> > > 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. > > FWIW, I saw with gDebugger that the sky dome is made of more than > 23000 vertices, even if a small amount of them are really displayed on > screen. > > In Rembrandt, several pass are done on 1/16th of the size of the > screen (1/4th of each dimension), relying on the mag filter to cover the > whole screen. This is the case of the blur pass in the AO or Bloom effects.
BTW, in my other terrain engine project, the sky is drawn with a quad (4 vertices at the corners of the screen). The view direction is computed in the vertex shader and then interpolated in a varying and renormalized in the fragment shader. That way there is no wasted computation (except the region overdrawn by the terrain, but that could be optimized with a stencil buffer) -Fred ------------------------------------------------------------------------------ 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
