RE: [Flightgear-devel] YASIM bug/feature (was Stopped making dc3-cockpit, need help)
Vivian Meazza wrote Ilja Moderau wrote: I was using the AC3d version 3.6. Screenshot: http://mitglied.lycos.de/iljamod/throttle.jpg There is the file: http://mitglied.lycos.de/iljamod/dc3-throttle.zip Sorry to hear that you haven't been able to make 3D instruments work for the DC3 model. Have you been trying to use AC3D Ver 4? It doesn't work without some work around for the crease token. If you would like to send me an example of what isn't working off-list, I'll try to figure out why. 3D instruments are definitely possible. I think the problem is your naming of objects - I removed the decimal points - and it works Whilst working on the DC3 model, trying to help a little with this problem, I noted that the model flies left-wing low. This seems to be related to the twist element set on the wing. The DC3 has -3 deg set. Reverse this and the model flies wings right wing low. It seems as if the twist applies across the whole wing rather than being reversed for half the wing. It won't run at all with twist = 0. Is this a bug or a feature? See http://myweb.tiscali.co.uk/vmeazza/FlightGear/fgfs-screen-010.jpg http://myweb.tiscali.co.uk/vmeazza/FlightGear/fgfs-screen-011.jpg Both snapshots were taken with the wing leveller (Ctrl W) engaged Regards Vivian Meazza ___ Flightgear-devel mailing list [EMAIL PROTECTED] http://mail.flightgear.org/mailman/listinfo/flightgear-devel
Re: [Flightgear-devel] YASIM bug/feature (was Stopped making dc3-cockpit, need help)
Vivian Meazza wrote: Whilst working on the DC3 model, trying to help a little with this problem, I noted that the model flies left-wing low. This seems to be related to the twist element set on the wing. The DC3 has -3 deg set. Reverse this and the model flies wings right wing low. It seems as if the twist applies across the whole wing rather than being reversed for half the wing. It won't run at all with twist = 0. Is this a bug or a feature? Indeed, the twist assignment for wings looks a little wrong. These are the twist assignments for the symmetrical left and right wing segments: s-setTwist(_twist * frac); s-setTwist(_twist * Math::sqrt(frac)); This is almost certainly a mistake; I took the sqrt() call out and committed a symmetric right-side twist to CVS. David, this was your code originally, right? Is that your intent, or should I have put a sqrt() into the left side? Andy Index: Wing.cpp === RCS file: /var/cvs/FlightGear-0.9/source/src/FDM/YASim/Wing.cpp,v retrieving revision 1.4 diff -u -r1.4 Wing.cpp --- Wing.cpp18 Feb 2003 17:37:28 - 1.4 +++ Wing.cpp9 Feb 2004 15:11:32 - @@ -360,7 +360,7 @@ sr-surface = s; sr-weight = chord * segWid; s-setTotalDrag(sr-weight); -s-setTwist(_twist * Math::sqrt(frac)); +s-setTwist(_twist * frac); _surfs.add(sr); } } ___ Flightgear-devel mailing list [EMAIL PROTECTED] http://mail.flightgear.org/mailman/listinfo/flightgear-devel
Re: [Flightgear-devel] YASIM bug/feature (was Stopped making dc3-cockpit, need help)
Andy Ross wrote: Indeed, the twist assignment for wings looks a little wrong. These are the twist assignments for the symmetrical left and right wing segments: s-setTwist(_twist * frac); s-setTwist(_twist * Math::sqrt(frac)); It looks like I screwed it up between versions 1.3 and 1.4; in 1.3, I had s-setTwist(_twist * Math::sqrt(1-frac)) s-setTwist(_twist * Math::sqrt(frac)) I don't know exactly what I was trying to accomplish with this, except perhaps to make sure that the twists were mirror images of each other. All the best, David ___ Flightgear-devel mailing list [EMAIL PROTECTED] http://mail.flightgear.org/mailman/listinfo/flightgear-devel
Re: [Flightgear-devel] YASIM bug/feature (was Stopped making dc3-cockpit, need help)
David Megginson wrote: It looks like I screwed it up between versions 1.3 and 1.4; in 1.3, I had s-setTwist(_twist * Math::sqrt(1-frac)) s-setTwist(_twist * Math::sqrt(frac)) I don't know exactly what I was trying to accomplish with this, except perhaps to make sure that the twists were mirror images of each other. They shouldn't need special handling. The way the orientation matrices are set up, the incidence angle is treated the same way (i.e. positive == higher AoA) for both sides. I'll change both to sqrt(frac) terms then, since this matches your original code better. Andy ___ Flightgear-devel mailing list [EMAIL PROTECTED] http://mail.flightgear.org/mailman/listinfo/flightgear-devel
