Am Sonntag 30 März 2008 schrieb BARANGER Emmanuel: > Hi all, > > After some tries on the Paris scenery and with nels' help on jabber, > here are a few screenshots showing how much a textured ground > dramatically improves Flightgear rendering. > > http://helijah.free.fr/ground/JPG-Version/ > > Well, for now the method is just eavy as we have to make use of > materials.xml. But still, isn't this a convaincing result ?
While this might seem superior on first glance, I see many issues with that simple approach, some of them noticeable even in your screenshots: * Using aerial photography on a worldwide scale means creating a second google earth, with all related demands as to storage space. Not to mention copyright issues/free data sources. * Usually the pictures contain shadows that naturally don't align with the sim state most of the time. Even worse the shadow code of FG might create doubled shadows in opposite directions. * Any misplaced buildings spring to eye immediately as there is a ghost groundplan visible some distance away (see the Orly shots). * All aerial photos that are not orthorectified contain distortions (depending on altitude and lateral distance of the shooting aircraft), that might be impossible to cover by a 3d building even if placed correctly. This is especially true for high rises and skyscrapers. * In the densely populated areas of Paris note the mismatch between the 3d buildings and the streets. This is not specific to aerial photos but more pronounced, as more streets are directly visible. * As it looks nice in still images at a certain altitude, I suppose much of the effect is lost in a live session, as depth perception is improved with motion. In Paris this degradation is probably covered by the hundreds of 3d buildings which aren't available elsewhere (yet). That said, I don't think your approach is meaningless. Given that the project area is small and built up areas are covered with 3d buildings it provides a more detailed and more accurate view of the project area than the standard approach. Depending on the projects goals this might be what you want, as also Curt has shown in his synthetic view video. So having kind of a tutorial or howto seems to be a good idea, so that others might reproduce what you've done in Paris. Thomas ------------------------------------------------------------------------- Check out the new SourceForge.net Marketplace. It's the best place to buy or sell services for just about anything Open Source. http://ad.doubleclick.net/clk;164216239;13503038;w?http://sf.net/marketplace _______________________________________________ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
