No description
4c10ef139c
I have done a patch to eliminate the jitter of 3D-objects near the viewpoint (for example 3D cockpit objects). The problem is the roundoff accuracy of the float values used in the scenegraph together with the transforms of the eyepoint relative to the scenery center. The solution will be to move the scenery center near the view point. This way floats relative accuracy is enough to show a stable picture. To get that right I have introduced a transform node for the scenegraph which is responsible for that shift and uses double values as long as possible. The scenery subsystem now has a list of all those transforms required to place objects in the world and will tell all those transforms that the scenery center has changed when the set_scenery_center() of the scenery subsystem is called. The problem was not solvable by SGModelPlacement and SGLocation, since not all objects, especially the scenery, are placed using these classes. The first approach was to have the scenery center exactly at the eyepoint. This works well for the cockpit. But then the ground jitters a bit below the aircraft. With our default views you can't see that, but that F-18 has a camera view below the left engine intake with the nose gear and the ground in its field of view, here I could see that. Having the scenery center constant will still have this roundoff problems, but like it is now too, the roundoff error here is exactly the same in each frame, so you will not notice any jitter. The real solution is now to keep the scenery center constant as long as it is in a ball of 30m radius around the view point. If the scenery center is outside this ball, just put it at the view point. As a sideeffect of now beeing able to switch the scenery center in the whole scenegraph with one function call, I was able to remove a one half of a problem when switching views, where the scenery center was far off for one or two frames past switching from one view to the next. Also included is a fix to the other half of this problem, where the view position was not yet copied into a view when it is switched (at least under glut). This was responsible for the 'Error: ...' messages of the cloud subsystem when views were switched. |
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| docs-mini | ||
| examples/netfdm | ||
| man | ||
| package | ||
| scripts | ||
| src | ||
| tests | ||
| utils | ||
| .cvsignore | ||
| acinclude.m4 | ||
| am2dsp.cfg | ||
| AUTHORS | ||
| autogen.sh | ||
| ChangeLog | ||
| configure.ac | ||
| FlightGear.dsp | ||
| FlightGear.dsw | ||
| Makefile.am | ||
| NEWS | ||
| README | ||
| Thanks | ||
Welcome to the FlightGear Flight Simulator project. =================================================== The primary web page for this project is: http://www.flightgear.org For basic installation instructions see the "INSTALL" file. Before you can run FlightGear you will also need to download and install the "base" package which is a collection of textures, sounds, sample scenery, and other data files need by the sim. For additional install help for specific platforms please browse the "docs-mini/" subdirectory. More complete documentation is available from our web page as a separate distribution. Please take a look at the "Thanks" file for a list of people who have contributed to this project. If you have contributed something but don't find your name in this file. Please send a polite reminder to http://www.flightgear.org/~curt For a summary of changes/additions by version see the "NEWS" file. This project is GPL'd. For complete details on our licensing please see the "COPYING" file. For information on available mailing lists, mailing list archives, and other available source code and documenation, please visit our web site. FlightGear is a product of the collaboration of large international group of volunteers. FlightGear is a work in progress. FlightGear comes with no warrantee. We hope you enjoy FlightGear and/or find it of some value!