Understanding QPainterPath::simplified()

Hello.
My implementation of 'paintEvent' is giving a particular result:

Code:

---

void Widget::paintEvent( QPaintEvent * event )
{
	QPainter p ( this );
	p.setPen( QPen( QBrush( Qt::darkRed ), 2 ) );
	p.setBrush( QBrush( Qt::gray ) );
 
	QPainterPath myPath;
	myPath.moveTo( 600.0, 250.0 );
	myPath.cubicTo( 90.0, 50.0, 0.0, 50.0, 50.0, 370.0 );
	myPath.cubicTo( 140.0, 20.0, 10.0, 10.0, 600.0, 250.0 );
 
	myPath.addRect( 10.0, 300.0, 160.0, 34.0 );
 
	QPainterPath result ( myPath.simplified() );
	p.drawPath( result );
}

---

Looking like this:
http://s7.postimg.org/3s67tyfwb/painter_Path.png

Shouldn't the intersected region between the rectangle and the bezier path be filled in the path generated by the 'simplified' call?

What fill mode do you have set on the path?

Hello.
I'm using WindingFill, but in any case I tested with either of the fill modes and the result is the same.

According to some more research, QPainterPath::simplified will output a path that looks the same as the original when painted.
So for "moveTo" elements like that rectangle I can create a temporary path and then unite both as a boolean operation.
Additionally, QPainterPath::simplified will convert that path which originally has 7 elements into a 145 "lineTo" elements path that is an approximation, so it won't work for what I want.

This is the result from QPainterPath::simplified:
http://s15.postimg.org/gp8t6acnv/painter_Path2.png

I'll try something with a computational geometry library, and then feed the results back to Qt for rendering.