/// <summary>
/// Returns a System.Collections.List if integer shape indecies
/// </summary>
/// <param name="mwShapefile">The MapWinGIS.Shapefile to find shapes from</param>
/// <param name="ShapeIndex">The integer shape index in shapefile of the shape to compare with</param>
/// <returns>A System.Collections.List of integers that are the shape indecies of shapes overlapping extents</returns>
public static List <int> ShapesWithIntersectingEnvelope(MapWinGIS.Shapefile mwShapefile, int ShapeIndex)
{
List <int> Shapelist = new List <int>();
MapWinGIS.Extents ext1, ext2;
ext1 = mwShapefile.QuickExtents(ShapeIndex);
for (int shp = 0; shp < mwShapefile.NumShapes; shp++)
{
if (shp == ShapeIndex)
{
continue;
}
ext2 = mwShapefile.QuickExtents(shp);
if (ext1.xMin >= ext2.xMax)
{
continue;
}
if (ext1.yMin >= ext2.yMax)
{
continue;
}
if (ext2.xMin >= ext1.xMax)
{
continue;
}
if (ext2.yMin >= ext1.yMax)
{
continue;
}
Shapelist.Add(shp);
}
return(Shapelist);
}
/// <summary>
/// Determines if two shapes in the same shapefile have rectangular extents that touch or intersect.
/// </summary>
/// <param name="mwShapefile">A MapWinGIS.Shapefile containing both shapes to compare</param>
/// <param name="ShapeIndex1">The integer index of the first shape</param>
/// <param name="ShapeIndex2">The integer index of the second shape</param>
/// <returns>Boolean, true if the extents overlap or touch</returns>
public static bool EnvelopeIntersect(MapWinGIS.Shapefile mwShapefile, int ShapeIndex1, int ShapeIndex2)
{
MapWinGIS.Extents ext1;
MapWinGIS.Extents ext2;
ext1 = mwShapefile.QuickExtents(ShapeIndex1);
ext2 = mwShapefile.QuickExtents(ShapeIndex2);
if (ext1.xMin >= ext2.xMax)
{
return(false);
}
if (ext1.yMin >= ext2.yMax)
{
return(false);
}
if (ext2.xMin >= ext1.xMax)
{
return(false);
}
if (ext2.yMin >= ext1.yMax)
{
return(false);
}
return(true);
}
