[OSM-talk] Tagging of areas with holes

[Jon Burgess]

On Wed, 2007-10-31 at 16:40 +0100, Dirk-Lüder Kreie wrote:
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> David Groom schrieb:
> 
> > 2) The main area to be anticlockwise, and the hole to be drawn clockwise.
> 
> This is the exact opposite of what we tried to define for an area for
> coastlines.
> However for the renderers it *should* suffice to have the areas
> orientated differently, without care for absolute orientation
> (either outer=CW and inner=CCW or outer=CCW and inner=CW)

As you say. The conventional wisdom was that the outer ring should be in
a clockwise direction and the holes counter clockwise. 

I have not tried any tests recently but in the past things would
occasionally render incorrectly if you did not follow these rules.

	Jon