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#include "line.h"
#include "qglbuilder.h"

QT_BEGIN_NAMESPACE

/*!
    \qmltype Line
    \instantiates Line
    \brief The Line item represents a geometric line drawn in 3D space.
    \since 4.8
    \ingroup qt3d::qml3d::shapes
    \inherits Item3D

    The Line element in QML provides a means of drawing lines in a 3D
    environment.  For example, the following QML code draws a line between
    point (0,0,0), (1,1,1), then to (-1,-1,-1).

    \code

    Line {
        vertices: [
           0, 0, 0,
           0, 0, 1,
           0, 1, 1

        ]
        effect: Effect {
            color: "#aaca00"
        }
    }
    \endcode

    The Line element is part of the \c{Qt3D.Shapes} namespace,
    so the following must appear at the top of any QML file that
    references it:

    \code
    import Qt3D.Shapes 2.0
    \endcode

    \sa Item3D
*/
/*!
    \internal
*/
Line::Line(QObject *parent) :
    QQuickItem3D(parent)
    ,m_width(3.0)
    ,m_geometry(0)
    ,m_changeFlag(false)
{
    //meh
}

Line::~Line()
{
    delete m_geometry;
}

/*!
   \qmlproperty list<real> Line::vertices

   This property defines the positions for all of the vertices in the
   line strip.  Each vertex is given by three real values, defining
   the x, y, and z co-ordinates of the vertex.
*/

QVariant Line::vertices() const
{
   return m_vertices;
}

void Line::setVertices(const QVariant &value)
{
    m_vertices = value;

    //Update the actual QVector3DArray containing the line points.
    m_vertexArray.clear();
    QVariantList vertlist = m_vertices.toList();
    for (int index = 0; (index + 2) < vertlist.size(); index += 3) {
        m_vertexArray.append(vertlist.at(index).toFloat(), vertlist.at(index + 1).toFloat(), vertlist.at(index + 2).toFloat());
    }
    m_changeFlag=true;
    emit verticesChanged();
    update();
}


/*!
    \qmlproperty real Line::width

    This property defines the width of the line.  The
    default is 1.0
*/
void Line::setWidth(float width)
{
    if (m_width != width) {
        m_width = width;
        m_changeFlag=true;
        emit widthChanged();
        update();
    }
}

/*!
    \internal
*/
void Line::drawItem(QGLPainter *painter)
{
    if (m_changeFlag || !m_geometry) {
        if (m_geometry) delete m_geometry;

        QGLBuilder builder;

        QGeometryData lineCollection;
        builder.newSection();

        lineCollection.appendVertexArray(m_vertexArray);

        builder.addTriangles(lineCollection);
        builder.currentNode()->setDrawingMode(QGL::LineStrip);
        builder.currentNode()->setDrawingWidth(m_width);
        m_geometry = builder.finalizedSceneNode();

        m_changeFlag = false;
    }

    // Draw the geometry.
    m_geometry->draw(painter);
}

QT_END_NAMESPACE

