Implements the algorithms required to compute the isValid()
method for Geometry. See the documentation for the various geometry types for a specification of validity.
- Version
- 1.7
void geos::operation::valid::IsValidOp::setSelfTouchingRingFormingHoleValid |
( |
bool |
p_isValid | ) |
|
|
inline |
Sets whether polygons using Self-Touching Rings to form holes are reported as valid. If this flag is set, the following Self-Touching conditions are treated as being valid:
- the shell ring self-touches to create a hole touching the shell
- a hole ring self-touches to create two holes touching at a point
The default (following the OGC SFS standard) is that this condition is not valid (false).
Self-Touching Rings which disconnect the the polygon interior are still considered to be invalid (these are invalid under the SFS, and many other spatial models as well). This includes:
- exverted ("bow-tie") shells which self-touch at a single point
- inverted shells with the inversion touching the shell at another point
- exverted holes with exversion touching the hole at another point
- inverted ("C-shaped") holes which self-touch at a single point causing an island to be formed
- inverted shells or exverted holes which form part of a chain of touching rings (which disconnect the interior)
- Parameters
-
p_isValid | states whether geometry with this condition is valid |