Hi Torben, On Mon, Jul 18, 2011 at 12:20 PM, Torben Dannhauer <[email protected]> wrote: > About the changes: I agree, the documentation should be improved... I did not > document the callback because I only untderstand the basic idea - currently > I'm not familiar with the pager topic.
Comment attached to the email I just posted... > Regarding the height of terrain calculation: > I think it is calculated the other way around: > The calculated intersection point represents the height of terrain. > The height above terrain is calculated by the distance from the passed test > point to the intersection point aka height of terrain. > Therefore the additional computation is only the calculation of the height in > case of an existing ellipsoid model. > > In my optionen it is better to store the calculated hot to be directly usable > instead of calculating hot via calculating hat which is internally calculated > via hot. > > I don't know how oftern other developers use hot, but in my case hot is even > more important than hat because I use it to place objects correctly on the > ground. Your use of the abreviation HOT is the first I've come across, HAT is used all the time though, so I would suspect that Height Of Terrain is used less. HAT is used for terrain following/basic collision test. For placing objects on the ground one would typically use a straight intersection tests and get back the actual intersection point and the parental path. I don't think it makes much sense to try and reuse the HAT class for this, as you are doing lots of computations totally unnecessary - the IntersectionVisitor/LineSegmentIntersector provide all the required information for you. > Often I read in the forum questions regarding hat/hot, so my primary goal is > to provide an easy to use class for hat and hot, with and without pagin in > the highest LOD. The point of the HeightAboveTerrain class is to provide a easy to use class that supports paging in of the tiles. The base osgUtil::IntersectionVsitor/LineSegmentInterector is actually what is used under the hood and is more flexible and powerful - just slightly more involved to use. > P.S.: I hope you had some recreative days with your family :) Thanks, we had a good two weeks away. I'm now back to work, but not quite full time as my wife and I are juggling child care with work since our three children are now all off school for the summer and we both have jobs.... So I'm trying to catch up with submissions and client work, but generally keeping a low profile. Robert. _______________________________________________ osg-submissions mailing list [email protected] http://lists.openscenegraph.org/listinfo.cgi/osg-submissions-openscenegraph.org
