turtle wrote in Sun Mar 27, 2016 8:20 pm:I have a R9 Fury (Strix Edition) which I consider should be able to run FlightGear with all the eye-candy just fine. However, when I launch the simulator I am getting 20-25 FPS in it's default configuration. I went ahead and turned off Rembrandt, and now I am seeing 50-60 FPS.
I'm curious to know if this is an AMD or Nvidia issue, or just Rembrandt being tough to run in general?
I might be getting a new graphics card this year, so I want to know what I will be losing with FlightGear before I buy.
Rembrandt is harder work for both the GPU and the CPU, and this goes up exponentially with the amount of geometry. However on my R9-290 the
report that Hooray referenced shows that vsync is making this worse. This could just be the drivers on my system, or an OpenGL / OSG strangeness. The basic problem is that OSG is waiting for a vsync for each camera, which hits rembrandt hard as it has a lot of cameras.
However you will get faster frame rates, better lighting, cloud shadows, trees that move in the wind and a whole heap more features using Atmospheric Light Scattering (ALS) rather than Rembrandt.
Rembrandt (deferred rendering) really is about emissive lights, the ability to do shadows within deferred rendering is more suited to much smaller fields of views. The shadows usually flicker around the edges in a cockpit view (less noticably externally).
At the moment I'd say that ALS is the way to get the best looking visuals. ALS works best with detailed weather (aka. advanced or local weather). There are some extra shader settings on the configuration for detailed weather.
There are other problems with AMD graphics cards (I can't use point lighting and often the text in dialogs / menus flickers). This is probably a driver problem.
I'd generally recommend nVidia kit for FlightGear simply because most of the develoment team use it.