union2

Herror ::union2 ( Hobject Region1, Hobject Region2, Hobject *RegionUnion ) HRegion HRegion::Union2 ( const HRegionArray &Region2 ) const HRegionArray HRegionArray::Union2 ( const HRegionArray &Region2 ) const

Return the union of two regions.

::union2 computes the union of the region in Region1 with all regions in Region2. This means that ::union2 is not commutative!

Parameters

`Region1` (input_object)	region(-array) `->` Hobject: HRegion(Array)
Region for which the union with all regions in Region2 is to be computed.

`Region2` (input_object)	region(-array) `->` Hobject: HRegion(Array)
Regions which should be added to Region1.

`RegionUnion` (output_object)	region(-array) `->` Hobject : HRegion(Array)*
Resulting regions.
Number of elements: RegionUnion == Region1

Complexity

Let F be the sum of all areas of the input regions. Then the runtime complexity is O(F) * F).

Result

::union2 always returns H_MSG_TRUE. The behavior in case of empty input (no regions given) can be set via ::set_system('no_object_result',<Result>) and the behavior in case of an empty input region via ::set_system('empty_region_result',<Result>). If necessary, an exception handling is raised.

Possible Predecessors

::threshold, ::connection, ::regiongrowing, ::pouring

Possible Successors

::select_shape, ::disp_region

Alternatives

::union1

See also

::intersection, ::complement

Module

Region processing