Point p;
    double mu2;
    const double deltaX = _p1.first - _p0.first;

    for(double mu = 0.0; mu < 1.0; mu += 0.05)
    {
        mu2 = (1 - std::cos(mu * PI)) / 2;

        p.first  = _p0.first + mu * deltaX;
        p.second = _p0.second * (1 - mu2) + _p1.second * mu2;

        points.push_back( p );
    }

    return points;
}

//----------------------------------------------------------------------------------------------------------

SCurvedHistogram::Points SCurvedHistogram::cubicInterpolation(
    const Point _p0, const Point _p1, const Point _p2, const Point _p3 )
{
    Points points;
    Point p;
    double a0, a1, a2, a3, mu2;
    const double deltaX = _p2.first - _p1.first;
    for(double mu = 0.0; mu < 1.0; mu += 0.01)
    {
        mu2 = mu * mu;

        /*
           a0 = _p3.second - _p2.second - _p0.second + _p1.second;
           a1 = _p0.second - _p1.second - a0;
           a2 = _p2.second - _p0.second;
           a3 = _p1.second;
         */

        // Smoother curves (Catmull-Rom s_plines)
        a0 = -0.5*_p0.second + 1.5*_p1.second - 1.5*_p2.second + 0.5*_p3.second;
        a1 = _p0.second - 2.5*_p1.second + 2*_p2.second - 0.5*_p3.second;
        a2 = -0.5*_p0.second + 0.5*_p2.second;
        a3 = _p1.second;

        p.first  = _p1.first + mu * deltaX;
        p.second = a0 * mu * mu2 +a1 * mu2 + a2 * mu + a3;

        points.push_back( p );
    }

    return points;
}

//----------------------------------------------------------------------------------------------------------

void SCurvedHistogram::updateCurrentPoint(const ::fwRenderQt::data::Event& _event, const ::fwData::Point::sptr& point )
{
    const ::fwData::Histogram::csptr histogram          = this->getInput< ::fwData::Histogram>(s_HISTOGRAM_INPUT);
    const ::fwData::Histogram::fwHistogramValues values = histogram->getValues();

    const float histogramMinValue  = histogram->getMinValue();
    const float histogramBinsWidth = histogram->getBinsWidth();

    // Event coordinates in scene
    const ::fwRenderQt::data::Coord sceneCoord = this->getScene2DRender()->mapToScene( _event.getCoord() );

    const int histIndex = static_cast<int>( sceneCoord.getX() );
    const int index     = static_cast<const int>(histIndex - histogramMinValue);
    const int nbValues  = static_cast<int>(values.size() * histogramBinsWidth);

    if(index >= 0 && index < nbValues && m_positionsToPathLength.find( histIndex ) != m_positionsToPathLength.end())
    {
        const double key     = m_positionsToPathLength[ histIndex ];
        const double percent = m_painterPath->percentAtLength( key );
        const QPointF qPoint = m_painterPath->pointAtPercent( percent );

        point->getCoord()[0] = sceneCoord.getX();
        point->getCoord()[1] = qPoint.y() * static_cast<double>(m_scale);
    }
}

//---------------------------------------------------------------------------------------------------------

SCurvedHistogram::Points SCurvedHistogram::linearInterpolation( const Point _p1, const Point _p2 )
{
    Points points;
    float t = 0.f;
    Point p;
    for(int i = 0; i < 100; ++i)
    {
        t = i / 100;

        p.first  = _p1.first + ( _p2.first - _p1.first ) * static_cast<double>(t);
        p.second = _p1.second + ( _p2.second - _p1.second ) * static_cast<double>(t);
        points.push_back( p );
    }

    return points;
}

//----------------------------------------------------------------------------------------------------------

void SCurvedHistogram::stopping()
{
    if (m_layer)
    {
        this->getScene2DRender()->getScene()->removeItem(m_layer);
        delete m_layer;
        m_layer = nullptr;
    }
    m_positionsToPathLength.clear();
    if (m_painterPath)
    {
        delete m_painterPath;
        m_painterPath = nullptr;
    }
}

//----------------------------------------------------------------------------------------------------------

void SCurvedHistogram::processInteraction( ::fwRenderQt::data::Event& _event)
{
    bool updatePointedPos = false;

    // Vertical scaling
    if( _event.getType() == ::fwRenderQt::data::Event::MouseWheelUp )
    {
        m_scale *= SCALE;
        m_layer->setTransform(QTransform::fromScale(1, static_cast<qreal>(SCALE) ), true);

        updatePointedPos = true;
    }
    else if( _event.getType() == ::fwRenderQt::data::Event::MouseWheelDown )
    {
        m_scale /= SCALE;
        m_layer->setTransform(QTransform::fromScale(1, 1 / static_cast<qreal>(SCALE) ), true);

        updatePointedPos = true;
    }
    else if( _event.getType() == ::fwRenderQt::data::Event::MouseMove )
    {
        updatePointedPos = true;
    }

    ::fwData::Point::sptr point = this->getInOut< ::fwData::Point>( s_POINT_INOUT );
    if( point && updatePointedPos )
    {
        this->updateCurrentPoint( _event, point );
    }
}

//----------------------------------------------------------------------------------------------------------

::fwServices::IService::KeyConnectionsMap SCurvedHistogram::getAutoConnections() const
{
    KeyConnectionsMap connections;
    connections.push( "histogram", ::fwData::Histogram::s_MODIFIED_SIG, s_UPDATE_SLOT );
    return connections;
}

}   // namespace adaptor
}   // namespace scene2D