// Created on: 2015-06-30
// Created by: Anton POLETAEV
// Copyright (c) 2015 OPEN CASCADE SAS
//
// This file is part of Open CASCADE Technology software library.
//
// This library is free software; you can redistribute it and/or modify it under
// the terms of the GNU Lesser General Public License version 2.1 as published
// by the Free Software Foundation, with special exception defined in the file
// OCCT_LGPL_EXCEPTION.txt. Consult the file LICENSE_LGPL_21.txt included in OCCT
// distribution for complete text of the license and disclaimer of any warranty.
//
// Alternatively, this file may be used under the terms of Open CASCADE
// commercial license or contractual agreement.

#include <OpenGl_BVHClipPrimitiveTrsfPersSet.hxx>
#include <BVH_LinearBuilder.hxx>

// =======================================================================
// function : OpenGl_BVHClipPrimitiveTrsfPersSet
// purpose  :
// =======================================================================
OpenGl_BVHClipPrimitiveTrsfPersSet::OpenGl_BVHClipPrimitiveTrsfPersSet()
: myIsDirty (Standard_False),
  myBVH (new BVH_Tree<Standard_ShortReal, 4>())
{
  myBuilder = new BVH_LinearBuilder<Standard_ShortReal, 4> (1, 32);
}

// =======================================================================
// function : Size
// purpose  :
// =======================================================================
Standard_Integer OpenGl_BVHClipPrimitiveTrsfPersSet::Size() const
{
  return myStructs.Size();
}

// =======================================================================
// function : Box
// purpose  :
// =======================================================================
Graphic3d_BndBox4f OpenGl_BVHClipPrimitiveTrsfPersSet::Box (const Standard_Integer theIdx) const
{
  return *myStructBoxes (theIdx + 1);
}

// =======================================================================
// function : Center
// purpose  :
// =======================================================================
Standard_ShortReal OpenGl_BVHClipPrimitiveTrsfPersSet::Center (const Standard_Integer theIdx,
                                                               const Standard_Integer theAxis) const
{
  const Graphic3d_BndBox4f& aBndBox = *myStructBoxes (theIdx + 1);

  return (aBndBox.CornerMin()[theAxis] + aBndBox.CornerMax()[theAxis]) * 0.5f;
}

// =======================================================================
// function : Swap
// purpose  :
// =======================================================================
void OpenGl_BVHClipPrimitiveTrsfPersSet::Swap (const Standard_Integer theIdx1,
                                               const Standard_Integer theIdx2)
{
  const Standard_Integer aStructIdx1 = theIdx1 + 1;
  const Standard_Integer aStructIdx2 = theIdx2 + 1;

  myStructs    .Swap (aStructIdx1, aStructIdx2);
  myStructBoxes.Swap (aStructIdx1, aStructIdx2);
}

// =======================================================================
// function : Add
// purpose  :
// =======================================================================
Standard_Boolean OpenGl_BVHClipPrimitiveTrsfPersSet::Add (const OpenGl_Structure* theStruct)
{
  const Standard_Integer aSize = myStructs.Size();

  if (myStructs.Add (theStruct) > aSize) // new structure?
  {
    MarkDirty();

    return Standard_True;
  }

  return Standard_False;
}

// =======================================================================
// function : Remove
// purpose  :
// =======================================================================
Standard_Boolean OpenGl_BVHClipPrimitiveTrsfPersSet::Remove (const OpenGl_Structure* theStruct)
{
  const Standard_Integer anIndex = myStructs.FindIndex (theStruct);

  if (anIndex != 0)
  {
    myStructs.Swap (Size(), anIndex);
    myStructs.RemoveLast();
    MarkDirty();

    return Standard_True;
  }

  return Standard_False;
}

// =======================================================================
// function : Clear
// purpose  :
// =======================================================================
void OpenGl_BVHClipPrimitiveTrsfPersSet::Clear()
{
  myStructs.Clear();
  MarkDirty();
}

// =======================================================================
// function : GetStructureById
// purpose  :
// =======================================================================
const OpenGl_Structure* OpenGl_BVHClipPrimitiveTrsfPersSet::GetStructureById (Standard_Integer theId)
{
  return myStructs.FindKey (theId + 1);
}

//=======================================================================
// function : BVH
// purpose  :
//=======================================================================
const NCollection_Handle<BVH_Tree<Standard_ShortReal, 4> >&
  OpenGl_BVHClipPrimitiveTrsfPersSet::BVH (const OpenGl_Mat4& theProjectionMatrix,
                                           const OpenGl_Mat4& theWorldViewMatrix,
                                           const Graphic3d_WorldViewProjState& theWVPState)
{
  if (!myIsDirty
    && (myStructBoxesState.IsValid()
    && !myStructBoxesState.IsChanged (theWVPState)))
  {
    return myBVH;
  }

  myStructBoxes.ReSize (myStructs.Size());

  for (Standard_Integer aStructIdx = 1; aStructIdx <= myStructs.Size(); ++aStructIdx)
  {
    const OpenGl_Structure* aStructure = myStructs (aStructIdx);

    HBndBox4f aBoundingBox = new Graphic3d_BndBox4f;
    *aBoundingBox = aStructure->BoundingBox();
     aStructure->TransformPersistence.Apply (theProjectionMatrix, theWorldViewMatrix, 0, 0, *aBoundingBox);

    myStructBoxes.Add (aBoundingBox);
  }

  myBuilder->Build (this, myBVH.operator->(), BVH_Set<Standard_ShortReal, 4>::Box());

  myStructBoxesState = theWVPState;
  myStructBoxes.Clear();
  myIsDirty = Standard_False;

  return myBVH;
}