class TGeoArb8: public TGeoBBox

 Default ctor.

 Constructor. If the array of vertices is not null, this should be
 in the format : (x0, y0, x1, y1, ... , x7, y7)

 Named constructor. If the array of vertices is not null, this should be
 in the format : (x0, y0, x1, y1, ... , x7, y7)

copy constructor

assignment operator

 Destructor.

 Computes capacity of the shape in [length^3].

 Computes bounding box for an Arb8 shape.

 Computes tangents of twist angles (angles between projections on XY plane
 of corresponding -dz +dz edges). Computes also if the vertices are defined
 clockwise or anti-clockwise.

 Get twist for segment I in range [0,3]

 Get index of the edge of the quadrilater represented by vert closest to point.
 If [P1,P2] is the closest segment and P is the point, the function returns the fraction of the
 projection of (P1P) over (P1P2). If projection of P is not in range [P1,P2] return -1.

 Compute normal to closest surface from POINT.

 Test if point is inside this shape.
 first check Z range

 Computes distance to plane ipl :
 ipl=0 : points 0,4,1,5
 ipl=1 : points 1,5,2,6
 ipl=2 : points 2,6,3,7
 ipl=3 : points 3,7,0,4

 Computes distance from outside point to surface of the shape.

 Compute distance from inside point to surface of the shape.

 Divide this shape along one axis.

 Get shape range on a given axis.

--- Fill vector param[4] with the bounding cylinder parameters. The order
 is the following : Rmin, Rmax, Phi1, Phi2
--- first compute rmin/rmax

 Fills real parameters of a positioned box inside this arb8. Returns 0 if successfull.

 Computes normal to plane defined by P1, P2 and P3

 Fills array with n random points located on the surface of indexed facet.
 The output array must be provided with a length of minimum 3*npoints. Returns
 true if operation succeeded.
 Possible index values:
    0 - all facets togeather
    1 to 6 - facet index from bottom to top Z

 Finds if a point in XY plane is inside the polygon defines by PTS.

 Prints shape parameters

 Computes the closest distance from given point to this shape.

 Estimate safety to lateral plane defined by segment iseg in range [0,3]
 Might be negative: plane seen only from inside.

 Save a primitive as a C++ statement(s) on output stream "out".

 Computes intersection points between plane at zpl and non-horizontal edges.

 Set all arb8 params in one step.
 param[0] = dz
 param[1] = x0
 param[2] = y0

 Creates arb8 mesh points

 Creates arb8 mesh points

  Set values for a given vertex.

 Fill size of this 3-D object

 Stream an object of class TGeoManager.