Qt and game development

[lanz]

QGraphicsView is good for vector graphics with good measure of user interaction, but it getting slow early (around thousand or so objects, but see 40000 chips example http://qt-project.org/doc/qt-4.8/demos-chip.html). It's strength in using qt's painter, that have lots of functionality already implemented (brushes, pens, affine transformations).

OpenGL is OpenGL on every platform, though qt has nice wrapper classes and solid integration with the rest of the framework.

Each way is 100% crossplatform (at least, I haven't bumped into issues).

As for your case, I think QtOpenGL suits it better (though take a look at Qt5/QtQuick, I haven't tried it yet, but they say they extensively use OpenGL and have good perf.)