QPixmap, PNG and Transparency

[jsmax]

Hi. I have a QPixmap object loaded from a PNG file with transparency. This pixmap is displayed onto a QGraphicsScene via an overloaded QGraphicsItem.

I want the item to be more "lighty" when it is selected. I'm doing something like this:

painter->fillRect(boundingRect(), Qt::gray);
painter->setCompositionMode(QPainter::CompositionMode_Overlay);
QRect rect = boundingRect().toRect();
painter->drawPixmap(rect, myPixmap);

painter->fillRect(boundingRect(), Qt::gray);
painter->setCompositionMode(QPainter::CompositionMode_Overlay);
QRect rect = boundingRect().toRect();
painter->drawPixmap(rect, myPixmap);

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It's working, but the problem is that the transparent region of the pixmap becomes "grayed" too ...

How can i draw the gray color just on the real icon, not touching the transparent region of the pixmap ?

[high_flyer]

some ideas that come to mind:
a. you can have a look at the effect classes see if you find something there
b. you can have a light and dark version of your image in two pixmaps
c. you can set a mask to your pixmap if its not changing size.

[jsmax]

The first idea is what i wanted. Now using the QGraphicsOpacityEffect class.

Thanks a lot