The most important user level classes:
HxImageRep, HxImageFactory, HxImageSeq, HxHistogram, HxNJet, HxBSplineCurve, HxSampledBSplineCurve
Basic classes and types:
HxScalarInt, HxScalarDouble, HxVec2Int, HxVec2Double, HxVec3Int, and HxVec3Double.
HxPoint, HxPointInt, HxPointZ, HxPointList.h
HxMatrix, HxVector
Image related classes:
HxImageSignature, HxGeoIntType, HxSizes, HxTagList, HxValue, HxValueList.h, HxValueType