> Pushing most of the haze shader computation from the vertex to the > fragment level would seem to suggest an approximately constant cost for > the haze for the same view regardless of scenery complexity since the > number of hazy fragments remain about the same.
Thanks for the explanations - that was *really* helpful to understand what is going on. I did a quick check pushing everything which is not vector geometry to the fragment shader, and... * below 20 km visibility range or so, the scheme appears to be a bit (~10 %) slower than it was previously as vertex-based rendering * from about 20 to about 120 km visibility range, I had a constant and quite usable framerate around 22 fps for full screen 1920x1200 resolution (I suppose since this goes per pixel, the screen resolution should affect this). * above 120 km, the vertex part seemed to become an issue again and I went down to 15 fps around 200 km visibility range (this is a lot more than I had previously seen for that range) I guess this confirms your scaling prediction. * best part - for most of the range below 100 km visibility range, maxing out the cloud view range to 75 km didn't make a lot of difference for the framerate (apparently plenty of extra capacity for vertex rendering) In summary: 120 km visibility range with clouds drawn to 75 km at 22 fps with terrain haze and sunset effects on in the F-16 at full screen resolution 1920x1200. There seems to be something going into the right direction here :-) Have to test this more systematically, and also see if I can shuffle stuff from the skydome frag part to vertex. * Thorsten ------------------------------------------------------------------------------ Try before you buy = See our experts in action! The most comprehensive online learning library for Microsoft developers is just $99.99! Visual Studio, SharePoint, SQL - plus HTML5, CSS3, MVC3, Metro Style Apps, more. Free future releases when you subscribe now! http://p.sf.net/sfu/learndevnow-dev2 _______________________________________________ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
