Andy Ross <[EMAIL PROTECTED]> said: > + Being part of the same scene graph as the model, the 3D panels now > "jitter" in exactly the same way. While this makes the jitter of > the attitude gyro less noticeable, it's still *very* noticeable and > annoying. I looked hard for this, and am at this point convinced > that the problem is with the two orientation computations. We have > one in FGLocation that is used by the model code, and one in > FGViewer that is used at the top of the scene graph. My suspicion > is that they don't agree exactly, so the final orientation matrix is > the right answer plus the difference. I did rule out the FDMs > though. None of them show more than about 0.0001 degree of > orientation change between frames for a stopped aircraft. That's > within an order of magnitude of what you'd expect for the > orientation change due to the rotation of the earth (which we don't > model -- I cite it only as evidence of how small this is); far, far > less than one pixel on the screen.
Actually both the model code and the viewer use the FGLocation class, so the data should be the same. The major difference is in the application of the various view offsets which are applied to the FGLocation data in the Viewer and not the model. Note that in cockpit view, the viewer actually accesses the same exact instance of FGLocation that the model uses, so it has to be the same orientation data going in. If there is, as it appears, a variance between the two matrices as they get applied to the view and model, it would have to be attributable to a mathematical error that varies in its effect depending on the specific values involved. Remember the viewer code does apply offsets. Otherwise, it would have to be an issue related to the copying of data that also varies in its effect depending on the specific values. At some point this week I should have time to trace these values and see what is going on. Best, Jim _______________________________________________ Flightgear-devel mailing list [EMAIL PROTECTED] http://mail.flightgear.org/mailman/listinfo/flightgear-devel
