// @(#)root/g3d:$Id: TPGON.cxx 20882 2007-11-19 11:31:26Z rdm $
// Author: Nenad Buncic   29/09/95

/*************************************************************************
 * Copyright (C) 1995-2000, Rene Brun and Fons Rademakers.               *
 * All rights reserved.                                                  *
 *                                                                       *
 * For the licensing terms see $ROOTSYS/LICENSE.                         *
 * For the list of contributors see $ROOTSYS/README/CREDITS.             *
 *************************************************************************/

#include "TPGON.h"
#include "TMath.h"

ClassImp(TPGON)

//______________________________________________________________________________
// Begin_Html <P ALIGN=CENTER> <IMG SRC="gif/pgon.gif"> </P> End_Html
// PGON is a polygon. It has the following parameters:
//
//     - name       name of the shape
//     - title      shape's title
//     - material  (see TMaterial)
//     - phi1       the azimuthal angle &phi at which the volume begins (angles
//                  are counted counterclockwise)
//     - dphi1      opening angle of the volume, which extends from phi1 to
//                  phi1+dphi
//     - npdv       number of sides of the cross section between the given
//                  phi limits
//     - nz         number of planes perpendicular to the z axis where
//                  the dimension of the section is given -- this number
//                  should be at least 2
//     - rmin       array of dimension nz with minimum radius at a given plane
//     - rmax       array of dimension nz with maximum radius at a given plane
//     - z          array of dimension nz with z position of given plane


//______________________________________________________________________________
TPGON::TPGON ()
{
   // PGON shape default constructor.
}


//______________________________________________________________________________
TPGON::TPGON (const char *name, const char *title, const char *material, Float_t phi1,
              Float_t dphi1, Int_t npdv, Int_t nz)
     : TPCON (name, title,material, phi1, dphi1, nz)
{
   // PGON shape normal constructor.
   //
   //  Parameters of the nz positions must be entered via TPCON::DefineSection.

   SetNumberOfDivisions (npdv);
}


//______________________________________________________________________________
TPGON::~TPGON ()
{
   // PGON shape default destructor.
}


//______________________________________________________________________________
void TPGON::FillTableOfCoSin(Double_t phi, Double_t angstep,Int_t n) const
{
   // Fill the table of cos and sin to prepare drawing

   Double_t factor = 1./TMath::Cos(angstep/2);
   Double_t ph = phi-angstep;
   for (Int_t j = 0; j < n; j++) {
      ph += angstep;
      fCoTab[j] = factor*TMath::Cos(ph);
      fSiTab[j] = factor*TMath::Sin(ph);
   }
}