qglviewerwidget.cc

penMesh is a generic and efficient data structure for representing and manipulating polygonal meshes

		     0.0f));
  }


	
  // rotate
  else if (_event->state() & LeftButton) 
  {
    if (last_point_ok_) 
    {
      if (newPoint_hitSphere = map_to_sphere(newPoint2D, newPoint3D)) 
      {
	Vec3f axis = last_point_3D_ % newPoint3D;
	float cos_angle = (last_point_3D_ | newPoint3D);
	if ( fabs(cos_angle) < 1.0 ) 
	{
	  float angle = 2.0 * acos( cos_angle ) * 180.0 / M_PI;
	  rotate( axis, angle );
	}
      }
    }
  }


  // remember this point
  last_point_2D_ = newPoint2D;
  last_point_3D_ = newPoint3D;
  last_point_ok_ = newPoint_hitSphere;

  // trigger redraw
  updateGL();
}


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


void
QGLViewerWidget::mouseReleaseEvent( QMouseEvent* _event )
{  
   last_point_ok_ = false;
}


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


void QGLViewerWidget::wheelEvent(QWheelEvent* _event)
{
  // Use the mouse wheel to zoom in/out

  float d = -(float)_event->delta() / 120.0 * 0.2 * radius_;
  translate(Vec3f(0.0, 0.0, d));
  updateGL();
  _event->accept();
}


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


void QGLViewerWidget::keyPressEvent( QKeyEvent* _event)
{
  switch( _event->key() )
  {
    case Key_C:
      if ( glIsEnabled( GL_CULL_FACE ) )
      {
	glDisable( GL_CULL_FACE );
	std::cout << "Back face culling: disabled\n";
      }
      else
      {
	glEnable( GL_CULL_FACE );
	std::cout << "Back face culling: enabled\n";
      }
      updateGL();
      break;

    case Key_I:
      std::cout << "Radius: " << radius_ << std::endl;
      std::cout << "Center: " << center_ << std::endl;
      break;

    case Key_Space:
    case Key_M:
    {
      double fps = performance();      
      std::cout << "fps: " 
#if defined(OM_CC_GCC) && (OM_CC_VERSION < 30000)
		<< std::setiosflags (std::ios::fixed)
#else
		<< std::setiosflags (std::ios_base::fixed)
#endif
		<< fps << std::endl;
    }
    break;
    
    case Key_Q:
    case Key_Escape:
      qApp->quit();      
  }
  _event->ignore();
}


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


void
QGLViewerWidget::translate( const Vec3f& _trans )
{
  // Translate the object by _trans
  // Update modelview_matrix_
  makeCurrent();
  glLoadIdentity();
  glTranslated( _trans[0], _trans[1], _trans[2] );
  glMultMatrixd( modelview_matrix_ );
  glGetDoublev( GL_MODELVIEW_MATRIX, modelview_matrix_);
}


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


void
QGLViewerWidget::rotate( const Vec3f& _axis, float _angle )
{
  // Rotate around center center_, axis _axis, by angle _angle
  // Update modelview_matrix_

  Vec3f t( modelview_matrix_[0]*center_[0] + 
	   modelview_matrix_[4]*center_[1] +
	   modelview_matrix_[8]*center_[2] + 
	   modelview_matrix_[12],
	   modelview_matrix_[1]*center_[0] + 
	   modelview_matrix_[5]*center_[1] +
	   modelview_matrix_[9]*center_[2] + 
	   modelview_matrix_[13],
	   modelview_matrix_[2]*center_[0] + 
	   modelview_matrix_[6]*center_[1] +
	   modelview_matrix_[10]*center_[2] + 
	   modelview_matrix_[14] );
  
  makeCurrent();
  glLoadIdentity();
  glTranslatef(t[0], t[1], t[2]);
  glRotated( _angle, _axis[0], _axis[1], _axis[2]);
  glTranslatef(-t[0], -t[1], -t[2]); 
  glMultMatrixd(modelview_matrix_);
  glGetDoublev(GL_MODELVIEW_MATRIX, modelview_matrix_);
}


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


bool
QGLViewerWidget::map_to_sphere( const QPoint& _v2D, Vec3f& _v3D )
{
  if ( (_v2D.x() >= 0) && (_v2D.x() <= width()) &&
       (_v2D.y() >= 0) && (_v2D.y() <= height()) ) 
  {
    double x  = (double)(_v2D.x() - 0.5*width())  / (double)width();
    double y  = (double)(0.5*height() - _v2D.y()) / (double)height();
    double sinx         = sin(M_PI * x * 0.5);
    double siny         = sin(M_PI * y * 0.5);
    double sinx2siny2   = sinx * sinx + siny * siny;
    
    _v3D[0] = sinx;
    _v3D[1] = siny;
    _v3D[2] = sinx2siny2 < 1.0 ? sqrt(1.0 - sinx2siny2) : 0.0;
    
    return true;
  }
  else return false;
}


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


void
QGLViewerWidget::update_projection_matrix()
{
  makeCurrent();
  glMatrixMode( GL_PROJECTION );
  glLoadIdentity();
  gluPerspective(45.0, (GLfloat) width() / (GLfloat) height(),
		 0.01*radius_, 100.0*radius_);
  glGetDoublev( GL_PROJECTION_MATRIX, projection_matrix_);
  glMatrixMode( GL_MODELVIEW );
}


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


void
QGLViewerWidget::view_all()
{  
  translate( Vec3f( -(modelview_matrix_[0]*center_[0] + 
		      modelview_matrix_[4]*center_[1] +
		      modelview_matrix_[8]*center_[2] + 
		      modelview_matrix_[12]),
		    -(modelview_matrix_[1]*center_[0] + 
		      modelview_matrix_[5]*center_[1] +
		      modelview_matrix_[9]*center_[2] + 
		      modelview_matrix_[13]),
		    -(modelview_matrix_[2]*center_[0] + 
		      modelview_matrix_[6]*center_[1] +
		      modelview_matrix_[10]*center_[2] + 
		      modelview_matrix_[14] +
		      3.0*radius_) ) );
}


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


void
QGLViewerWidget::set_scene_pos( const Vec3f& _cog, float _radius )
{
  center_ = _cog;
  radius_ = _radius;
  glFogf( GL_FOG_START,      _radius );
  glFogf( GL_FOG_END,    4.0*_radius );

  update_projection_matrix();
  view_all();
}


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


void 
QGLViewerWidget::add_draw_mode(const std::string& _s)
{
  ++n_draw_modes_;

  // insert in popup menu
  popup_menu_->insertItem(_s.c_str(), n_draw_modes_);

  // store draw mode
  draw_mode_names_.push_back(_s);
}


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


void
QGLViewerWidget::slotPopupMenu(int _id)
{
  // un-check all entries
  for (size_t i=1; i <= n_draw_modes_; ++i)
    popup_menu_->setItemChecked(i, false);

  // save draw mode
  draw_mode_ = _id;

  // check selected draw mode
  popup_menu_->setItemChecked(_id, true);
}


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


double 
QGLViewerWidget::performance()
{
  setCursor( waitCursor );

  double fps(0.0);

  makeCurrent();
  glMatrixMode(GL_MODELVIEW);
  glPushMatrix();

  OpenMesh::Utils::Timer timer;

  unsigned int  frames = 60;
  const float   angle  = 360.0/(float)frames;
  unsigned int  i;
  Vec3f         axis;

  glFinish();
  timer.start();

  for (i=0, axis=Vec3f(1,0,0); i<frames; ++i)
  { rotate(axis, angle); paintGL(); swapBuffers(); }
  for (i=0, axis=Vec3f(0,1,0); i<frames; ++i)
  { rotate(axis, angle); paintGL(); swapBuffers(); }
  for (i=0, axis=Vec3f(0,0,1); i<frames; ++i)
  { rotate(axis, angle); paintGL(); swapBuffers(); }

  glFinish();
  timer.stop();

  glPopMatrix();
  updateGL();

  fps = ( (3.0 * frames) / timer.seconds() );

  setCursor( pointingHandCursor );

  return fps;
}

//=============================================================================