Take the 2-minute tour ×  I am fairly new to Qt and have been
doing a lot of reading and practicing exercises. I have searched
for this one quite a lot but I could not find any examples.  I
have a QPixmap object to which I load a .png image. I need to
create a copy of this QPixmap with a dark mask applied to it.
Basically I want this QPixmap's image to be covered with a layer
of solid black of which the opacity is set to 50%.  I know how
to set the opacity of a QPixmap's image but how can I add a
layer of solid black with opacity on it?  Thank you!
share|improve this question add comment  1 Answer  up vote 2
down vote accepted  You can use a QPainter and you a semi-
transparent QBrush to paint that dark layer onto your QPixmap.
Assuming pic is a QPixmap loaded with your image:  QPainter
p(&pic); QBrush b(QColor(0,0,0,128)); // adjust color and alpha
to taste p.drawRect(0, 0, 200, 200);  Effect (before/after):
enter image description here    vs    enter image description
here  The opaque black border can be