Thanks for keeping me on my toes, Gordon. :-)
Hmm... I just went back and re-read the FLT spec section regarding LOD
Records. Throughout the description, the spec refers to "distance"
calculations and switch in/out "distances", implying strongly that distance
is the only way to change active LODs. Finally, the section ends with the
following (arguably cryptic) text:
"Significant size is a value used to calculate switch in and out
distances based on viewing parameters of your simulation display system.
This value is used internally by MultiGen-Paradigm and will be enhanced in
future versions of OpenFlight."
So this is just for internal use. We can hijack this field if we want, but
it's vague enough ("based on viewing parameters of your simulation display
system") that, if ever exposed for public use, this field could be used for
just about anything.
I'm not trying to get out of doing work, and it would be trivial to map
OSG's pixel size on screen to this field. But the 16.1 spec language doesn't
convince me that this is the right thing to do. If I'm way off base, please
correct me...
-Paul
>
> Hi Paul
>
> Err Creator/Openflight does support this ;) it's called
> 'Significant Size', which is a single value. On the Open
> Flight LOD node
>
> Obviously it up to the scene graph what field means ;), the
> OSG flight loader may not support this ( not checked ), so to
> support it Changes may need to be made to the read and write
>
> __________________________________________________________
> Gordon Tomlinson
>
> Email : [EMAIL PROTECTED]
> YIM/AIM : gordon3dBrit
> MSN IM : [EMAIL PROTECTED]
> Website : www.vis-sim.com www.gordontomlinson.com
> __________________________________________________________
>
> -----Original Message-----
> From: [EMAIL PROTECTED]
> [mailto:[EMAIL PROTECTED] On Behalf
> Of Paul Martz
> Sent: Monday, June 16, 2008 11:04 PM
> To: [EMAIL PROTECTED]; 'OpenSceneGraph Users'
> Subject: Re: [osg-users] OpenFlight exporter question
>
> Hi Brian -- Your LOD node is configured to switch children
> based on screen size. OpenFlight doesn't support this. You'll
> need to re-model the LODs using eye distance.
>
> The LOD exporter should probably display a warning in this
> case, but as I am in the middle of a vacation, I won't be
> able to make that change immediately. Could you please add
> the warning message and post to osg-submissions? Thanks.
> -Paul
>
> >
> > Hi Paul,
> >
> > Yes, I thought about the version possibly being an issue, so I
> > downloaded 2.5.2 but saw the same problem.
> >
> > Back a few months ago, I was given a sample LOD OSG file.
> As a test I
> > ran the converter against it, but it also had the same
> problem. I've
> > attached the file that Hans Elbers provided me and am curious as to
> > whether its format is correct in terms of the converter. Are there
> > any command line switches that I need to use with osgconv?
> >
> > Thanks,
> > Brian
> >
> > On Mon Jun 16 12:43 , 'Paul Martz' <[EMAIL PROTECTED]> sent:
> >
> > >Hi Brian -- First, make sure you're on 2.5.x, as some
> > important changes
> > >were made post-2.4.
> > >
> > >OSG LOD nodes are exported; see FltExportVisitor.cpp line 210. The
> > >FltExportVisitor class does _not_ override apply(PagedLOD&), so
> > >PagedLOD nodes should be treated as regular LOD nodes for
> > purposes of
> > >export. This means they receive no additional special
> > interpretation or
> > >treatment (they don't write external reference records), and
> > it means they must "look like"
> > >LOD nodes (they must have actual subtree children; file
> > names alone are
> > >not sufficient).
> > >
> > >I hope that helps,
> > > -Paul
> > >
> > >
> > >
> > >
> > >> -----Original Message-----
> > >> From: [EMAIL PROTECTED]
> > >>
> >
> [EMAIL PROTECTED]','','','')">osg-users-bou
> > >> [EMAIL PROTECTED] On Behalf Of Brian
> > >> Sent: Monday, June 16, 2008 9:47 AM
> > >> To: [email protected]
> > >> Subject: [osg-users] OpenFlight exporter question
> > >>
> > >> Hi,
> > >>
> > >> I was trying to convert some OSG models to the FLT
> format but ran
> > >> into a little trouble with one of the models. Only part
> > of the model
> > >> was converted. The model's LOD nodes were not touched by the
> > >> converter. I noticed in an earlier message that paged
> LOD support
> > >> does not exist yet, so is it safe to assume that what I am
> > seeing is
> > >> a direct result of that?
> > >>
> > >> Thanks,
> > >> Brian
> > >> _______________________________________________
> > >> osg-users mailing list
> > >> [email protected]
> > >> http://lists.openscenegraph.org/listinfo.cgi/osg-users-opensce
> > >negraph.org
> > >
> >
> >
>
> _______________________________________________
> osg-users mailing list
> [email protected]
> http://lists.openscenegraph.org/listinfo.cgi/osg-users-opensce
negraph.org
>
> _______________________________________________
> osg-users mailing list
> [email protected]
> http://lists.openscenegraph.org/listinfo.cgi/osg-users-opensce
negraph.org
_______________________________________________
osg-users mailing list
[email protected]
http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
