// Correct a triangle whose exterior ring is oriented 
// counterclockwise
triangle is Polygon2D
Linestring2DAddPoint(triangle.Outline, -3.00, 1.00)
Linestring2DAddPoint(triangle.Outline, 1.00, -2.00)
Linestring2DAddPoint(triangle.Outline, 2.00, 2.00)
Linestring2DAddPoint(triangle.Outline, -3.00, 1.00)
Trace("GeometryIsValid(triangle) = " + GeometryIsValid(triangle)) // False

// Correction
corrected_triangle is Polygon2D
corrected_triangle = GeometryCorrect(triangle)
Trace("GeometryIsValid(corrected_triangle) = " + GeometryIsValid(corrected_triangle)) // True
Trace("GeometryIsValid(triangle) = " + GeometryIsValid(triangle)) 
// Still False: the geometry passed as a parameter is not modified