On 12/12/2011 8:37 AM, Ethan Fahy wrote: > Object rotation is the last piece of this puzzle. When on object is placed > on a geocentric terrain using the methods outlined in this thread, the object > always appears to be oriented correctly upwards with respect to the center of > the earth. However I'm not sure how it is being oriented with respect to its > rotation. Does anyone have any insight into this? For example if I know > that my object's internal coordinate system specifies that positive x is > north and positive y is west and I place that object on an arbitrary WGS84, > geocentric terrain, how will I know how to rotate the object to line up the > north orientation?
Just try it. Make an object that points out the X Y and Z local axes graphically and stick it in using the EllispoidModel to orient it to the local ground's upvector and such. It will show you what the orientation ended up like, and then you can see what additional rotations might be needed to get what you expect. I can't recall off the top of my head which object local axis ends up pointed north. -- Chris 'Xenon' Hanson, omo sanza lettere. [email protected] http://www.alphapixel.com/ Digital Imaging. OpenGL. Scene Graphs. GIS. GPS. Training. Consulting. Contracting. "There is no Truth. There is only Perception. To Perceive is to Exist." - Xen _______________________________________________ osg-users mailing list [email protected] http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
