[osg-users] How to select OSGB tiles for current zoom?

[Chris Hanson]

I'm not sure which field you're really asking about, but you should be
looking at the PagedLOD and LOD classes, and their LOD ranges. There are
some class flags there that indicate how to interpret the LOD ranges.

I wrote some whitepapers on LOD and VPB/PagedLOD. You should probably read
them:

http://alphapixel.com/wp-content/uploads/2015/04/LOD-Level-of-detail-in-OpenSceneGraph-OSG.pdf


http://alphapixel.com/wp-content/uploads/2015/04/OpenSceneGraph-OSG-Virtual-Planet-Builder-VPB-OSGDEM.pdf






On Wed, Sep 18, 2019 at 1:43 PM <shlem at netvision.net.il> wrote:

> Thank you for the answer.
> Can you point me to appropriate class/field name in osg
>
> *From:* Chris Hanson
> *Sent:* Wednesday, September 18, 2019 22:28
> *To:* OpenSceneGraph Users
> *Subject:* Re: [osg-users] How to select OSGB tiles for current zoom?
>
> Those max screen diameter values are using by projecting the diameter of
> the bounding sphere (usually encoded in any Group-derived nodes) through
> the modelview/projection matrix to assess its on-screen extent in pixels.
> If it is above or below the threshold defined by the max screen diameter
> field, that triggers a change in the selection of children.
>
> On Wed, Sep 18, 2019 at 12:55 PM <shlem at netvision.net.il> wrote:
>
>> Hi
>> I wrote my own renderer based on DirectX.
>> Everything goes nice except one issue.
>> How I decide to show the some tile/node or its children regarding to
>> current zoom level?
>> Does each tile/none have some hints? (like 3mx files for example, that
>> have  MaxScreenDiameter field)
>> Thanks in advance
>> Leonid Shikhmatov
>> _______________________________________________
>> osg-users mailing list
>> osg-users at lists.openscenegraph.org
>> http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
>>
>
>
> --
> Chris 'Xenon' Hanson, omo sanza lettere. Xenon at AlphaPixel.com
> http://www.alphapixel.com/
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-- 
Chris 'Xenon' Hanson, omo sanza lettere. Xenon at AlphaPixel.com
http://www.alphapixel.com/
Training • Consulting • Contracting
3D • Scene Graphs (Open Scene Graph/OSG) • OpenGL 2 • OpenGL 3 • OpenGL 4 •
GLSL • OpenGL ES 1 • OpenGL ES 2 • OpenCL
Legal/IP • Forensics • Imaging • UAVs • GIS • GPS •
osgEarth • Terrain • Telemetry • Cryptography • LIDAR • Embedded • Mobile •
iPhone/iPad/iOS • Android
@alphapixel <https://twitter.com/alphapixel> facebook.com/alphapixel (775)
623-PIXL [7495]
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