At 4/12/02, you wrote: >Can we check the bounding sphere of the model and, if the viewpoint is >outside it, use the nearest point of the sphere as a candidate for the >clip plane ? Doesn't help for pilot viewpoint, but should for trailing.
I don't know if this is related. I have a R/C glider model that has an 8 ft wingspan. When viewed externally, I found that when I moved the viewpoint close to the model, parts of the model would vanish. When this happened, the model was still pretty far away. So what I did instead was to move out to a point where the model was not clipped and then zoom in. This is not ideal because it also magnifies the scenery in the background. If this clipping problem is related to what Alex mentions above, then his proposed solution would solve the problem for small aircraft as well. > > David Megginson <[EMAIL PROTECTED]> said: > > > > > Curtis L. Olson writes: > > > > > > > Could the interior be marked as a separate branch of the scene graph > > > > and then somehow skipped when viewed from an external view? > > > > > > We wouldn't want to do that in general -- it would be OK for the 3D > > > instruments and controls, but if we killed the cockpit interior walls, > > > you'd see nothing but sky through the plane windows (i.e. the other > > > side would look like it was missing). That's not a problem if you're > > > far enough away, of course. > > > > > The real problem is that the current CVS is using a different clip > > > plane for the 3D model even in external view. Jim's patch is supposed > > > to fix that, but I haven't had a chance to test it yet. > > > > Actually I'm still seeing some pretty bad problems even with that > patch. The > > patch just puts it back to the functionality we had before which seemed a > > little better. Something is still missing though (from before moving the > > model rendering stuff). As Erik noted there's some really weird alpha > channel > > stuff happening to the model. > > > > What I mentioned before was something "academic" (ie maybe read about it in > > the opengl book?). Basically opengl offers a method that uses vertex > order to > > select out inner facing polygons and yes you'd see clear sky, but it would > > only be applied at a certain distance so that wouldn't be much of a > problem. > > I'm guessing that the same thing could be accomplished with the scenegraph > > method if the interior walls, floor and ceiling were seperate polys and the > > outside shell was singlesided. All we would need is to have a distance > from > > eyepoint to origin to decide whether to include the branch. > > > > Best, > > > > Jim > > > > _______________________________________________ > > Flightgear-devel mailing list > > [EMAIL PROTECTED] > > http://mail.flightgear.org/mailman/listinfo/flightgear-devel > > > > > >_______________________________________________ >Flightgear-devel mailing list >[EMAIL PROTECTED] >http://mail.flightgear.org/mailman/listinfo/flightgear-devel ************************************************** Prof. Michael S. Selig Dept. of Aero/Astro Engineering University of Illinois at Urbana-Champaign 306 Talbot Laboratory 104 South Wright Street Urbana, IL 61801-2935 (217) 244-5757 (o), (509) 691-1373 (fax) mailto:[EMAIL PROTECTED] http://www.uiuc.edu/ph/www/m-selig http://www.uiuc.edu/ph/www/m-selig/faq.html (FAQ) ************************************************** _______________________________________________ Flightgear-devel mailing list [EMAIL PROTECTED] http://mail.flightgear.org/mailman/listinfo/flightgear-devel
