use qhull to generate convex hulls from polygons and point sets
Use qhull from the University of
Minnesota Geometry Center to generate convex hulls from point
sets or polygons:
http://www.geom.umn.edu/software/download/qhull.html
local-copy of Version 2.5
If qhull is found in your environment a "ConvexHull" tool will
automatically get added to the toolbar of each ivtools drawing editor (except idraw).
up to ivtools add-ons