tom & others,<br><br>my quad tree finalization can code could only be used to tile the data adaptively (with a min or max num of points per quad tree cell).<br><br>but with some extra care taken the same code will also be able to allow TIN streaming sometime later. that would mean that an oracle point cloud generated with this quad tree code would remain "implicitly finalized" if we keep some basic info around. both "lastile" and "lassort" use a variation of this quad tree code as well. currently the quad tree is just used for tiling and z-order sorting ... but resulting LAS file are also spatially finalized and could be fed into a streaming pipeline.<br>
<br><a href="http://www.cs.unc.edu/~isenburg/lastools/download/lastile_README.txt">http://www.cs.unc.edu/~isenburg/lastools/download/lastile_README.txt</a><br><a href="http://www.cs.unc.edu/~isenburg/lastools/download/lassort_README.txt">http://www.cs.unc.edu/~isenburg/lastools/download/lassort_README.txt</a><br>
<br>If it is of interest to (someday) be able to use the point clouds reordered by libLAS or libPC together with TIN streaming it may be worthwhile to take that extra care and add a compatible quad tree functionality to the libraries. Streaming TIN generation relies on overlap tests between circles and quad-tree cells (which are very very tricky to get right due to floating-point arithmetic error offsets [1]) so that switching to a different quad tree code won't be trivial.<br>
<br>cheers,<br><br>martin @lastools<br><br>[1] Martin Isenburg, Yuanxin Liu, Jonathan Shewchuk, Jack Snoeyink, Streaming Computation of Delaunay Triangulations, Proceedings of SIGGRAPH'06, pages 1049-1056, July 2006. <a href="http://www.cs.unc.edu/~isenburg/sd/">http://www.cs.unc.edu/~isenburg/sd/</a><br>
<br><div class="gmail_quote">On Mon, Apr 18, 2011 at 7:18 AM, Michael P. Gerlek <span dir="ltr"><<a href="mailto:mpg@flaxen.com">mpg@flaxen.com</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin: 0pt 0pt 0pt 0.8ex; border-left: 1px solid rgb(204, 204, 204); padding-left: 1ex;">
<div class="im">> Of course I am willing to provide the source code. Mostly is copied/based<br>
on<br>
> SPfinalizer. To whom and where could I send the source to?<br>
<br>
</div>Tom:<br>
<br>
When you say "copied", do you mean you directly used Martin's source code?<br>
If so, we cannot accept you contribution, unless Martin's code is also open<br>
source with an OSI-approved license on it (preferably BSD). The provenance<br>
of much of Martin's code is not clear, and libLAS/libPC has to be very<br>
careful about where we get our code from. If you only based your code on<br>
something like a published paper of his, however, that would be okay.<br>
<br>
That being said, if your code meets these requirements then please just make<br>
sure your copyright appears on each of the files and you can send it to me<br>
(<a href="mailto:mpg@flaxen.com">mpg@flaxen.com</a>).<br>
<br>
Thanks -<br>
<font color="#888888"><br>
-mpg<br>
</font><div><div></div><div class="h5"><br>
<br>
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