SQL Spatial polygon inside out

Question

I am allowing users to draw a polygon in Silverlight by clicking to draw. Then I loop through the points, convert them to longitude and latitude and then save to SQL (in a

Answer 1

You can check, if the result of the EnvelopeAngle() method for the geography was 180, then use the ReorientObject() function to correct it.

Here is the sample:

--A CW polygon
DECLARE @G3 GEOGRAPHY = 'POLYGON ((45 45, 44 45, 44 46, 45 46, 45 45))';    
SELECT @G3.EnvelopeAngle();                --180
SELECT @G3.ReorientObject().STAsText();    --POLYGON ((44 46, 44 45, 45 45, 45 46, 44 46))

EDIT as stated in the comments you can may correct current geometries, using a simple update command (in the case you are sure they are not correct):

UPDATE foo_table SET bar_column = bar_column.ReorientObject() 
    WHERE bar_column.EnvelopeAngle() > 90