REveBox.cxx

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// @(#)root/eve:$Id$
// Author: Matevz Tadel, 2010
 
/*************************************************************************
 * 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 <ROOT/REveBox.hxx>
#include <ROOT/REveProjectionManager.hxx>
#include <ROOT/REveRenderData.hxx>
#include <ROOT/REveTrans.hxx>
 
#include "TClass.h"
 
#include <nlohmann/json.hpp>
 
using namespace ROOT::Experimental;
 
/** \class REveBox
\ingroup REve
3D box with arbitrary vertices (cuboid).
Vertices 0-3 specify the "bottom" rectangle in clockwise direction and
vertices 4-7 the "top" rectangle so that 4 is above 0, 5 above 1 and so on.
 
If vertices are provided some local coordinates the transformation matrix
of the element should also be set (but then the memory usage is increased
by the size of the REveTrans object).
 
Currently only supports 3D -> 2D projections.
*/
 
 
////////////////////////////////////////////////////////////////////////////////
/// Constructor.
 
REveBox::REveBox(const char* n, const char* t) :
   REveShape(n, t)
{
}
 
////////////////////////////////////////////////////////////////////////////////
/// Destructor.
 
REveBox::~REveBox()
{
}
 
////////////////////////////////////////////////////////////////////////////////
/// Set vertex 'i'.
 
void REveBox::SetVertex(Int_t i, Float_t x, Float_t y, Float_t z)
{
   fVertices[i][0] = x;
   fVertices[i][1] = y;
   fVertices[i][2] = z;
   ResetBBox();
}
 
////////////////////////////////////////////////////////////////////////////////
/// Set vertex 'i'.
 
void REveBox::SetVertex(Int_t i, const Float_t* v)
{
   fVertices[i][0] = v[0];
   fVertices[i][1] = v[1];
   fVertices[i][2] = v[2];
   ResetBBox();
}
 
////////////////////////////////////////////////////////////////////////////////
/// Set vertices.
 
void REveBox::SetVertices(const Float_t* vs)
{
   memcpy(fVertices, vs, sizeof(fVertices));
   ResetBBox();
}
 
 
////////////////////////////////////////////////////////////////////////////////
/// Compute bounding-box of the data.
 
void REveBox::ComputeBBox()
{
   REveShape::CheckAndFixBoxOrientationFv(fVertices);
 
   BBoxInit();
   for (Int_t i=0; i<8; ++i)
   {
      BBoxCheckPoint(fVertices[i]);
   }
}
 
 
////////////////////////////////////////////////////////////////////////////////
/// Fill core part of JSON representation.
 
Int_t REveBox::WriteCoreJson(nlohmann::json &j, Int_t rnr_offset)
{
   Int_t ret = REveElement::WriteCoreJson(j, rnr_offset);
 
   j["fMainColor"] = GetFillColor();
   j["fLineColor"] = GetLineColor();
 
   return ret;
}
 
////////////////////////////////////////////////////////////////////////////////
/// Crates 3D point array for rendering.
 
void REveBox::BuildRenderData()
{
   int N = 8;
   fRenderData = std::make_unique<REveRenderData>("makeBox", N*3);
   for (Int_t i = 0; i < N; ++i)
   {
      fRenderData->PushV(fVertices[i][0], fVertices[i][1], fVertices[i][2]);
   }
}
 
 
////////////////////////////////////////////////////////////////////////////////
/// Virtual from REveProjectable, return REveBoxProjected class.
 
TClass* REveBox::ProjectedClass(const REveProjection*) const
{
   return TClass::GetClass<REveBoxProjected>();
}
 
 
/** \class REveBoxProjected
\ingroup REve
Projection of REveBox.
*/
 
 
////////////////////////////////////////////////////////////////////////////////
/// Constructor.
 
REveBoxProjected::REveBoxProjected(const char* n, const char* t) :
   REveShape(n, t),
   fBreakIdx(0),
   fDebugCornerPoints(false)
{
}
 
////////////////////////////////////////////////////////////////////////////////
/// Destructor.
 
REveBoxProjected::~REveBoxProjected()
{
}
 
////////////////////////////////////////////////////////////////////////////////
/// Fill the bounding box (virtual from REveElement).
 
void REveBoxProjected::ComputeBBox()
{
   BBoxInit();
   for (auto &pnt: fPoints)
      BBoxCheckPoint(pnt.fX, pnt.fY, fDepth);
}
 
////////////////////////////////////////////////////////////////////////////////
/// This is virtual method from base-class REveProjected.
 
void REveBoxProjected::SetDepthLocal(Float_t d)
{
   SetDepthCommon(d, this);
}
 
////////////////////////////////////////////////////////////////////////////////
/// This is virtual method from base-class REveProjected.
 
void REveBoxProjected::SetProjection(REveProjectionManager* mng, REveProjectable* model)
{
   REveProjected::SetProjection(mng, model);
   CopyVizParams(dynamic_cast<REveElement*>(model));
}
 
////////////////////////////////////////////////////////////////////////////////
/// Re-project the box. Projects all points and finds 2D convex-hull.
///
/// The only issue is with making sure that initial conditions for
/// hull-search are reasonable -- that is, there are no overlaps with the
/// first point.
 
void REveBoxProjected::UpdateProjection()
{
   REveBox *box = dynamic_cast<REveBox*>(fProjectable);
 
   fDebugPoints.clear();
 
   // Project points in global CS, remove overlaps.
   vVector2_t pp[2];
   {
      REveProjection *projection = fManager->GetProjection();
      REveTrans mt;
      const REveTrans *trans = fManager->GetModelTrans(box, mt);
 
      REveVector pbuf;
      for (Int_t i = 0; i < 8; ++i)
      {
         projection->ProjectPointfv(trans, box->GetVertex(i), pbuf, fDepth);
         vVector2_t& ppv = pp[projection->SubSpaceId(pbuf)];
 
         REveVector2 p(pbuf);
         Bool_t      overlap = kFALSE;
         for (auto &j: ppv)
         {
            if (p.SquareDistance(j) < REveProjection::fgEpsSqr)
            {
               overlap = kTRUE;
               break;
            }
         }
         if (! overlap)
         {
            ppv.push_back(p);
            if (fDebugCornerPoints)
               fDebugPoints.push_back(p);
         }
      }
   }
 
   fPoints.clear();
   fBreakIdx = 0;
 
   if ( ! pp[0].empty())
   {
      FindConvexHull(pp[0], fPoints, this);
   }
   if ( ! pp[1].empty())
   {
      fBreakIdx = fPoints.size();
      FindConvexHull(pp[1], fPoints, this);
   }
}
 
////////////////////////////////////////////////////////////////////////////////
/// Get state of fgDebugCornerPoints static.
 
Bool_t REveBoxProjected::GetDebugCornerPoints()
{
   return fDebugCornerPoints;
}
 
////////////////////////////////////////////////////////////////////////////////
/// Set state of fgDebugCornerPoints static.
/// When this is true, points will be drawn at the corners of
/// computed convex hull.
 
void REveBoxProjected::SetDebugCornerPoints(Bool_t d)
{
   fDebugCornerPoints = d;
}
 
////////////////////////////////////////////////////////////////////////////////
/// Crates 3D point array for rendering.
 
void REveBoxProjected::BuildRenderData()
{
   int N = fPoints.size();
 
   // makeBoxProjected draws the projected box as a 3D mesh
   // ignore REveBoxProjected render data if projected box is a line (N=2)
   if ( N < 3 ) return;
 
   fRenderData = std::make_unique<REveRenderData>("makeBoxProjected", N*3);
   for (auto &v : fPoints)
   {
      fRenderData->PushV(v.fX);
      fRenderData->PushV(v.fY);
      fRenderData->PushV(fDepth);
   }
}
 
////////////////////////////////////////////////////////////////////////////////
/// Fill core part of JSON representation.
 
Int_t REveBoxProjected::WriteCoreJson(nlohmann::json &j, Int_t rnr_offset)
{
   Int_t ret = REveShape::WriteCoreJson(j, rnr_offset);
 
   j["fBreakIdx"] = fBreakIdx;
 
   return ret;
}