void LineItem::updateChildGeometry(const QRectF &oldParentRect, const QRectF &newParentRect) {
// parent has been resized: update the line's dimensions:
// we would like to have lines in terms of relative endpoint locations,
// but instead they are in terms of length (relative to parent width)
// and angle, relative to the parent.
qreal theta = rotationAngle()*M_PI/180.0;
qreal oldL = relativeWidth()*oldParentRect.width();
// we want to keep the endpoints fixed relative to the parent, so
// we need to calculate new lengths and angles.
qreal newDx = cos(theta)*oldL*newParentRect.width()/oldParentRect.width();
qreal newDy = sin(theta)*oldL*newParentRect.height()/oldParentRect.height();
qreal newWidth = sqrt(newDx*newDx + newDy*newDy);
QTransform transform;
transform.rotate(atan2(newDy, newDx)*180.0/M_PI);
// my brain hurts less for rotations when we center the object at 0,0
QRectF itemRect(-newWidth*0.5, -rect().height()*0.5,
newWidth, rect().height());
// we don't now what the parents's origin is, so, add .x() and .y()
setPos(relativeCenter().x() * newParentRect.width() + newParentRect.x(),
relativeCenter().y() * newParentRect.height()+ newParentRect.y());
setViewRect(itemRect, true);
setTransform(transform);
setRelativeWidth(newWidth / newParentRect.width());
}
void Arrow::paint(QPainter *painter, const QStyleOptionGraphicsItem *option, QWidget *widget)
{
Q_UNUSED(option);
Q_UNUSED(widget);
if (d->points.size() < 2) return ;
// draw the bounding rect if the arrow is selected
if (isSelected() /* && !m_hoverBegin && !m_hoverEnd */) {
painter->save();
painter->setPen(Qt::blue);
painter->drawRect(boundingRect());
painter->restore();
}
if (d->points.isEmpty()) return ;
// prepare pen and brush
painter->save();
QPen pen;
pen.setWidthF(lineWidth()) ;
pen.setCapStyle(Qt::RoundCap) ;
pen.setJoinStyle(Qt::RoundJoin) ;
pen.setColor(getColor()) ;
painter->setPen(pen) ;
QPainterPath path ;
// draw the line
path.moveTo(d->points.first()) ;
if (d->spline && splinePossible(d->points.size()))
{
for (int i = 1 ; i+2 < d->points.size() ; i += 3)
path.cubicTo(d->points[i],
d->points[i+1],
d->points[i+2]);
if (isSelected()) // Draw help lines
{
painter->save();
painter->setPen(Qt::gray) ;
QPointF previous(d->points.first()) ;
for (int i = 1 ; i+2 < d->points.size() ; i += 3)
{
painter->drawLine(previous, d->points[i]) ;
painter->drawLine(d->points[i+1], d->points[i+2]);
previous = d->points[i+2] ;
}
painter->restore();
}
}
else
foreach(const QPointF p, d->points.mid(1))
path.lineTo(p) ;
path.translate(-pos());
painter->drawPath(path) ;
// draw arrow tips
painter->setBrush(pen.color());
qreal tipScaling = relativeWidth();
if (MolScene *sc = qobject_cast<MolScene*>(scene()))
tipScaling *= sc->settings()->arrowTipWidth()->get();
if ((UpperBackward | LowerBackward) & d->arrowType)
painter->drawPath(generateArrowTip(d->points.last(),
d->points[d->points.size()-2],
pos(),
UpperBackward & d->arrowType,
LowerBackward & d->arrowType,
tipScaling
));
if ((UpperForward | LowerForward) & d->arrowType)
painter->drawPath(generateArrowTip(d->points.first(),
d->points[1],
pos(),
LowerForward & d->arrowType,
UpperForward & d->arrowType,
tipScaling
)) ;
painter->restore();
graphicsItem::paint(painter, option, widget);
}
