// @(#)root/eve:$Id: TEveCalo3DGL.cxx 26772 2008-12-09 19:57:49Z matevz $
// Author: Matevz Tadel 2007

/*************************************************************************
 * Copyright (C) 1995-2007, 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 "TEveCalo3DGL.h"
#include "TEveCalo.h"

#include "TMath.h"
#include "TAxis.h"

#include "TGLRnrCtx.h"
#include "TGLSelectRecord.h"
#include "TGLIncludes.h"
#include "TGLUtil.h"
#include "TEveRGBAPalette.h"
#include "TEveUtil.h"

//______________________________________________________________________________
//
// OpenGL renderer class for TEveCalo3D.

ClassImp(TEveCalo3DGL);

//______________________________________________________________________________
TEveCalo3DGL::TEveCalo3DGL() :
   TGLObject(), fM(0)
{
   // Constructor.

   fMultiColor = kTRUE;
}

//______________________________________________________________________________
Bool_t TEveCalo3DGL::SetModel(TObject* obj, const Option_t* /*opt*/)
{
   // Set model object.

   if (SetModelCheckClass(obj, TEveCalo3D::Class())) {
      fM = dynamic_cast<TEveCalo3D*>(obj);
      return kTRUE;
   }
   return kFALSE;
}

//______________________________________________________________________________
void TEveCalo3DGL::SetBBox()
{
   // Set bounding box.

   // !! This ok if master sub-classed from TAttBBox
   SetAxisAlignedBBox(((TEveCalo3D*)fExternalObj)->AssertBBox());
}

//______________________________________________________________________________
Bool_t TEveCalo3DGL::ShouldDLCache(const TGLRnrCtx& rnrCtx) const
{
   // Override from TGLObject.
   // To account for large point-sizes we modify the projection matrix
   // during selection and thus we need a direct draw.

   if (rnrCtx.Highlight() || rnrCtx.Selection()) return kFALSE;
   return TGLObject::ShouldDLCache(rnrCtx);
}

//______________________________________________________________________________
inline void TEveCalo3DGL::CrossProduct(const Float_t a[3], const Float_t b[3],
                                       const Float_t c[3], Float_t out[3]) const
{
   // Calculate cross-product.

   const Float_t v1[3] = { a[0] - c[0], a[1] - c[1], a[2] - c[2] };
   const Float_t v2[3] = { b[0] - c[0], b[1] - c[1], b[2] - c[2] };

   out[0] = v1[1] * v2[2] - v1[2] * v2[1];
   out[1] = v1[2] * v2[0] - v1[0] * v2[2];
   out[2] = v1[0] * v2[1] - v1[1] * v2[0];
}

//______________________________________________________________________________
void TEveCalo3DGL::RenderGridEndCap() const
{
   // Render end cap grid.

   using namespace TMath;

   Float_t  rB = fM->GetBarrelRadius();
   Double_t zE = fM->GetEndCapPos();

   Float_t etaMin = fM->GetEtaMin();
   Float_t etaMax = fM->GetEtaMax();
   Float_t trans  = fM->GetTransitionEta();
   Float_t phiMin = fM->GetPhiMin();
   Float_t phiMax = fM->GetPhiMax();

   TAxis *ax = fM->GetData()->GetEtaBins();
   Int_t  nx = ax->GetNbins();
   TAxis *ay = fM->GetData()->GetPhiBins();
   Int_t  ny = ay->GetNbins();


   Float_t r, z, theta, phiU, phiL, eta;

   // eta slices
   for (Int_t i=1; i<nx; ++i)
   {
      eta = ax->GetBinLowEdge(i);
      if (Abs(eta) > trans && (eta > etaMin && eta < etaMax))
      {
         theta = TEveCaloData::EtaToTheta(eta);
         r = Abs(zE*Tan(theta));
         z = Sign(zE, ax->GetBinLowEdge(i));
         for (Int_t j=1; j<=ny; ++j)
         {
            phiL = ay->GetBinLowEdge(j);
            phiU = ay->GetBinUpEdge(j);
            if (TEveUtil::IsU1IntervalContainedByMinMax(phiMin, phiMax, phiL, phiU))
            {
               glVertex3f(r*Cos(phiL), r*Sin(phiL), z);
               glVertex3f(r*Cos(phiU), r*Sin(phiU), z);
            }
         }
      }
   }

   Float_t r1, r2;
   // phi slices front
   if (etaMax > trans)
   {
      r1 = zE*Tan(TEveCaloData::EtaToTheta(etaMax));
      if (etaMin < trans)
         r2 = rB;
      else
         r2 = zE*Tan(TEveCaloData::EtaToTheta(etaMin));

      for (Int_t j=0; j<ny; ++j)
      {
         phiL = ay->GetBinLowEdge(j);
         phiU = ay->GetBinUpEdge(j);
         if (TEveUtil::IsU1IntervalContainedByMinMax(phiMin, phiMax, phiL, phiU))
         {
            glVertex3f( r1*Cos(phiU), r1*Sin(phiU), zE);
            glVertex3f( r2*Cos(phiU), r2*Sin(phiU), zE);
            glVertex3f( r1*Cos(phiL), r1*Sin(phiL), zE);
            glVertex3f( r2*Cos(phiL), r2*Sin(phiL), zE);
         }
      }
   }

   // phi slices back
   if (etaMin < -trans)
   {
      r1 = zE*Tan(TEveCaloData::EtaToTheta(etaMin));
      if (etaMax > -trans)
         r2 = rB;
      else
         r2 = zE*Tan(TEveCaloData::EtaToTheta(etaMax));

      r1 = Abs(r1);
      r2 = Abs(r2);
      for (Int_t j=0; j<ny; ++j)
      {
         phiL = ay->GetBinLowEdge(j);
         phiU = ay->GetBinUpEdge(j);
         if (TEveUtil::IsU1IntervalContainedByMinMax(phiMin, phiMax, phiL, phiU))
         {
            glVertex3f(r1*Cos(phiU), r1*Sin(phiU), -zE);
            glVertex3f(r2*Cos(phiU), r2*Sin(phiU), -zE);
            glVertex3f(r1*Cos(phiL), r1*Sin(phiL), -zE);
            glVertex3f(r2*Cos(phiL), r2*Sin(phiL), -zE);
         }
      }
   }
}

//______________________________________________________________________________
void TEveCalo3DGL::RenderGridBarrel() const
{
   // Render barrel grid.
   
   using namespace TMath;

   Float_t etaMin = fM->GetEtaMin();
   Float_t etaMax = fM->GetEtaMax();
   Float_t trans  = fM->GetTransitionEta();
   Float_t phiMin = fM->GetPhiMin();
   Float_t phiMax = fM->GetPhiMax();

   Float_t rB = fM->GetBarrelRadius();
   TAxis *ax  = fM->GetData()->GetEtaBins();
   Int_t nx   = ax->GetNbins();
   TAxis *ay  = fM->GetData()->GetPhiBins();
   Int_t ny   = ay->GetNbins();

   Float_t z, theta, phiL, phiU, eta, x, y;

   // eta slices
   for(Int_t i=1; i<nx; i++)
   {
      eta = ax->GetBinLowEdge(i);
      if ((Abs(eta)<trans) && (etaMin < eta && eta < etaMax))
      {
         theta = TEveCaloData::EtaToTheta(eta);
         z  = rB/Tan(theta);
         for (Int_t j=1; j<=ny; j++)
         {
            phiU = ay->GetBinUpEdge(j);
            phiL = ay->GetBinLowEdge(j);
            if (TEveUtil::IsU1IntervalContainedByMinMax(phiMin, phiMax, phiL, phiU))
            {
               glVertex3f(rB*Cos(phiL), rB*Sin(phiL), z);
               glVertex3f(rB*Cos(phiU), rB*Sin(phiU), z);
            }
         }      
      }
   }

   // phi slices
   Float_t zF, zB;

   if (etaMin > -trans)
      zB = rB/Tan(TEveCaloData::EtaToTheta(etaMin));
   else 
      zB = -fM->GetEndCapPos();


   if (etaMax < trans)
      zF =  rB/Tan(TEveCaloData::EtaToTheta(etaMax));
   else
      zF = fM->GetEndCapPos();

   for (Int_t j=0; j<ny; j++)
   {
      phiU = ay->GetBinUpEdge(j);
      phiL = ay->GetBinLowEdge(j);
      if (TEveUtil::IsU1IntervalContainedByMinMax(phiMin, phiMax, phiL, phiU))
      {
         x = rB * Cos(phiL);
         y = rB * Sin(phiL);
         glVertex3f(x, y, zB);
         glVertex3f(x, y, zF);
         x = rB * Cos(phiU);
         y = rB * Sin(phiU);
         glVertex3f(x, y, zB);
         glVertex3f(x, y, zF);
      }
   }
}

//______________________________________________________________________________
void TEveCalo3DGL::RenderGrid(TGLRnrCtx & rnrCtx) const
{
   // Draw frame reading eta, phi axis.

   if (rnrCtx.Highlight() || rnrCtx.Selection()) return;

   TGLCapabilitySwitch lights_off(GL_LIGHTING, kFALSE);

   glBegin(GL_LINES);

   Float_t etaMin = fM->GetEtaMin();
   Float_t etaMax = fM->GetEtaMax();

   Float_t trans = fM->GetTransitionEta();
   if (etaMin < trans && etaMax > -trans)
   {
      RenderGridBarrel();
   }

   if (etaMax > trans || etaMin < -trans)
   {
      RenderGridEndCap();
   }

   glEnd();
}

//______________________________________________________________________________
void TEveCalo3DGL::RenderBox(const Float_t pnts[8]) const
{
   // Render box with given points.

   //    z
   //    |
   //    |
   //    |________y
   //   /  6-------7
   //  /  /|      /|
   // x  5-------4 |
   //    | 2-----|-3
   //    |/      |/
   //    1-------0
   //

   const Float_t *p = pnts;
   Float_t cross[3];

   // bottom: 0123
   glBegin(GL_POLYGON);
   CrossProduct(p+3, p+9, p, cross);
   glNormal3fv(cross);
   glVertex3fv(p);
   glVertex3fv(p+3);
   glVertex3fv(p+6);
   glVertex3fv(p+9);
   glEnd();
   // top:    7654
   glBegin(GL_POLYGON);
   CrossProduct(p+21, p+15, p+12, cross);
   glNormal3fv(cross);
   glVertex3fv(p+21);
   glVertex3fv(p+18);
   glVertex3fv(p+15);
   glVertex3fv(p+12);
   glEnd();
   // back:   0451
   glBegin(GL_POLYGON);
   CrossProduct(p+12, p+3, p, cross);
   glNormal3fv(cross);
   glVertex3fv(p);
   glVertex3fv(p+12);
   glVertex3fv(p+15);
   glVertex3fv(p+3);
   glEnd();
   //front :  3267
   glBegin(GL_POLYGON);
   CrossProduct(p+6, p+21, p+9, cross);
   glNormal3fv(cross);
   glVertex3fv(p+9);
   glVertex3fv(p+6);
   glVertex3fv(p+18);
   glVertex3fv(p+21);
   glEnd();
   // left:    0374
   glBegin(GL_POLYGON);
   CrossProduct(p+21, p, p+9, cross);
   glNormal3fv(cross);
   glVertex3fv(p);
   glVertex3fv(p+9);
   glVertex3fv(p+21);
   glVertex3fv(p+12);
   glEnd();
   // right:   1562
   glBegin(GL_POLYGON);
   CrossProduct(p+15, p+6, p+3, cross);
   glNormal3fv(cross);
   glVertex3fv(p+3);
   glVertex3fv(p+15);
   glVertex3fv(p+18);
   glVertex3fv(p+6);
   glEnd();
}

//______________________________________________________________________________
Float_t TEveCalo3DGL::RenderBarrelCell(const TEveCaloData::CellData_t &cellData, Float_t towerH, Float_t offset ) const
{
   // Render barrel cell.

   using namespace TMath;

   Float_t r1 = fM->GetBarrelRadius() + offset;
   Float_t r2 = r1 + towerH*Sin(cellData.ThetaMin());
   Float_t z1In, z1Out, z2In, z2Out;

   z1In  = r1/Tan(cellData.ThetaMax());
   z1Out = r2/Tan(cellData.ThetaMax());
   z2In  = r1/Tan(cellData.ThetaMin());
   z2Out = r2/Tan(cellData.ThetaMin());

   Float_t cos1 = Cos(cellData.PhiMin());
   Float_t sin1 = Sin(cellData.PhiMin());
   Float_t cos2 = Cos(cellData.PhiMax());
   Float_t sin2 = Sin(cellData.PhiMax());

   Float_t box[24];
   Float_t* pnts = box;
   // 0
   pnts[0] = r1*cos2;
   pnts[1] = r1*sin2;
   pnts[2] = z1In;
   pnts += 3;
   // 1
   pnts[0] = r1*cos1;
   pnts[1] = r1*sin1;
   pnts[2] = z1In;
   pnts += 3;
   // 2
   pnts[0] = r1*cos1;
   pnts[1] = r1*sin1;
   pnts[2] = z2In;
   pnts += 3;
   // 3
   pnts[0] = r1*cos2;
   pnts[1] = r1*sin2;
   pnts[2] = z2In;
   pnts += 3;
   //---------------------------------------------------
   // 4
   pnts[0] = r2*cos2;
   pnts[1] = r2*sin2;
   pnts[2] = z1Out;
   pnts += 3;
   // 5
   pnts[0] = r2*cos1;
   pnts[1] = r2*sin1;
   pnts[2] = z1Out;
   pnts += 3;
   // 6
   pnts[0] = r2*cos1;
   pnts[1] = r2*sin1;
   pnts[2] = z2Out;
   pnts += 3;
   // 7
   pnts[0] = r2*cos2;
   pnts[1] = r2*sin2;
   pnts[2] = z2Out;

   RenderBox(box);

   return offset + towerH*Sin(cellData.ThetaMin());

}// end RenderBarrelCell

//______________________________________________________________________________
Float_t TEveCalo3DGL::RenderEndCapCell(const TEveCaloData::CellData_t &cellData, Float_t towerH, Float_t offset ) const
{
   // Render an endcap cell.

   using namespace TMath;
   Float_t z1, r1In, r1Out, z2, r2In, r2Out;

   z1    = TMath::Sign(fM->fEndCapPos + offset, cellData.Eta());
   z2    = z1 + TMath::Sign(towerH, cellData.Eta());

   r1In  = z1*Tan(cellData.ThetaMin());
   r2In  = z2*Tan(cellData.ThetaMin());
   r1Out = z1*Tan(cellData.ThetaMax());
   r2Out = z2*Tan(cellData.ThetaMax());

   Float_t cos2 = Cos(cellData.PhiMin());
   Float_t sin2 = Sin(cellData.PhiMin());
   Float_t cos1 = Cos(cellData.PhiMax());
   Float_t sin1 = Sin(cellData.PhiMax());

   Float_t box[24];
   Float_t* pnts = box;
   // 0
   pnts[0] = r1In*cos1;
   pnts[1] = r1In*sin1;
   pnts[2] = z1;
   pnts += 3;
   // 1
   pnts[0] = r1In*cos2;
   pnts[1] = r1In*sin2;
   pnts[2] = z1;
   pnts += 3;
   // 2
   pnts[0] = r2In*cos2;
   pnts[1] = r2In*sin2;
   pnts[2] = z2;
   pnts += 3;
   // 3
   pnts[0] = r2In*cos1;
   pnts[1] = r2In*sin1;
   pnts[2] = z2;
   pnts += 3;
   //---------------------------------------------------
   // 4
   pnts[0] = r1Out*cos1;
   pnts[1] = r1Out*sin1;
   pnts[2] = z1;
   pnts += 3;
   // 5
   pnts[0] = r1Out*cos2;
   pnts[1] = r1Out*sin2;
   pnts[2] = z1;
   pnts += 3;
   // 6
   pnts[0] = r2Out*cos2;
   pnts[1] = r2Out*sin2;
   pnts[2] = z2;
   pnts += 3;
   // 7
   pnts[0] = r2Out*cos1;
   pnts[1] = r2Out*sin1;
   pnts[2] = z2;

   RenderBox(box);
   return offset+towerH*Cos(cellData.ThetaMin());
} // end RenderEndCapCell

//______________________________________________________________________________
void TEveCalo3DGL::DirectDraw(TGLRnrCtx &rnrCtx) const
{
   // GL rendering.

   RenderGrid(rnrCtx);

   if (fM->fCellIdCacheOK == kFALSE)
      fM->BuildCellIdCache();

   glPushAttrib(GL_ENABLE_BIT | GL_POLYGON_BIT);
   glEnable(GL_NORMALIZE);
   glEnable(GL_LIGHTING);

   fM->AssertPalette();

   TEveCaloData::CellData_t cellData;
   Float_t transEta = fM->GetTransitionEta();
   Float_t towerH;
   Int_t   prevTower = 0;
   Float_t offset = 0;

   if (rnrCtx.SecSelection()) glPushName(0);
   for (UInt_t i=0; i<fM->fCellList.size(); i++)
   {
      fM->fData->GetCellData(fM->fCellList[i], cellData);

      if (fM->fCellList[i].fTower != prevTower)
      {
         offset = 0;
         prevTower = fM->fCellList[i].fTower;
      }
      fM->SetupColorHeight(cellData.Value(fM->fPlotEt), fM->fCellList[i].fSlice, towerH);
      if (rnrCtx.SecSelection()) glLoadName(i);
      if (TMath::Abs(cellData.EtaMax()) < transEta)
         offset = RenderBarrelCell(cellData, towerH, offset);
      else
         offset = RenderEndCapCell(cellData, towerH, offset);
   }
   if (rnrCtx.SecSelection()) glPopName();

   glPopAttrib();
}

//______________________________________________________________________________
void TEveCalo3DGL::ProcessSelection(TGLRnrCtx & /*rnrCtx*/, TGLSelectRecord & rec)
{
   // Processes secondary selection from TGLViewer.

   if (rec.GetN() < 2) return;

   Int_t cellID = rec.GetItem(1);
   TEveCaloData::CellData_t cellData;
   fM->fData->GetCellData(fM->fCellList[cellID], cellData);

   printf("Tower selected in slice %d \n", fM->fCellList[cellID].fSlice);
   cellData.Dump();
}