vcglib/apps/metro/min_dist_point.h

/*#***************************************************************************
 * MinDistPoint.h                                                     o o    *
 *                                                                  o     o  *
 * Visual Computing Group                                           _  O  _  *
 * IEI Institute, CNUCE Institute, CNR Pisa                          \/)\/   *
 *                                                                  /\/|     *
 * Copyright(C) 1999 by Paolo Cignoni, Paolo Pingi, Claudio Rocchini   |     *
 * All rights reserved.                                                \     *
 *                                                                           *
 * Permission  to use, copy, modify, distribute  and sell this  software and *
 * its documentation for any purpose is hereby granted without fee, provided *
 * that  the above copyright notice appear  in all copies and that both that *
 * copyright   notice  and  this  permission  notice  appear  in  supporting *
 * documentation. the author makes  no representations about the suitability *
 * of this software for any purpose. It is provided  "as is" without express *
 * or implied warranty.                                                      *
 *                                                                           *
 * NOTE THAT THIS FILE SHOULD NOT DIRECTL BE INCLUDED                        *
 * It is automatically included by Mesh.h                                    *
 *                                                                           *
 ***************************************************************************#*/
/*#**************************************************************************
  History

 2000	Nov 06 First Working release (pc)
          08 Aggiunto if(gr.bbox.IsIn(p)) per evitare piantamenti se si chiede
						 un punto fuori.
						 Tolto un Normalize inutile
 2001 May 17 Aggiunta versione della Mindistpoint che da anche le coord 
						 baricentriche del punto trovato (pc); aggiunto wrapper per la vecchia 
						 versione.
			Dec 10 Corretto prodotto scalare vettore nell'ordine giusto in un paio di posti
 2002 Mar 29 Templatata anche in funzione del tipo scalare. (pc)
      Oct 24 Corretti warning (unsigned mismatch) del vc7, 
 2003 Apr 15 Corretti mismatch iterator / pointer 
      Jun 08 Aggiornato UGridLink -> UGrid::Link
 2004 Gen 09 Aggiunte le inclusioni a Point3[4].h
 2004 Gen 19 Corretto qualche ->Normal() in ->cN()
****************************************************************************/
#ifndef __VCG_MINDISTPOINT
#define __VCG_MINDISTPOINT
#include <math.h>

#include <vcg/space/point3.h>
#include <vcg/space/box3.h>
#include <vcg/space/point4.h>
#include <vcg/math/base.h>
#include <vcg/space/index/grid_static_ptr.h>


using namespace vcg;


/*
aka MetroCore
data una mesh m e una ug sulle sue facce trova il punto di m piu' vicino ad
un punto dato.
*/

// input: mesh, punto, griglia, distanza limite
// output: normale alla faccia e punto piu' vicino su di essa

// Nota che il parametro template GRID non ci dovrebbe essere, visto che deve essere 
// UGrid<MESH::FaceContainer >, ma non sono riuscito a definirlo implicitamente 

template <class MESH, class GRID, class SCALAR>
void MinDistPoint( MESH & mesh, const Point3<SCALAR> & p, GRID & gr, SCALAR & mdist, 
									Point3<SCALAR> & normf, Point3<SCALAR> & bestq, typename MESH::FaceType * &f, Point3<SCALAR> &ip)
{
	typedef SCALAR scalar;
  typedef Point3<scalar> Point3x;
  typedef Box3<SCALAR> Box3x;
	
	if(!gr.bbox.IsIn(p)) return;
	typedef typename GridStaticPtr<typename MESH::FaceContainer>::Link A2UGridLink;
  scalar ax = p[0] - gr.bbox.min[0];	// Real coodinate of point refer to
  scalar ay = p[1] - gr.bbox.min[1];	
  scalar az = p[2] - gr.bbox.min[2];

  int gx = int( ax/gr.voxel[0] );		// Integer coordinate of the point 
  int gy = int( ay/gr.voxel[1] );		// voxel
  int gz = int( az/gr.voxel[2] );

  scalar vx = gr.bbox.min[0]+gx*gr.voxel[0];	// Real world coordinate of the Voxel
  scalar vy = gr.bbox.min[1]+gy*gr.voxel[1];	// origin
	scalar vz = gr.bbox.min[2]+gz*gr.voxel[2];

	scalar dx = math::Min(p[0] - vx, vx+gr.voxel[0]-p[0]);  // Dist from the voxel
  scalar dy = math::Min(p[1] - vy, vy+gr.voxel[1]-p[1]);
  scalar dz = math::Min(p[2] - vz, vz+gr.voxel[2]-p[2]);

	scalar vdist,vstep;

	if(dx<dy && dx<dz)
	{
	    vdist = dx;
	    vstep = gr.voxel[0];
	}
	else if(dy<dz)
	{
	    vdist = dy;
	    vstep = gr.voxel[1];
	}
	else
	{
	    vdist = dz;
	    vstep = gr.voxel[2];
	}

	//scalar error = gr.bbox.SquaredDiag();
	//scalar error = gr.bbox.Diag();
	scalar error = mdist;
	Point3x q;
	typename MESH::FaceIterator bestf = (typename MESH::FaceIterator)0;

  mesh.UnMarkAll();

	int mxsd = gr.siz[0];
	if(mxsd<gr.siz[1]) mxsd = gr.siz[1];
	if(mxsd<gr.siz[2]) mxsd = gr.siz[2];
	for(int s=0;s<mxsd;++s)
	{
		if(s==0)
		{

			A2UGridLink *first, *last, *l;
			gr.Grid( gx, gy, gz, first, last );
			for(l=first;l!=last;++l)

				if( ! mesh.IsMarked( &*(l->Elem())) )
			{
				if( Dist((*(l->Elem())), p, error, q) )
				{
					bestq = q;
					bestf = l->Elem();
					typename MESH::ScalarType alfa=1, beta=1, gamma=1;
					
					//bestf->InterpolationParameters(q, alfa, beta);
					//calcolo normale con interpolazione trilineare
					/*normf = (1-(alfa+beta))*(bestf->V(0)->Normal())+
							(alfa*(bestf->V(1)->Normal()))+
							(beta*(bestf->V(2)->Normal()));*/
					bestf->InterpolationParameters(q, alfa, beta, gamma);
					normf =       (bestf->V(0)->cN())*alfa+
							          (bestf->V(1)->cN())*beta+
							          (bestf->V(2)->cN())*gamma;
					normf.Normalize();
					ip[0]=alfa;ip[1]=beta;ip[2]=gamma;

				}

				mesh.Mark( &*(l->Elem()) );
			}
		}
		else
		{
			for(int ix=gx-s;ix<=gx+s;++ix)
				if( ix>=0 && ix<gr.siz[0] )
				{
					for(int iy=gy-s;iy<=gy+s;++iy)
						if( iy>=0 && iy<gr.siz[1] )
						{
							int sz = ( ix==gx-s || ix==gx+s ||
								       iy==gy-s || iy==gy+s   )?1:2*s;
							for(int iz=gz-s;iz<=gz+s;iz+=sz)
								if( iz>=0 && iz<gr.siz[2] )
								{
									A2UGridLink *first, *last, *l;
									gr.Grid( ix, iy, iz, first, last );
									for(l=first;l!=last;++l)
									if( ! mesh.IsMarked( &*(l->Elem())) )
									{
										if( Dist((*(l->Elem())),  p, error, q) )
										{
											bestq = q;
											bestf = l->Elem();
											typename MESH::ScalarType alfa, beta, gamma;
											//bestf->InterpolationParameters(q, alfa, beta);
											//calcolo normale con interpolazione trilineare
											bestf->InterpolationParameters(q, alfa, beta, gamma);
											normf =  (bestf->V(0)->cN())*alfa+
											         (bestf->V(1)->cN())*beta+
													     (bestf->V(2)->cN())*gamma ;
											ip[0]=alfa;ip[1]=beta;ip[2]=gamma;
											//normf.Normalize(); inutile si assume le normali ai vertici benfatte
										}
										mesh.Mark(&*l->Elem());
									}
								}
						}
				}
		}

		if( fabs(error)<vdist )
			break;
		vdist += vstep;
	}
	f=&*bestf;
	mdist = scalar(fabs(error));
}

template <class MESH, class GRID, class SCALAR>
void MinDistPoint( MESH & mesh, const Point3<SCALAR> & p, GRID & gr, SCALAR & mdist, 
									Point3<SCALAR> & normf, Point3<SCALAR> & bestq, typename MESH::face_type * &f)
{
	Point3<SCALAR> ip;
	MinDistPoint(mesh,p,gr,mdist,normf,bestq,f,ip);
}
#endif