C++ ON_NurbsSurface::CVSize方法代码示例

void nurbsfit::IncreaseDimension( const ON_NurbsSurface& src, ON_NurbsSurface& dest, int dim )
{
  dest.m_dim          = dim;
  dest.m_is_rat       = src.m_is_rat;
  dest.m_order[0]     = src.m_order[0];
  dest.m_order[1]     = src.m_order[1];
  dest.m_cv_count[0]  = src.m_cv_count[0];
  dest.m_cv_count[1]  = src.m_cv_count[1];
  dest.m_cv_stride[1] = dest.m_is_rat ? dest.m_dim+1 : dest.m_dim;
  dest.m_cv_stride[0] = dest.m_cv_count[1]*dest.m_cv_stride[1];
  if ( src.m_knot[0] )
  {
    // copy knot array
    dest.ReserveKnotCapacity( 0, dest.KnotCount(0) );
    memcpy( dest.m_knot[0], src.m_knot[0], dest.KnotCount(0)*sizeof(*dest.m_knot[0]) );
  }
  if ( src.m_knot[1] )
  {
    // copy knot array
    dest.ReserveKnotCapacity( 1, dest.KnotCount(1) );
    memcpy( dest.m_knot[1], src.m_knot[1], dest.KnotCount(1)*sizeof(*dest.m_knot[1]) );
  }
  if ( src.m_cv )
  {
    // copy cv array
    dest.ReserveCVCapacity( dest.m_cv_count[0]*dest.m_cv_count[1]*dest.m_cv_stride[1] );
    const int dst_cv_size = dest.CVSize()*sizeof(*dest.m_cv);
    const int src_stride[2] = {src.m_cv_stride[0],src.m_cv_stride[1]};
    if ( src_stride[0] == dest.m_cv_stride[0] && src_stride[1] == dest.m_cv_stride[1] )
    {
      memcpy( dest.m_cv, src.m_cv, dest.m_cv_count[0]*dest.m_cv_count[1]*dest.m_cv_stride[1]*sizeof(*dest.m_cv) );
    }
    else
    {
      const double *src_cv;
      double *dst_cv = dest.m_cv;
      int i, j;
      for ( i = 0; i < dest.m_cv_count[0]; i++ )
      {
        src_cv = src.CV(i,0);
        for ( j = 0; j < dest.m_cv_count[1]; j++ )
        {
          memcpy( dst_cv, src_cv, dst_cv_size );
          dst_cv += dest.m_cv_stride[1];
          src_cv += src_stride[1];
        }
      }
    }
  }
}

void ON_GL( const ON_NurbsSurface& s,
              GLUnurbsObj* nobj, // created with gluNewNurbsRenderer )
              GLenum type,       // = 0 (and type is automatically set)
              int bPermitKnotScaling,
              double* knot_scale0,
              double* knot_scale1
             )
{
  int i, j, k;

  // The "bPermitScaling" parameters to the ON_GL() call that
  // fills in the knot vectors is set to false because any
  // rescaling that is applied to a surface domain must also
  // be applied to parameter space trimming curve geometry.

  // GL "s" knots
  GLint sknot_count = s.KnotCount(0) + 2;
  GLfloat* sknot = (GLfloat*)onmalloc( sknot_count*sizeof(*sknot) );
  ON_GL( s.Order(0), s.CVCount(0), s.Knot(0), sknot, 
           bPermitKnotScaling, knot_scale0 );

  // GL "t" knots
  GLint tknot_count = s.KnotCount(1) + 2;
  GLfloat* tknot = (GLfloat*)onmalloc( tknot_count*sizeof(*tknot) );
  ON_GL( s.Order(1), s.CVCount(1), s.Knot(1), tknot,
           bPermitKnotScaling, knot_scale1 );

  // control vertices
  const int cv_size= s.CVSize();
  const int cv_count[2] = {s.CVCount(0), s.CVCount(1)};
  GLint s_stride = cv_size*cv_count[1];
  GLint t_stride = cv_size;
  GLfloat* ctlarray = (GLfloat*)onmalloc( s_stride*cv_count[0]*sizeof(*ctlarray) );
  for ( i = 0; i < cv_count[0]; i++ ) {
    for ( j = 0; j < cv_count[1]; j++ ) {
      const double*  cv = s.CV(i,j);
      GLfloat* gl_cv = ctlarray + s_stride*i + t_stride*j;
      for ( k = 0; k < cv_size; k++ ) {
        gl_cv[k] = (GLfloat)cv[k];
      }
    }
  }
  
  GLint sorder = s.Order(0);
  GLint torder = s.Order(1);

  if ( type == 0 ) {
    // set GL surface type for 3d CVs in homogeneous/euclidean form.
    type = ( s.IsRational() ) ? GL_MAP2_VERTEX_4 : GL_MAP2_VERTEX_3;
  }

  gluNurbsSurface (
    nobj,
    sknot_count,
    sknot,
    tknot_count,
    tknot,
    s_stride, 	
    t_stride, 	
    ctlarray, 	
    sorder, 	
    torder, 	
    type	
  );	

  onfree( ctlarray );
  onfree( tknot );
  onfree( sknot );
}