This what you see when you check the Post-FX checkbox.
THIS IS NOT A BUG!
It’s only the post processing effect that draws some random bands. What’s more, the post processing effect does not cover the whole screen (may be that makes things worse…).
Post processing allows to add visual effects to the final scene (by increasing realism with depth of field post-FX or by adding a touch of fun with other kind of NPR post-FX like this one). And according to what I read over the web, a lot of people think they have a problem with their system 😀
Maybe this post-fx is too real….
Okay, for the next update of FluidMark, I will replace this post-fx by a more conventional one like a bloom effect.
And for all pixel hackers, the post-fx source code is in the post-fx.xml file in FluidMark folder.