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using Anti-Aliasing makes my aim-circle looking slightly wrong.
I'm using a gui-image for that.
Maybe Anti-Aliasing should not modify gui-images, cause these are
correct as they are in most cases.
It's planned to make GUI anti-aliasing switchable in Irrlicht 1.6. Irrlicht 1.5.1 will probably disable it. In case the driver overrides the anti-aliasing setting we cannot change a thing, though.