How can I do something like QGraphicsItem::setShear?

[wayfaerer]

I'm trying to shear a QGraphicsItem with a custom transformOriginPoint, but there is no QGraphicsItem::setShear (like there is for rotation: QGraphicsItem::setRotation).

I realize I could create my own transform matrix and use QGraphicsItem::setTransform, but it doesn't seem to take into account the transformOriginPoint, which in my case is not (0,0).

For example, the following two examples produce completely different behavior:

// takes into account the transformOriginPoint
myItem->setRotation(30);

// takes into account the transformOriginPoint
myItem->setRotation(30);

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// does not take into account the transformOriginPoint
QTransform hi;
hi.rotate(30);
myItem->setTransform(hi);

// does not take into account the transformOriginPoint
QTransform hi;
hi.rotate(30);
myItem->setTransform(hi);

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[wayfaerer]

I must be missing something. There's no setShear function in the docs or in the normal QGraphicsItem source file, yet there is in this version of QGraphicsItem:

http://qt.gitorious.org/qt/qt/blobs/...aphicsitem.cpp

[wysota]

setOriginPoint is equal to translating the transform before doing other transformations and then at the end translating it back.