[postgis-devel] 3D Index / 2D Index concerns

[Olivier Courtin]

On Mar 18, 2011, at 3:28 AM, Nicklas Avén wrote:


> Yo are right that the distance/intersects functions doesn't handle
> volumes. Me and Olivier discussed this question about how to know if  
> it
> is a volume or not some time ago. As I understand it now there is a  
> flag
> in new serialized form that will tell if it is a volume.

Yeap there's a IS_SOLID flag to reflect that a polyhedral or tin enclose
a solid (or not)

> I still don't
> know what the standards say. If I remember right Ilivier said that the
> standard wasn't ready yet. Am I right. If it should follow 2D I mean  
> it
> have to be a separate geometry type like the distinction between
> linestring and polygon. But that is not the case?

 From SQL/MM, 2D spatial functions must behave 2D even if input datas  
are 3D,
(Z is just ignored)

--
Olivier