add vtk geant solid and scene

src/Vtk/HEP/Geant/vtkGeantSolid.cpp

@@ -0,0 +1,156 @@
+/*//////////////////////////////////////////////////////////////////////////////
+// CMT Cosmic Muon Tomography project //////////////////////////////////////////
+////////////////////////////////////////////////////////////////////////////////
+
+  Copyright (c) 2014, Universita' degli Studi di Padova, INFN sez. di Padova
+  All rights reserved
+
+  Authors: Andrea Rigoni Garola < andrea.rigoni@pd.infn.it >
+
+  ------------------------------------------------------------------
+  This library is free software;  you  can  redistribute  it  and/or
+  modify it  under the  terms  of  the  GNU  Lesser  General  Public
+  License as published  by  the  Free  Software  Foundation;  either
+  version 3.0 of the License, or (at your option) any later version.
+
+  This library is  distributed in  the hope that it will  be useful,
+  but  WITHOUT ANY WARRANTY;  without  even  the implied warranty of
+  MERCHANTABILITY  or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+  Lesser General Public License for more details.
+
+  You should have received a copy of  the GNU Lesser General  Public
+  License along with this library.
+
+//////////////////////////////////////////////////////////////////////////////*/
+
+#include "vtkGeantSolid.h"
+
+#include <vtkActor.h>
+#include <vtkPolyData.h>
+#include <vtkPoints.h>
+#include <vtkCellArray.h>
+#include <vtkPolyDataMapper.h>
+#include <vtkProperty.h>
+#include <vtkSmartPointer.h>
+#include <vtkTransform.h>
+#include <vtkMatrix4x4.h>
+
+#include <Geant4/G4VSolid.hh>
+#include <Geant4/G4Polyhedron.hh>
+#include <Geant4/G4VPhysicalVolume.hh>
+
+namespace uLib {
+namespace Vtk {
+
+vtkGeantSolid::vtkGeantSolid(Content *content)
+    : m_SolidActor(vtkActor::New()), m_Content(content) {
+  this->InstallPipe();
+  this->Update();
+}
+
+vtkGeantSolid::~vtkGeantSolid() {
+  m_SolidActor->Delete();
+}
+
+vtkPolyData *vtkGeantSolid::GetPolyData() const {
+  if (!m_SolidActor || !m_SolidActor->GetMapper())
+    return NULL;
+  return vtkPolyData::SafeDownCast(m_SolidActor->GetMapper()->GetInput());
+}
+
+void vtkGeantSolid::Update() {
+  if (!m_Content)
+    return;
+
+  G4VSolid *g4solid = m_Content->GetG4Solid();
+  if (!g4solid)
+    return;
+
+  // Get the polyhedron tessellation from Geant4
+  G4Polyhedron *polyhedron = g4solid->GetPolyhedron();
+  if (!polyhedron)
+    return;
+
+  vtkSmartPointer<vtkPoints> points = vtkSmartPointer<vtkPoints>::New();
+  vtkSmartPointer<vtkCellArray> polys = vtkSmartPointer<vtkCellArray>::New();
+
+  // Extract vertices
+  int nVertices = polyhedron->GetNoVertices();
+  for (int i = 1; i <= nVertices; ++i) {
+    G4Point3D vtx = polyhedron->GetVertex(i);
+    points->InsertNextPoint(vtx.x(), vtx.y(), vtx.z());
+  }
+
+  // Extract facets (polygons)
+  int nFacets = polyhedron->GetNoFacets();
+  for (int f = 1; f <= nFacets; ++f) {
+    G4int nEdges;
+    G4int iVertex[4]; // G4Polyhedron facets have at most 4 vertices
+    // GetNextFacet returns edges; for quads nEdges=4, for triangles nEdges=3
+    polyhedron->GetFacet(f, nEdges, iVertex);
+
+    vtkIdType ids[4];
+    for (int e = 0; e < nEdges; ++e) {
+      // G4Polyhedron vertices are 1-indexed; VTK expects 0-indexed
+      ids[e] = static_cast<vtkIdType>(std::abs(iVertex[e]) - 1);
+    }
+    polys->InsertNextCell(nEdges, ids);
+  }
+
+  vtkPolyData *polyData = GetPolyData();
+  if (polyData) {
+    polyData->SetPoints(points);
+    polyData->SetPolys(polys);
+    polyData->Modified();
+  }
+
+  // Apply the Geant4 transform (position/rotation) if placed
+  if (m_Content->GetPhysical()) {
+    auto *phys = m_Content->GetPhysical();
+    G4ThreeVector pos = phys->GetTranslation();
+    const G4RotationMatrix *rot = phys->GetRotation();
+
+    vtkSmartPointer<vtkTransform> transform = vtkSmartPointer<vtkTransform>::New();
+    transform->Identity();
+    transform->Translate(pos.x(), pos.y(), pos.z());
+
+    if (rot) {
+      // G4RotationMatrix stores the inverse of the rotation for placement
+      G4RotationMatrix invRot = rot->inverse();
+      double elements[16] = {
+        invRot.xx(), invRot.xy(), invRot.xz(), 0,
+        invRot.yx(), invRot.yy(), invRot.yz(), 0,
+        invRot.zx(), invRot.zy(), invRot.zz(), 0,
+        0, 0, 0, 1
+      };
+      vtkSmartPointer<vtkMatrix4x4> mat = vtkSmartPointer<vtkMatrix4x4>::New();
+      mat->DeepCopy(elements);
+      transform->Concatenate(mat);
+    }
+
+    m_SolidActor->SetUserTransform(transform);
+  }
+}
+
+void vtkGeantSolid::InstallPipe() {
+  vtkSmartPointer<vtkPolyData> polyData = vtkSmartPointer<vtkPolyData>::New();
+  vtkSmartPointer<vtkPolyDataMapper> mapper =
+      vtkSmartPointer<vtkPolyDataMapper>::New();
+  mapper->SetInputData(polyData);
+
+  m_SolidActor->SetMapper(mapper);
+
+  // Default look: semi-transparent blue surface
+  m_SolidActor->GetProperty()->SetColor(0.4, 0.6, 0.9);
+  m_SolidActor->GetProperty()->SetOpacity(0.3);
+  m_SolidActor->GetProperty()->SetAmbient(0.5);
+  m_SolidActor->GetProperty()->SetDiffuse(0.6);
+  m_SolidActor->GetProperty()->SetSpecular(0.2);
+  m_SolidActor->GetProperty()->SetEdgeVisibility(1);
+  m_SolidActor->GetProperty()->SetEdgeColor(0.2, 0.3, 0.5);
+
+  this->SetProp(m_SolidActor);
+}
+
+} // namespace Vtk
+} // namespace uLib