Add some class docs.

[u/mrichter/AliRoot.git] / EVE / Reve / GridStepper.cxx

// $Header$

#include "GridStepper.h"
#include "ZTrans.h"

using namespace Reve;

//______________________________________________________________________
// GridStepper
//
// Provide position coordinates for regular-grid placement of objects.
//

ClassImp(GridStepper)

GridStepper::GridStepper(Int_t sm) :
  Mode(StepMode_e(sm)),
  nx(0), ny(0), nz(0), Nx(0), Ny(0), Nz(0),
  Dx(0), Dy(0), Dz(0), Ox(0), Oy(0), Oz(0)
{
  switch(Mode) {
  default:
  case SM_XYZ:
    ls[0] = &Nx; ls[1] = &Ny; ls[2] = &Nz;
    ns[0] = &nx; ns[1] = &ny; ns[2] = &nz;
    break;
  case SM_YXZ:
    ls[0] = &Ny; ls[1] = &Nx; ls[2] = &Nz;
    ns[0] = &ny; ns[1] = &nx; ns[2] = &nz;
    break;
  case SM_XZY:
    ls[0] = &Nx; ls[1] = &Nz; ls[2] = &Ny;
    ns[0] = &nx; ns[1] = &nz; ns[2] = &ny;
    break;
  }

  nx = ny = nz = 0;
  Nx = Ny = Nz = 16;
  Dx = Dy = Dz = 1;
  Ox = Oy = Oz = 0;
}

void GridStepper::Reset()
{
  nx = ny = nz = 0;
}

void GridStepper::Subtract(GridStepper& s)
{
  Ox = -(s.Ox + s.nx*s.Dx);
  Oy = -(s.Oy + s.ny*s.Dy);
  Oz = -(s.Oz + s.nz*s.Dz);
}
/**************************************************************************/

Bool_t GridStepper::Step()
{
  (*ns[0])++;
  if (*ns[0] >= *ls[0]) {
    *ns[0] = 0; (*ns[1])++;
    if (*ns[1] >= *ls[1]) {
      *ns[1] = 0; (*ns[2])++;
      if (*ns[2] >= *ls[2]) {
	return kFALSE;
      }
    }
  }
  return kTRUE;
}

/**************************************************************************/

void GridStepper::GetPosition(Float_t* p)
{
  p[0] = Ox + nx*Dx; p[1] = Oy + ny*Dy; p[2] = Oz + nz*Dz;
}

void GridStepper::SetTrans(ZTrans* mx)
{
  mx->SetPos(Ox + nx*Dx, Oy + ny*Dy, Oz + nz*Dz);
}

void GridStepper::SetTransAdvance(ZTrans* mx)
{
  SetTrans(mx);
  Step();
}