David Megginson writes: > Marcio Shimoda writes: > > > What function draws the sky and the tile? > > The sky is drawn in SimGear -- see simgear/sky/dome.cxx. It's not > integrated with the SSG graph, and that may or may not be part of the > problem.
The scene drawing is split into several phases: Step 1: the sky dome, the sun, moon, stars, planets. This forms the back drop. Everything else is drawn in front of these sky items. Step 2: draw the terrain. This needs to go in front of sky back drop so it is drawn next. Step 3: draw the clouds. The clouds have alpha so they are drawn last. However, if the tree has been already drawn, then the sky won't show throw because the depth buffering of the tree polygons masks it out. Everything with alpha really needs to be thrown in a big bin and all drawn back to front in one step. However, with things like the clouds that are "huge" relative everything else, how do you calculate the distance of the cloud layer? Probably to the nearest point is what we want, but I doubt that is what plib uses ... it probably goes off the 'reference' point or center of the bounding sphere of each partially transparent leaf node. This is a problem ... this might be a good one to ask on the plib list to see if they can provide suggestions? Curt. -- Curtis Olson IVLab / HumanFIRST Program FlightGear Project Twin Cities [EMAIL PROTECTED] [EMAIL PROTECTED] Minnesota http://www.menet.umn.edu/~curt http://www.flightgear.org _______________________________________________ Flightgear-devel mailing list [EMAIL PROTECTED] http://mail.flightgear.org/mailman/listinfo/flightgear-devel
