ExampleStencilBuffer.cpp

Example for usage Stencil buffer usage

, GLProjectionParametersPerspective,SceneOpenSceneGraph

Author

MIP

/* 
This file is part of the BIAS library (Basic ImageAlgorithmS).

Copyright (C) 2003, 2004    (see file CONTACTS for details)
  Multimediale Systeme der Informationsverarbeitung
  Institut fuer Informatik
  Christian-Albrechts-Universitaet Kiel


BIAS 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 2.1 of the License, or
(at your option) any later version.

BIAS 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 BIAS; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
*/

/**
   @example ExampleStencilBuffer.cpp
   @relates glfPBuffer, GLProjectionParametersPerspective,SceneOpenSceneGraph
   @brief Example for usage Stencil buffer usage
   @ingroup g_examples
   @ingroup g_glviewer
   @author MIP
*/

#include <iostream>
#include <Geometry/ProjectionParametersPerspective.hh>
#include <GLviewer/GLProjectionParametersPerspective.hh>
#include <GLviewer/Scenes/SceneOpenSceneGraph.hh>
#include <OpenGLFramework/RenderingContext/glfPBuffer.hh>
#include <Base/Image/ImageIO.hh>

using namespace std;
using namespace BIAS;

int main(int argc, char *argv[]) {
  
  
  glfPBuffer pbuffer;
  
  try {  

    glfRenderingContextConfig cfg;
    cfg.width         = 5;                  
    cfg.height        = 5;
    cfg.doubleBuffer  = 0;
    cfg.redSize       = 8;
    cfg.greenSize     = 8;
    cfg.blueSize      = 8;
    cfg.alphaSize     = 0;
    cfg.depthSize     = 24;
    cfg.stencilSize   = 0;

    // initialize context
    pbuffer.Init(cfg);
    
  } catch (glfException& e) {
    std::cout << "Error: " << e.GetMessageString() << std::endl;  
    pbuffer.Destroy();
    return -1;
  }

  
  //create synth projection parameters.
  ProjectionParametersPerspective ppp;
  ppp.SetC(Vector3<double>(0,0,0));
  ppp.SetR(RMatrix(Vector3<double>(1,0,0),0));
  ppp.SetSimplePerspective(M_PI/2,320,240);
  //some realistic distortion parameters

  ppp.SetUndistortion(-0.1614995748,0.1328560412,-6.499856681e-005,0.0005424174597);
  GLProjectionParametersPerspective glppp(ppp);
  glppp.SwitchToOffscreenRendering(true);
  glppp.IgnoreDistortion(false);
  glppp.SetSimplePerspectiveCam(90);
  //glppp.UseStencilBuffer(true);
  glppp.SetClearColor(Vector4<float>(1,0,1,0));
  vector<SceneBase*> scenes;
  SceneOpenSceneGraph sosg;
  sosg.Init();
//---- create a white quad
  osg::Group* group = new osg::Group;
  osg::Geometry* geom = new osg::Geometry;
  osg::Vec3Array* vertices = new osg::Vec3Array(4);
  osg::StateSet *stateset = group->getOrCreateStateSet();

  stateset->setMode(GL_CULL_FACE,osg::StateAttribute::OVERRIDE|osg::StateAttribute::OFF);
  (*vertices)[0] = osg::Vec3(-10, -10,10 );
  (*vertices)[1] = osg::Vec3(10,-10 ,10 );
  (*vertices)[2] = osg::Vec3(10,10 ,10 );
  (*vertices)[3] = osg::Vec3(-10,10 ,10 );
  geom->setVertexArray(vertices);
  osg::Vec4Array* colors = new osg::Vec4Array(1);
  (*colors)[0].set(1.0f, 1.0f, 1.0f, 1.0f);
  geom->setColorArray(colors);
  geom->setColorBinding(osg::Geometry::BIND_OVERALL);
  geom->addPrimitiveSet(new osg::DrawArrays(GL_QUADS,0,4));
  osg::Geode* geom_geode = new osg::Geode;
  geom_geode->addDrawable(geom);
  group->addChild(geom_geode);
  osg::ref_ptr<osg::Node> node = group;
//----
  sosg.AppendSubTree(node);
  scenes.push_back(&sosg);

  glppp.SetAutoReshapeBehaviour(GLProjectionParametersBase::AdaptToCroppedImage);
  glppp.SetIntrinsics(&ppp); //force initialization of distortion shader
  glppp.SetGLMatrices();    //seems a good idea!
  glppp.SetZClippingPlanes(1.0,20.0);
  int res=glppp.Draw(scenes); //let's render!
  res=glppp.Draw(scenes); //let's render!
  if(0!=res)
  {
    cerr<<"draw returned "<<res<<endl;
    return -1;
  }
  Image<float> depth;
  Image<unsigned char> color;
  glppp.GetImage(color);
  cout << "get depth" << endl;
  glppp.GetDepthMap(depth);
  if(depth.IsEmpty())
  {
    cerr<<"draw image empty. "<<endl;
    return -1;
  }
  ImageIO::Save("distortest.mip",depth);
  ImageIO::Save("distortest-c.mip",color);

  //if we have at the center of the depth image a depth close to 10
  float** pDat = depth.GetImageDataArray();
  float d = pDat[depth.GetHeight()/2][depth.GetWidth()/2];
  if((d<9.8f)||(d>14.0f))
  {
    cerr << "unexpected depth value - distortion failed." <<endl;
    return -1;
  }
  return 0;
}