[Qgis-developer] 3D Points

[Marco Hugentobler]

Hi Matthew

There is already support for 3D points. I'm using it e.g. in the interpolation 
plugin / analysis library to do interpolation from 2.5D shapefiles. I haven't 
tried it with postgis, but suppose that it works too.

But afaik, you cannot access the z-coordinate with QgsPoint. You need to check 
if the geometry is a 2.5D type and parse the WKB to get it (see e.g. 
qgstininterpolator.cpp:204)

Point3D is a point type in the interpolation code. But it comes originally 
from external code, so cannot be used together with the core classes.


Regards,
Marco


Am Samstag, 26. Dezember 2009 15.36:03 schrieb Matthew Denno:
> Just a quick question because I am curious.  Is the next version (1.4)
>  going to have support for 3D points?  I see a Point3D class in the
>  documentation. Right now my app uses OGR dirctly for this but I didn't
>  want to do it that way.  Also, what is the difference between a Point25D
>  and Point3D?
> 
> Matt
> 

-- 
Dr. Marco Hugentobler
HUGIS - GIS programming and consulting
Webereistr. 66
CH-8134 Zürich
marco at hugis.net
http://homepage.hispeed.ch/hugis/
Technical Advisor QGIS Project Steering Committee