globalmapper.SpatialConvexHull
==============================

.. currentmodule:: globalmapper
.. py:function:: SpatialConvexHull (GM_LayerHandle_t32 aLayer, GM_SpatialOps_Params_t aParams, GM_FeatureGrouping_t8 aGrouping, str aStr) -> GM_Error_t32

	The **Convex Hull** operation creates a new layer with a polygon that encloses a set of points, lines, and/or areas.
	The polygon will be the smallest possible convex polygon that contains the features in the input layer; the
	shape of a convex hull is analogous to wrapping the features with a rubber band.

	The *aGrouping* parameter controls how many polygons are created: with *GM_GroupingNone*, a polygon is created for
	each individual feature; with *GM_GroupingPartition*, one polygon will be created for each attribute group; and with
	*GM_GroupingAll*, all the features on the layer will be enclosed by one polygon.

	For an even tighter fit hull, see :doc:`SpatialConcaveHull <globalmapper.SpatialConcaveHull>`.

	:param GM_LayerHandle_t32 aLayer: Input layer
	:param GM_SpatialOps_Params_t aParams: Parameters
	:param GM_FeatureGrouping_t8 aGrouping: Grouping type
	:param str aStr: The attribute list string; may be an empty string
	:returns: Error Code
	:rtype: GM_Error_t32