Name

---

      POLYGON_ROI__DEFINE

Purpose

---

      The purpose of this routine is to create a polygon ROI drawing
      interaction. When the interaction is in place, the user can
      draw a polygon ROI in the display window.

Authors

---

        FANNING SOFTWARE CONSULTING BURRIDGE COMPUTING
        1645 Sheely Drive 18 The Green South
        Fort Collins Warborough, Oxon
        CO 80526 USA OX10 7DN, ENGLAND
        Phone: 970-221-0438 Phone: +44 (0)1865 858279
        E-mail: davidf@dfanning.com E-mail: davidb@burridgecomputing.co.uk

Category

---

      Objects.

Syntax

---

      theObject = Obj_New("POLYGON_ROI")

Superclasses

---

      FREEHAND_ROI
      INTERACTION
      CATATOM
      CATCONTAINER IDLITCOMPONENT
      IDL_CONTAINER

Class Structure

---

  class = { POLYGON_ROI, $
            pointsID: Obj_New(), $ ; A pixmap for the selected points.
            INHERITS FREEHAND_ROI $
          }

Messages

---

  None.

Event Structure

---

      event = { ID:theObject, TOP:topObject, HANDLER:Obj_New(), EVENT_NAME='POLYGON_ROI_EVENT', $
                  NAME: self._name, XPTS:FLTARR(), YPTS:FLATARR(), COUNT:0L }
      In which the XPTS and YPTS fields contain the X and Y locations of the polygon in a form
      suitable for drawing the ROI on the display with PLOTS. The COUNT field contains the number
      of points in the XPTS and YPTS vectors. The XPTS and YPTS are converted to the coordinate
      system of the draw widget associated with the interaction before being placed in the event structure.

Modification History

---

      Written by: David W. September 12, 2004.