QWMatrix::mapRect

Hello all,

I am fighting with a problem regarding mapping a rectangle which is not of

QRect type. I want to rotate the rectangle 90 degree counterclockwise and

I just did it as follow but the result is not what I want.Instead the rectangle

gets larger in size. Can someone give me suggestions how to solve this problem?

Code:

---

QWMatrix matrixWorld;
	 QRect newRect;
	 double rotateDegree = 90.0;
 
	 newRect.setRect(myRect.Left(), myRect.Top(), myRect.Width(), myRect.Height()); 
	 matrixWorld.rotate(rotateDegree);
	 newRect =  matrixWorld.mapRect(newRect);
	 myRect.Rect(newRect.left(), newRect.top(), newRect.width(), newRect.height());

---

What is QWMatrix ???

The QWMatrix class specifies 2D transformations of a coordinate system.
The standard coordinate system of a paint device has the origin located at the top-left position. X values increase to the right; Y values increase downward.

Anyone knows how to solve this problem?? :confused:

in Qt I found only QMatrix and there are some small examples with rotation. the interafe of this class very similar to class which you was describe.

You can do the 90 degrees rotation without any matrices. Just swap coordinates and multiply one of them by -1.