Package org.tinfour.utils

Class SmoothingFilter

  • All Implemented Interfaces:
    IVertexValuator
    public class SmoothingFilter
extends Object
implements IVertexValuator
    An implementation of the vertex valuator that processes the vertices in a Constrained Delaunay Triangulation and applies a low-pass filter over the data.

    Note that this class modifies the index values of the vertices stored in the TIN. It also depends on the modified values as a way of tracking vertices. Therefore, calling applications should not modify these values while the smoothing filter is being used.

    • Constructor Detail

      • SmoothingFilter

        public SmoothingFilter​(IIncrementalTin tin)
        Construct a smoothing filter. Note that this class modifies the index values of the vertices stored in the TIN.

        Important usage note: this constructor modifies the index values of the vertices stored in the TIN. It also depends on the modified values as a way of tracking vertices. Therefore, calling applications should not modify these values while the smoothing filter is being used.

        The vertices belonging to constraints are not smoothed, but are represented with their original values by the smoothing filter.

        Parameters:
        tin - a valid Delaunay Triangulation

      • SmoothingFilter

        public SmoothingFilter​(IIncrementalTin tin,
                       int nPass)
        Construct a smoothing filter. Note that this class modifies the index values of the vertices stored in the TIN.

        Important usage note: this constructor modifies the index values of the vertices stored in the TIN. It also depends on the modified values as a way of tracking vertices. Therefore, calling applications should not modify these values while the smoothing filter is being used.

        The vertices belonging to constraints are not smoothed, but are represented with their original values by the smoothing filter.

        The number of passes determines the degree to which features are smoothed. The best choice for this value depends on the requirements of the application. Values in the range 5 to 40 are good candidates for investigation.

        Parameters:
        tin - a valid Delaunay Triangulation
        nPass - the number of passes the filter performs over the vertices during smoothing.

    • Method Detail

      • getTimeToConstructFilter

        public double getTimeToConstructFilter()
        Gets the time required to construct the filter, in milliseconds. Intended for diagnostic and development purposes.
        Returns:
        a value in milliseconds.

      • value

        public double value​(Vertex v)
        Description copied from interface: IVertexValuator
        Given a vertex v, obtain its value
        Specified by:
        value in interface IVertexValuator
        Parameters:
        v - a vertex
        Returns:
        a value interpreted from vertex v.

      • getVertexAdjustments

        public double[] getVertexAdjustments()
        Gets the array of adjustment for vertices.
        Returns:
        a valid array.

      • setVertexAdjustments

        public void setVertexAdjustments​(double[] adjustments)
        Sets the array of adjustments for vertices
        Parameters:
        adjustments - a valid array of same length as internal storage

      • getMinZ

        public double getMinZ()
        Gets the minimum value from the set of possible values. Due to the smoothing, this value may be larger than the minimum input value.
        Returns:
        a valid floating-point value.

      • getMaxZ

        public double getMaxZ()
        Gets the maximum value from the set of possible values. Due to the smoothing, this value may be smaller than the maximum input value.
        Returns:
        a valid floating-point value.