/*=========================================================================

  Program:   Visualization Toolkit
  Module:    TestOSPRayLights.cxx

  Copyright (c) Ken Martin, Will Schroeder, Bill Lorensen
  All rights reserved.
  See Copyright.txt or http://www.kitware.com/Copyright.htm for details.

     This software is distributed WITHOUT ANY WARRANTY; without even
     the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
     PURPOSE.  See the above copyright notice for more information.

=========================================================================*/
// This test verifies that lighting works as expected with ospray.
// When advanced materials are exposed in ospray, it will also validate
// refractions and reflections
//
// The command line arguments are:
// -I        => run in interactive mode; unless this is used, the program will
//              not allow interaction and exit
//              In interactive mode it responds to the keys listed
//              vtkOSPRayTestInteractor.h

#include "vtkTestUtilities.h"

#include "vtkActor.h"
#include "vtkCamera.h"
#include "vtkLight.h"
#include "vtkOpenGLRenderer.h"
#include "vtkOSPRayPass.h"
#include "vtkOSPRayRendererNode.h"
#include "vtkPlaneSource.h"
#include "vtkPLYReader.h"
#include "vtkPolyDataMapper.h"
#include "vtkPolyDataNormals.h"
#include "vtkProperty.h"
#include "vtkRenderer.h"
#include "vtkRenderWindow.h"
#include "vtkRenderWindowInteractor.h"
#include "vtkSmartPointer.h"
#include "vtkSphereSource.h"

#include "vtkOSPRayTestInteractor.h"

int TestOSPRayLights(int argc, char* argv[])
{
  vtkSmartPointer<vtkRenderWindowInteractor> iren = vtkSmartPointer<vtkRenderWindowInteractor>::New();
  vtkSmartPointer<vtkRenderWindow> renWin = vtkSmartPointer<vtkRenderWindow>::New();
  iren->SetRenderWindow(renWin);
  vtkSmartPointer<vtkRenderer> renderer = vtkSmartPointer<vtkRenderer>::New();
  renderer->AutomaticLightCreationOff();
  renWin->AddRenderer(renderer);

  const char* fileName =
    vtkTestUtilities::ExpandDataFileName(argc, argv, "Data/bunny.ply");
  vtkSmartPointer<vtkPLYReader> polysource = vtkSmartPointer<vtkPLYReader>::New();
  polysource->SetFileName(fileName);

  //measure so we can place things sensibly
  polysource->Update();
  double bds[6];
  polysource->GetOutput()->GetBounds(bds);
  double x0 = bds[0]*2;
  double x1 = bds[1]*2;
  double y0 = bds[2];
  double y1 = bds[3]*2;
  double z0 = bds[4];
  double z1 = bds[5]*4;

  //TODO: ospray acts strangely without these such that Diff and Spec are not 0..255 instead of 0..1
  vtkSmartPointer<vtkPolyDataNormals> normals = vtkSmartPointer<vtkPolyDataNormals>::New();
  normals->SetInputConnection(polysource->GetOutputPort());

  vtkSmartPointer<vtkPolyDataMapper> mapper=vtkSmartPointer<vtkPolyDataMapper>::New();
  mapper->SetInputConnection(normals->GetOutputPort());
  vtkSmartPointer<vtkActor> actor=vtkSmartPointer<vtkActor>::New();
  actor->SetMapper(mapper);
  actor->GetProperty()->SetColor(1.0,1.0,1.0);
  actor->GetProperty()->SetAmbient(0.1);
  actor->GetProperty()->SetDiffuse(1);
  actor->GetProperty()->SetSpecularColor(1,1,1);
  actor->GetProperty()->SetSpecular(0.9);
  actor->GetProperty()->SetSpecularPower(500);
  renderer->AddActor(actor);

  vtkSmartPointer<vtkPlaneSource> backwall = vtkSmartPointer<vtkPlaneSource>::New();
  backwall->SetOrigin(x0,y0,z0);
  backwall->SetPoint1(x1,y0,z0);
  backwall->SetPoint2(x0,y1,z0);
  mapper=vtkSmartPointer<vtkPolyDataMapper>::New();
  mapper->SetInputConnection(backwall->GetOutputPort());
  actor=vtkSmartPointer<vtkActor>::New();
  actor->SetMapper(mapper);
  actor->GetProperty()->SetColor(1.0,1.0,1.0);
  actor->GetProperty()->SetAmbient(0.1);
  actor->GetProperty()->SetDiffuse(1);
  actor->GetProperty()->SetSpecular(0);
  renderer->AddActor(actor);

  vtkSmartPointer<vtkPlaneSource> floor = vtkSmartPointer<vtkPlaneSource>::New();
  floor->SetOrigin(x0,y0,z0);
  floor->SetPoint1(x0,y0,z1);
  floor->SetPoint2(x1,y0,z0);
  mapper=vtkSmartPointer<vtkPolyDataMapper>::New();
  mapper->SetInputConnection(floor->GetOutputPort());
  actor=vtkSmartPointer<vtkActor>::New();
  actor->GetProperty()->SetColor(1.0,1.0,1.0);
  actor->GetProperty()->SetAmbient(0.1);
  actor->GetProperty()->SetDiffuse(1);
  actor->GetProperty()->SetSpecular(0);
  actor->SetMapper(mapper);
  renderer->AddActor(actor);

  vtkSmartPointer<vtkPlaneSource> left = vtkSmartPointer<vtkPlaneSource>::New();
  left->SetOrigin(x0,y0,z0);
  left->SetPoint1(x0,y1,z0);
  left->SetPoint2(x0,y0,z1);
  mapper=vtkSmartPointer<vtkPolyDataMapper>::New();
  mapper->SetInputConnection(left->GetOutputPort());
  actor=vtkSmartPointer<vtkActor>::New();
  actor->GetProperty()->SetColor(1.0,1.0,1.0);
  actor->GetProperty()->SetAmbient(0.1);
  actor->GetProperty()->SetDiffuse(1);
  actor->GetProperty()->SetSpecular(0);
  actor->SetMapper(mapper);
  renderer->AddActor(actor);

  vtkSmartPointer<vtkSphereSource> magnifier = vtkSmartPointer<vtkSphereSource>::New();
  //TODO: use PathTracer_Dielectric material for this when available
  magnifier->SetCenter(x0+(x1-x0)*0.6, y0+(y1-y0)*0.2, z0+(z1-z0)*0.7);
  magnifier->SetRadius((x1-x0)*0.05);
  magnifier->SetPhiResolution(30);
  magnifier->SetThetaResolution(30);
  mapper=vtkSmartPointer<vtkPolyDataMapper>::New();
  mapper->SetInputConnection(magnifier->GetOutputPort());
  actor=vtkSmartPointer<vtkActor>::New();
  actor->GetProperty()->SetColor(1.0,1.0,1.0);
  actor->GetProperty()->SetAmbient(0.1);
  actor->GetProperty()->SetDiffuse(1);
  actor->GetProperty()->SetSpecular(0);
  actor->SetMapper(mapper);
  renderer->AddActor(actor);

  vtkSmartPointer<vtkSphereSource> discoball = vtkSmartPointer<vtkSphereSource>::New();
  //TODO: use PathTracer_Metal material for this when available
  discoball->SetCenter(x0+(x1-x0)*0.5, y0+(y1-y0)*0.85, z0+(z1-z0)*0.5);
  discoball->SetRadius((x1-x0)*0.1);
  discoball->SetPhiResolution(30);
  discoball->SetThetaResolution(30);
  mapper=vtkSmartPointer<vtkPolyDataMapper>::New();
  mapper->SetInputConnection(discoball->GetOutputPort());
  actor=vtkSmartPointer<vtkActor>::New();
  actor->GetProperty()->SetColor(1.0,1.0,1.0);
  actor->GetProperty()->SetAmbient(0.1);
  actor->GetProperty()->SetDiffuse(1);
  actor->GetProperty()->SetSpecular(0);
  actor->SetMapper(mapper);
  renderer->AddActor(actor);

  vtkSmartPointer<vtkLight> light = vtkSmartPointer<vtkLight>::New();
  //blue light casting shadows from infinity toward bottom left back corner
  light->PositionalOff();
  light->SetPosition(x0+(x1-x0)*1, y0+(y1-y0)*1, z0+(z1+z0)*1);
  light->SetFocalPoint(x0,           y0,           z0);
  light->SetLightTypeToSceneLight();
  light->SetColor(0.0,0.0,1.0);
  light->SetIntensity(0.3);
  light->SwitchOn();
  renderer->AddLight(light);

  light = vtkSmartPointer<vtkLight>::New();
  //red light casting shadows from top to bottom
  light->PositionalOn();
  double t = 1.8; //adjust t to see effect of positional
  light->SetPosition(  x0+(x1-x0)*0.5, y0+(y1-y0)*t, z0+(z1-z0)*0.5);
  light->SetFocalPoint(x0+(x1-x0)*0.5, y0+(y1-y0)*0, z0+(z1-z0)*0.5);
  light->SetLightTypeToSceneLight();
  light->SetColor(1.0,0.0,0.0);
  light->SetIntensity(0.3);
  light->SwitchOn();
  renderer->AddLight(light);

  light = vtkSmartPointer<vtkLight>::New();
  //green light following camera
  light->PositionalOn();
  light->SetLightTypeToHeadlight();
  light->SetColor(0.0,1.0,0.0);
  light->SetIntensity(0.3);
  light->SwitchOn();
  renderer->AddLight(light);

  renderer->SetBackground(0.0,0.0,0.0);
  renWin->SetSize(400,400);

  vtkSmartPointer<vtkOSPRayPass> ospray=vtkSmartPointer<vtkOSPRayPass>::New();
  renderer->SetPass(ospray);

  //increase image quality from default (otherwise subsampling artifacts)
  renWin->Render();
  renderer->UseShadowsOn();
  vtkOSPRayRendererNode::SetMaxFrames(5, renderer);
  vtkOSPRayRendererNode::SetSamplesPerPixel(4, renderer);

  vtkSmartPointer<vtkOSPRayTestInteractor> style =
    vtkSmartPointer<vtkOSPRayTestInteractor>::New();
  style->SetPipelineControlPoints(renderer, ospray, nullptr);
  iren->SetInteractorStyle(style);
  style->SetCurrentRenderer(renderer);

  iren->Start();

  return 0;
}
