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QList<QGraphicsLineItem*>   *   fhorizontalLines;
QList<QGraphicsLineItem*>   *   fverticalLines;

void            QEditorScene::removeGrid()
{
    QGraphicsLineItem * item;

    for(QList<QGraphicsLineItem*>::iterator it = fhorizontalLines->begin(); it!= fhorizontalLines->end(); it++)
    {
        item = *it;
        this->removeItem(item);
        delete item;
    }

    for(QList<QGraphicsLineItem*>::iterator it = fverticalLines->begin(); it!= fverticalLines->end(); it++)
    {
        item = *it;
        this->removeItem(item);
        delete item;
    }

    fhorizontalLines->clear();
    fverticalLines->clear();
}

void            QEditorScene::createGrid(int xmax, int x_step, int ymax, int y_step)
{
    QPen pen;

    QColor  gridColor = Qt::white;
    gridColor.setAlpha(100);
    pen.setColor(gridColor);
    pen.setWidthF(0.25);

    int xoffset = xmax / x_step;

    for(int i=0;i<xmax;i+=xoffset)
    {
        QGraphicsLineItem * item = this->addLine(i,0,i,ymax,pen);
        item->setFlags(QGraphicsItem::ItemStacksBehindParent);
        item->setZValue(-3000);
        fverticalLines->push_back(item);
    }

    int yoffset = ymax / y_step;

    for(int i=0;i<ymax;i+=yoffset)
    {
        QGraphicsLineItem * item = this->addLine(0,i,xmax,i,pen);
        item->setFlags(QGraphicsItem::ItemStacksBehindParent);
        item->setZValue(-3000);
        fverticalLines->push_back(item);
    }

    int offset = yoffset/2;

    gridColor = Qt::magenta;
    gridColor.setAlpha(150);
    pen.setColor(gridColor);
    pen.setWidthF(0.25);

    for(int i=offset;i<(ymax-offset);i+=yoffset)
    {
        QGraphicsLineItem * item = this->addLine(0,i,xmax,i,pen);
        item->setFlags(QGraphicsItem::ItemStacksBehindParent);
        item->setZValue(-3000);
        fverticalLines->push_back(item);
    }
}