MapWinGeoProc:Topology2D:Polygon

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Polygon

Summary

A structure representing a single closed polygon. This would represent a single part of a polygon shape. No holes. Unlike a shapefile, this polygon does not list the first point again at the end. (This prevents confusion when adding points to the list.)

Fields

m_Points List of points. For normal use, please use Add_Point or Insert_Point to correctly handle extents and prevent duplicate entries

Methods

Add_Point This function has 2 overloads.
Add_Segment Appends the the givin line segment to the end of the polyline. We assume that if the first point in the segment is the same as the endpoint of the polygon, we don't need to add the first point.
ClosestPointOn In the 2D case, we can treat the edges of the extents as segments and use the segment distance equations to find the closest distance.
Constructor This function has 2 overloads.
Copy Returns a new instance of the Polygon class with the same values as this object.
Insert_Point This function has 2 overloads.
Insert_Segment Inserts a segment into a polyline. This will check the points of the segment and only add the points if they are not identical to what will become the adjacent points.
IntersectsWith This function has 5 overloads.
Invalidate Many properties are derived from the points. Generally, these are calculated once and cached. Most changes that can be made externally will automatically cause an invalidation to occur, so adding points, for instance, will force the perimeter to be recalculated. This forces such an invalidation so that the next time derived properties are queried, they will be recalculated.
mwShape_To_Polygon If a Shape has multiple parts, this will create a separate polyline for each part.
Polygon_To_mwShape Converts a list of polylines into a single multi-part shape
SegmentsWithin Returns a list of segments from the Polygon that are within the submitted extents.
ShortestPathTo In the 2D case, we can treat the edges of the extents as segments and use the segment distance equations to find the closest distance. This returns null if the shapes intersect.
ToSegments Will create a list of segment objects for the entire polygon
TouchesTheBoundaryOf This function has 2 overloads.

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This page has been accessed 1,554 times. This page was last modified on 11 December 2006, at 03:12.