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

I asked a similar question recently at the GIS StackExchange. I believe I have found a SQL-only solution, which is reproduced below:

Eventually found the answer at Spatial Ed's Blog.

SQL demonstrating the transform:

DECLARE @geom GEOMETRY = 'POLYGON ((0 0, 10 0, 10 10, 0 10, 0 0))';
DECLARE @geog GEOGRAPHY = @geom.MakeValid().STUnion(@geom.STStartPoint()).STAsText()

And excerpt from Ed's post:

The key to this behavior is the the STUnion() method. Since this is an OGC-based method, working on the entire geometry for a given feature, it forces polygons into the orientation required for the method - which just happens to be the one used for the Geography type [...]. This method illustrated is quite efficient, keeping overhead small [...].