The IDLanROI::ContainsPoints function method determines whether the given data coordinates are contained within the closed polygon region.


Result = Obj->[IDLanROI::]ContainsPoints( X [, Y [, Z]] )

Return Value

The return value is a vector of values, one per provided point, indicating whether that point is contained. Valid values within this return vector include:

  • 0 = Exterior. The point lies strictly out of bounds of the ROI
  • 1 = Interior. The point lies strictly inside the bounds of the ROI
  • 2 = On edge. The point lies on an edge of the ROI boundary
  • 3 = On vertex. The point matches a vertex of the ROI

A point is considered to be exterior if:

  • The point falls within the boundary of an interior region (hole)
  • The point does not lie in the plane of the region
  • The region TYPE property is set to 0 (points) or 1 (path)



A vector providing the X components of the points to be tested. If the Y and Z arguments are not specified, X must be a two-dimensional array with the leading dimension either 2 or 3 ([2,*] or [3,*]), in which case, X[0,*] represents the X values, X[1,*] represents the Y values, and X[2,*] represents the Z values.


A vector providing the Y components of the points to be tested.


A scalar or vector providing the Z component(s) of the points to be tested. If not provided, the Z components default to 0.0.




See "Testing an ROI for Point Containment" (Chapter 6, Image Processing in IDL in the help/pdf directory of your IDL installation).

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