[postgis-users] WKT polygon and interior ring orientation

[Mark Cave-Ayland]

Sufficool, Stanley wrote:

> I assume you mean GEOGRAPHY type. The SQL 2008 GEOMETRY type does not
> suport spheroid projections/calculations.

Yes, sorry I meant geography rather than geometry. Doh.

> Does ring orientation matter when you are calculating point in poly?
> When you calc a point in poly, do you take the sum of vertex angles from
> point to poly vertex and if sum of angles is >= 360 then point is in
> poly?

I can't see that PIP should care too much about orientation. Some 
googling shows up this link though:

http://msdn.microsoft.com/en-us/library/bb964711.aspx

This implies that the restriction is related to functions that determine 
whether one thing is within another. Hmmm.


ATB,

Mark.

-- 
Mark Cave-Ayland
Sirius Corporation - The Open Source Experts
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