GISHullActorJ
org.ecoinformatics.seek.gis.java_gis.GISHullActorJ

The purpose of this actor is to take a set of (x, y) points and return the points that define the convex hull around the input. The convex hull can be thought of as the region defined by a 'rubber band' placed around the original data set. It is a sort of smallest polygon surrounding the input. The ConvexHull routine is implemented in Java and is thus portable to any java-enabled system. This actor is designed to have the same functionality as the JNI basedGISHullActor
'pointFileName' is a tab delimited text file with x,y input points
'hullFileName' is the name to be given to the hull point list file
'numHullPoint' is the number of x,y pairs in the hull file
'hullFileResult' is the output hull file name (same value as the 'hullFileName' but used as a trigger for output
There is also a 'scaleFactorParameter'. This is the scale factor for an AffineTransformation of the shape created by the ConvexHull. The convexHull shape is scaled by this factor (linearly), centered on the center of the convexhull bounding rectangle. The scale by area, set the scalefactor to the square root of the area scaling factor (i.e. to make a shape with twice the area, set the scale factor to SQRT(2) )
Note: if the scaleFactorParameter is empty or not a number, no scaling will be done.

Author(s):
Version:


pointFileName
'pointFileName' is a tab delimited text file with x,y input points

hullFileName
'hullFileName' is the name to be given to the hull point list file

numHullPoint
'numHullPoint' is the number of x,y pairs in the hull file


hullFileResult
'hullFileResult' is the output hull file name (same value as the 'hullFileName' but used as a trigger for output



scaleFactorParameter
This is the scale factor for an AffineTransformation of the shape created by the ConvexHull. The convexHull shape is scaled by this factor (linearly), centered on the center of the convexhull bounding rectangle. The scale by area, set the scalefactor to the square root of the area scaling factor (i.e. to make a shape with twice the area, set the scale factor to SQRT(2) )