<div dir="ltr"><div><div>Hi,<br><br></div>I contacted Howard Butler, one of the developers of PDAL, about possibly providing some input on questions we have in this thread, and believe he is now subscribed to the list.<br>
<br></div>Howard, any ideas on a strategy for using PDAL in QGIS, e.g. via proposed
GDAL support, as a separate data provider, and/or utilizing its command
line utilities via a Processing plugin provider?<div><div><div><div class="gmail_extra"><br></div><div class="gmail_extra">Regards,<br clear="all"></div><div class="gmail_extra"><div><br>Larry</div>
<br><br><div class="gmail_quote">On Wed, Jan 29, 2014 at 7:48 AM, A Huarte <span dir="ltr"><<a href="mailto:ahuarte47@yahoo.es" target="_blank">ahuarte47@yahoo.es</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">
<div><div style="font-size:12pt;font-family:HelveticaNeue,Helvetica Neue,Helvetica,Arial,Lucida Grande,sans-serif"><div><span>But then we must preprocess the data before load it in QGIS</span></div><div><br></div><blockquote style="border-left:2px solid rgb(16,16,255);margin-left:5px;margin-top:5px;padding-left:5px">
<div style="font-family:HelveticaNeue,'Helvetica Neue',Helvetica,Arial,'Lucida Grande',sans-serif;font-size:12pt"> <div style="font-family:HelveticaNeue,'Helvetica Neue',Helvetica,Arial,'Lucida Grande',sans-serif;font-size:12pt">
<div dir="ltr"> <hr size="1"> <font face="Arial"> <b><span style="font-weight:bold">De:</span></b> Randal Hale <<a href="mailto:rjhale@northrivergeographic.com" target="_blank">rjhale@northrivergeographic.com</a>><br>
<b><span style="font-weight:bold">Para:</span></b> <a href="mailto:qgis-developer@lists.osgeo.org" target="_blank">qgis-developer@lists.osgeo.org</a> <br> <b><span style="font-weight:bold">Enviado:</span></b> Miércoles 29 de enero de 2014
14:49<br> <b><span style="font-weight:bold">Asunto:</span></b> Re: [Qgis-developer] Lidar data into QGIS<br> </font> </div> <div><br>Would LASTools add anything to the conversation? I do believe they <br clear="none">re-order the file (but I've not used it).<br clear="none">
<br clear="none"><br clear="none">-----------------<br clear="none">Randal Hale, GISP<br clear="none">North River Geographic Systems, Inc<br clear="none"><a shape="rect" href="http://www.northrivergeographic.com/" target="_blank">http://www.northrivergeographic.com</a><br clear="none">
<a href="tel:423.653.3611" value="+14236533611" target="_blank">423.653.3611</a> <a shape="rect" href="mailto:rjhale@northrivergeographic.com" target="_blank">rjhale@northrivergeographic.com</a><br clear="none"><mailto:<a shape="rect" href="mailto:rjhale@northrivergeographic.com" target="_blank">rjhale@northrivergeographic.com</a>><br clear="none">
twitter:rjhale<br clear="none"><a shape="rect" href="http://about.me/rjhale" target="_blank">http://about.me/rjhale</a><br clear="none"><br clear="none">On 01/29/2014 08:25 AM, Jean-Roc Morreale wrote:<br clear="none">> Most lidar files are not spatially ordered so with a sequential read <br clear="none">
> you will end up reading the whole file, it's like accessing a untiled <br clear="none">> unpyramided bigtiff : painful.<br clear="none">><br clear="none">> Le 2014-01-29 13:52, A Huarte a écrit :<br clear="none">
>> I think but using a quadtree approach there is a problem, and it is<br clear="none">>> none other than the construction of the quadtree itself for so big<br clear="none">>> data.<br clear="none">>><br clear="none">
>> IMHO I would use a specific provider (with a specific featureiterator)<br clear="none">>> reading sequentially the LAS file and discarding points before fetch<br clear="none">>> it to
renderer using the RectangleFilter of current FeatureRequest. It<br clear="none">>> avoid create many-many QgsFeature's that after are discarded in<br clear="none">>> renderer side.<br clear="none">>><br clear="none">
>> I use this technique in a personal viewer, and after first read of<br clear="none">>> file (the file is cached in SO), the following drawings are quite<br clear="none">>> fast.<br clear="none">>><br clear="none">
>> Alvaro<br clear="none">>><br clear="none">>>> -------------------------<br clear="none">>>> DE: Jean-Roc Morreale <<a shape="rect" href="mailto:jr.morreale@enoreth.net" target="_blank">jr.morreale@enoreth.net</a>><br clear="none">
>>> PARA: <a shape="rect" href="mailto:qgis-developer@lists.osgeo.org" target="_blank">qgis-developer@lists.osgeo.org</a><br clear="none">>>>
ENVIADO: Miércoles 29 de enero de 2014 13:32<br clear="none">>>> ASUNTO: Re: [Qgis-developer] Lidar data into QGIS<br clear="none">>>><br clear="none">>>> Can it performs fast enough to display hundred millions points or<br clear="none">
>>> billions at once ? Does it leverage a quadtree approach ?<br clear="none">>>><br clear="none">>>> Le 2014-01-29 12:55, A Huarte a écrit :<br clear="none">>>>> yes, it can be implemented on renderer level (Martin Dobias<br clear="none">
>>> propose<br clear="none">>>>> it) or on featureiterator level similar to current simplification<br clear="none">>>>> classes for line and polygons<br clear="none">>>>><br clear="none">
>>>> I think it is pending for a test of performance<br clear="none">>>>> Best Regards<br clear="none">>>>> Alvaro<br clear="none">>>><br clear="none">>>> _______________________________________________<br clear="none">
>>> Qgis-developer mailing list<br clear="none">>>> <a shape="rect" href="mailto:Qgis-developer@lists.osgeo.org" target="_blank">Qgis-developer@lists.osgeo.org</a><br clear="none">>>> <a shape="rect" href="http://lists.osgeo.org/mailman/listinfo/qgis-developer" target="_blank">http://lists.osgeo.org/mailman/listinfo/qgis-developer </a>[1]<br clear="none">
>><br clear="none">>><br clear="none">>><br clear="none">>> Links:<br clear="none">>> ------<br clear="none">>> [1] <a shape="rect" href="http://lists.osgeo.org/mailman/listinfo/qgis-developer" target="_blank">http://lists.osgeo.org/mailman/listinfo/qgis-developer</a><br clear="none">
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