LineNode.cc

/*===========================================================================*\
 *                                                                           *
 *                              OpenFlipper                                  *
 *      Copyright (C) 2001-2011 by Computer Graphics Group, RWTH Aachen      *
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 *  This file is part of OpenFlipper.                                        *
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/*===========================================================================*\
 *                                                                           *
 *   $Revision$                                                       *
 *   $Author$                                                      *
 *   $Date$                   *
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\*===========================================================================*/




//=============================================================================
//
//  CLASS LineNode - IMPLEMENTATION
//
//=============================================================================

//== INCLUDES =================================================================

#include "LineNode.hh"
#include "../GL/gl.hh"


//== NAMESPACES ===============================================================

namespace ACG {
namespace SceneGraph {

//== IMPLEMENTATION ==========================================================


void
LineNode::
boundingBox(Vec3d& _bbMin, Vec3d& _bbMax)
{
  ConstPointIter p_it=points_.begin(), p_end=points_.end();
  for (; p_it!=p_end; ++p_it)
  {
      _bbMax.maximize(*p_it);
      _bbMin.minimize(*p_it);
  }
}


//----------------------------------------------------------------------------


DrawModes::DrawMode
LineNode::
availableDrawModes() const
{
  return DrawModes::WIREFRAME;
}


//----------------------------------------------------------------------------

void
LineNode::
enter(GLState& _state , const DrawModes::DrawMode& _drawMode)
{
    MaterialNode::enter(_state, _drawMode);
    
    if (alwaysOnTop()) {
	//store current depth comparison function (needed for lasso selection)
	prev_depth_ = _state.depthFunc();
	
	//set depth function and change GLState accordingly
	_state.set_depthFunc(GL_ALWAYS);
    }
}

//----------------------------------------------------------------------------

void
LineNode::
draw(GLState& /* _state */ , const DrawModes::DrawMode& _drawMode)
{
  if (_drawMode & DrawModes::WIREFRAME)
  {
    ACG::GLState::disable(GL_LIGHTING);


   // if (line_mode_ == LineSegmentsMode)
   //   glBegin(GL_LINES);
   // else
   //   glBegin(GL_LINE_STRIP);


    // first check if (new standard) 4-channel colors are specified
    if ((line_mode_ == LineSegmentsMode) && (points_.size()/2 == colors4f_.size()) )
    {
      // enable blending of lines
      GLboolean blendb;
      glGetBooleanv( GL_BLEND, &blendb);
      glEnable(GL_BLEND);

      // blend func to blend alpha values of lines
      GLint sblendfunc;
      GLint dblendfunc;
      glGetIntegerv( GL_BLEND_SRC_ALPHA, &sblendfunc );
      glGetIntegerv( GL_BLEND_DST_ALPHA, &dblendfunc );
      glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);

      // blend ontop of prev. drawn mesh
      GLboolean depthmaskb;
      glGetBooleanv( GL_DEPTH_WRITEMASK, &depthmaskb);
      glDepthMask(GL_FALSE);

      glBegin(GL_LINES);

      ConstPointIter p_it=points_.begin(), p_end=points_.end();
      ConstColor4fIter c_it=colors4f_.begin();

      Color4f c(1.0f,1.0f,1.0f,1.0f);
      if(c_it != colors4f_.end()) {
        c = *c_it;
      }
      
      int cnt = 0;
      for (; p_it!=p_end; ++p_it)
      {
        if ((cnt > 0) && (cnt % 2 == 0) && (c_it+1) != colors4f_.end()) {
          ++c_it;
          c = *c_it;
        }
        
        glColor(c);
        glVertex(*p_it);

        ++cnt;
      }
      
      glEnd();

      // disable blending of lines
      if( blendb == GL_FALSE )
        glDisable(GL_BLEND);

      // reset blend func
      glBlendFunc( sblendfunc, dblendfunc );

      // enable depth mask
      if( depthmaskb == GL_TRUE )
        glDepthMask(GL_TRUE);

    }
    else if ((line_mode_ == LineSegmentsMode) && (points_.size()/2 == colors_.size()) )
    {
      glBegin(GL_LINES);
      ConstPointIter p_it=points_.begin(), p_end=points_.end();
      ConstColorIter c_it=colors_.begin();

      Color c((char)255, (char)255, (char)255);
      if(c_it != colors_.end()) {
        c = *c_it;
      }
      
      int cnt = 0;
      for (; p_it!=p_end; ++p_it)
      {
        if ((cnt > 0) && (cnt % 2 == 0) && (c_it+1) != colors_.end()) {
          ++c_it;
          c = *c_it;
        }
        
        glColor(c);
        glVertex(*p_it);

        ++cnt;
      }
      glEnd();
    }
    else
    {
      glBegin(GL_LINE_STRIP);
      ConstPointIter p_it=points_.begin(), p_end=points_.end();
      for (; p_it!=p_end; ++p_it)
        glVertex(*p_it);
      glEnd();
    }

    //glEnd();
  }
}
  
//----------------------------------------------------------------------------

void
LineNode::
leave(GLState& _state , const DrawModes::DrawMode& _drawMode)
{
  if (alwaysOnTop()) {
    //restore depth function and change GLState accordingly
    _state.set_depthFunc(prev_depth_);
  }

  MaterialNode::leave(_state, _drawMode);
}


//=============================================================================
} // namespace SceneGraph
} // namespace ACG
//=============================================================================