What kind of performance gains will we see from this?
According to documentation this allows us use hardware rendering for drawing a scene. Of course not in all cases this will increase performance, your system must support hardware acceleration for you to see any boost.
Right now rendering a scene is not our the most biggest problem, we spend most time on parsing and calculating. But if we can pass some calculation to GPU we can have benefit from it. Of course this is all theoretical i don't have proofs, i even don't have video card in my PC. This is the main reason why this mode will be disabled by default.
I personally think this is very interesting. I run a powerful graphics card, and I know from experience that for example Adobe Illustrator sees much improved performance when in OpenGL mode.
The patch is very easy and is almost ready. Next test build will have this change.