On Tuesday 20 July 2004 15:52, Jim Wilson wrote: > "Ampere K. Hardraade" said: > > On July 8, 2004 09:47 am, Andy Ross wrote: > > > Not to pass the buck, but this is really a plib question. > > > > Why did I have a feeling that I was going to get that answer? =P > > > > In the short term, I guess I can export those parts that need > > illumination into ac format, thus bypassing the whole 3ds illumination > > problem altogether. However, I don't think this can be a permanent > > solution. As far as I can tell, illumination in ac format seems to be an > > all or nothing deal -- either the entire object illuminates, or no > > illumination at all. If my observation is correct, this means that it > > won't be possible to create effects such as lighting fall off. So in the > > long term, it will probably be a good idea to sort out the effects > > (illumination, glossness, specular level, transparency, perhaps > > reflection, etc.) within FlightGear before passing things to plib for > > rendering (without breaking the encapsulation of course). > > I'm not sure what you are saying here. It is certainly possible to have > emissivity values set at intermediate levels, and to have them specified > per vertex (actually per surface). > > There currently isn't any support for fading (dynamically changing) > emissive properties in our animation code, but it probably could be done. > Actually it is on my list of things to investigate "when I get a few extra > minutes" (tm) as it would be great for the modeling of 3D cockpit/panel > lighting. > > Best, > > Jim
Hello Jim, actually, I think there is an animation method (blend) that allows texture fading. I did some experiments with adapting the shadow-map idea to simulate landing lights and in principle it seemed to work ok. Fwiw, it involved animating a rectangle textured with a white emissive transparent landing-light shaped texture onto the ground ahead of the a/c and at night it actually lightened the ground when seen through the texture. Along with fading the texture in or out, with decreasing or increasing agl to vary the apparent brightness, the rectangle was also scaled (scale) to get bigger or smaller, again varying on agl. I've pasted those two animation sections below, if you want an example. <!-- Fade out --> <animation> <type>blend</type> <object-name>LLightsMap</object-name> <property>/position/altitude-agl-ft</property> <factor>0.003</factor> <min>0.0</min> </animation> <!-- Scale with Altitude --> <animation> <type>scale</type> <object-name>LLightsMap</object-name> <property>/position/altitude-agl-ft</property> <x-factor>0.05</x-factor> <x-offset>1.0</x-offset> <y-factor>0.05</y-factor> <y-offset>1.0</y-offset> <z-factor>0.0</z-factor> <z-offset>1.0</z-offset> </animation> (Heh! - these were from the latest version of the testing I could find so I think these examples actually worked) LeeE _______________________________________________ Flightgear-devel mailing list [EMAIL PROTECTED] http://mail.flightgear.org/mailman/listinfo/flightgear-devel
