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Hi Robert,<br>
<br>
The glitches are purely visual. I have no overlapping ranges, my
problem is the opposite - when I'm moving towards a level and the
range switches, it takes a while to load the high level and the low
level is switched off. While loading, there is just empty space for
a while until the high level has been loaded and is visualized.<br>
<br>
Attached is an attempt to illustrate the problem. When moving from
position 1 to 2, the middle level is switched out and although the
high level is within its range it takes a while to load it, so there
is a hole until it's finally been loaded in 3. Note that I don't
have to move the viewer between 2 and 3, just wait for the loading.
I would want the middle level to be visible until the high level is
actually loaded.<br>
<br>
Maybe I'm misunderstanding something about PagedLOD, the database
pager, or how to create quad-tree scene graphs for it to work
properly? I have only developed these things myself before in other
projects, and actually not used PagedLOD until now.<br>
<br>
Regards,<br>
Andreas<br>
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<div class="moz-cite-prefix">On 2016-08-26 15:58, Robert Osfield
wrote:<br>
</div>
<blockquote
cite="mid:CAFN7Y+XQbx8YPMDS4pTdqpUE8RJ3XmfwDdnnEqcFZJdQf1w3HQ@mail.gmail.com"
type="cite">
<pre wrap="">Hi Andreas,
On 26 August 2016 at 12:09, Andreas Ekstrand
<a class="moz-txt-link-rfc2396E" href="mailto:andreas.ekstrand@remograph.com"><andreas.ekstrand@remograph.com></a> wrote:
</pre>
<blockquote type="cite">
<pre wrap="">Is there any way to avoid glitches in the PagedLOD during loading of the
higher level after the lower level has switched out?
</pre>
</blockquote>
<pre wrap="">
Are we talking just a visual glitch or a frame rate drop, or both?
</pre>
<blockquote type="cite">
<pre wrap="">When flying over my
quad-tree terrain the tiles are flickering and the background color is
visible a short while before the higher level has been loaded.
One can of course override and implement logic that waits to switch the
lower level of until the higher has been loaded, but maybe I have missed
some existing setting?
</pre>
</blockquote>
<pre wrap="">
The logic in PageLOD::traverse() that decides between which LOD's to
display depends entirely on the LOD ranges used for each child, if the
ranges are distinct then no two children of a single PageLOD will be
displayed at the same time.
If you built the database such that the PageLOD's overlap a bit then
you have a case where both a lower level of detail and higher level of
detail could be visible at once. Given your description this sounds
like it may be possibility. I wouldn't recommend building PageLOD
databases with overlapping LOD range though - they can abut but
shouldn't overlap.
The other possibility might be display latency, or if you have some
kinds of higher level effect for visually blending between LOD levels.
Robert.
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</pre>
</blockquote>
<br>
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