has_kickbacks

Tests whether a geometry has kickbacks.

A kickback is defined to be four consecutive points (A, B, C, D) such that:

Parameter 1 - the geometry to be tested.

Parameter 2 (Optional) - the maximum value for the sine of the angles in the kickback. If omitted, this defaults to the sine of 1 degree.

Parameter 3 (Optional) - the maximum width of the kickback.

Returns: a Boolean value, true if the geometry has kickbacks and false if it does not. Returns null if parameter 1 is not a geometry.

Note: This function does not fully support 3D geometries. Any 3D geometries will be projected down to 2 dimensions.