/// \file
/// \ingroup tutorial_eve
/// Demonstrates usage of 'cone' mode in TEveBoxSet class.
///
/// \image html eve_boxset_cones.png
/// \macro_code
///
/// \author Alja Mrak-Tadel

TEveBoxSet* boxset_cones(Float_t x=0, Float_t y=0, Float_t z=0,
                         Int_t num=100, Bool_t register=kTRUE)
{
   TEveManager::Create();

   using namespace TMath;

   auto lines = new TEveStraightLineSet("StraightLines");
   lines->SetLineColor(kYellow);
   lines->SetLineWidth(2);

   TRandom r(0);
   auto pal   = new TEveRGBAPalette(0, 500);
   auto cones = new TEveBoxSet("ConeSet");
   cones->SetPalette(pal);
   cones->Reset(TEveBoxSet::kBT_Cone, kFALSE, 64);

   Float_t a = 40; // max distance between cones
   TEveVector dir, pos;
   Float_t theta, phi, height, rad;
   for (Int_t i=0; i<num; ++i) {
      theta  = r.Uniform(0,TMath::Pi());
      phi    = r.Uniform (-TMath::Pi(), TMath::Pi());
      height = r.Uniform(5, 15);
      rad    = r.Uniform(3, 5);
      dir.Set(Cos(phi)*Cos(theta), Sin(phi)*Cos(theta), Sin(theta));
      dir *= height;
      pos.Set(r.Uniform(-a,a), r.Uniform(-a, a), r.Uniform(-a, a));

      cones->AddCone(pos, dir, rad);
      cones->DigitValue(r.Uniform(0, 500));

      // draw axis line 30% longer than cone height
      TEveVector end = pos + dir*1.3f;
      lines->AddLine(pos.fX, pos.fY, pos.fZ, end.fX, end.fY, end.fZ);
   }

   // by default cone cap not drawn
   if (r.Integer(2)>0)  cones->SetDrawConeCap(kTRUE);

   cones->RefitPlex();
   TEveTrans& t = cones->RefMainTrans();
   t.SetPos(x, y, z);

   gEve->AddElement(cones);
   gEve->AddElement(lines);

   gEve->Redraw3D(kTRUE);

   return cones;
}

TEveBoxSet* elliptic_boxset_cones(Float_t x=0, Float_t y=0, Float_t z=0,
                                  Int_t num=100, Bool_t register=kTRUE)
{
   TEveManager::Create();

   using namespace TMath;

   TEveManager::Create();

   auto lines = new TEveStraightLineSet("StraightLines");
   lines->SetLineColor(kYellow);
   lines->SetLineWidth(2);

   TRandom r(0);

   auto cones = new TEveBoxSet("EllipticConeSet");
   cones->Reset(TEveBoxSet::kBT_EllipticCone, kTRUE, 64);

   cones->SetPickable(kTRUE);

   Float_t a = 40; // max distance between cones
   TEveVector dir, pos;
   Float_t theta, phi, height, rad;
   for (Int_t i=0; i<num; ++i) {
      theta  = r.Uniform(0,TMath::Pi());
      phi    = r.Uniform (-TMath::Pi(), TMath::Pi());
      height = r.Uniform(5, 15);
      rad    = r.Uniform(3, 5);
      dir.Set(Cos(phi)*Cos(theta), Sin(phi)*Cos(theta), Sin(theta));
      dir *= height;
      pos.Set(r.Uniform(-a,a), r.Uniform(-a, a), r.Uniform(-a, a));

      cones->AddEllipticCone(pos, dir, rad, 0.5*rad, r.Uniform(0,360));
      cones->DigitColor(r.Uniform(20, 255), r.Uniform(20, 255),
                      r.Uniform(20, 255), r.Uniform(20, 255));

      // draw axis line 30% longer than cone height
      TEveVector end = pos + dir*1.3f;
      lines->AddLine(pos.fX, pos.fY, pos.fZ, end.fX, end.fY, end.fZ);
   }

   // by default cone cap not drawn
   if (r.Integer(2)>0)  cones->SetDrawConeCap(kTRUE);

   cones->RefitPlex();
   TEveTrans& t = cones->RefMainTrans();
   t.SetPos(x, y, z);

   gEve->AddElement(cones);
   gEve->AddElement(lines);

   gEve->Redraw3D(kTRUE);

   return cones;
}