[gdal-dev] Support of filemapping for fast rendering in QGIS...

[Even Rouault]

> On the other hand, this provider may also accelerate with some small
> changes that are pending of review in the ticket
> (http://trac.osgeo.org/gdal/ticket/5272) that I hope will be evaluated.

Actually when thinking about the atof() optimization, a far better idea would 
be to make sure that QGIS uses OGR_L_SetIgnoredFields() with all the regular 
field names as parameter (except the fields it might use for styling), when it 
just needs the geometry. So no slow or fast atof() at all will be needed. In 
my old copy of QGis git, I see a QgsOgrProvider::setRelevantFields() method 
that is supposed to do something in that area. Something that you should be 
investigated more. You don't need to read 8 double fields just for rendering.

Even

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