openscad/src/cgaladv_minkowski2.cc

138 lines
4.4 KiB
C++

/*
* OpenSCAD (www.openscad.org)
* Copyright (C) 2009-2011 Clifford Wolf <clifford@clifford.at> and
* Marius Kintel <marius@kintel.net>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* As a special exception, you have permission to link this program
* with the CGAL library and distribute executables, as long as you
* follow the requirements of the GNU GPL in regard to all of the
* software in the executable aside from CGAL.
*
* This program 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 General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
*/
#ifdef ENABLE_CGAL
#include "printutils.h"
#include "grid.h"
#include "cgal.h"
extern CGAL_Poly2 nef2p2(CGAL_Nef_polyhedron2 p);
//-----------------------------------------------------------------------------
// Pretty-print a CGAL polygon.
//
template<class Kernel, class Container>
void print_polygon (const CGAL::Polygon_2<Kernel, Container>& P)
{
typename CGAL::Polygon_2<Kernel, Container>::Vertex_const_iterator vit;
std::cout << "[ " << P.size() << " vertices:";
for (vit = P.vertices_begin(); vit != P.vertices_end(); ++vit)
std::cout << " (" << *vit << ')';
std::cout << " ]" << std::endl;
}
//-----------------------------------------------------------------------------
// Pretty-print a polygon with holes.
//
template<class Kernel, class Container>
void print_polygon_with_holes (const CGAL::Polygon_with_holes_2<Kernel, Container>& pwh) {
if (! pwh.is_unbounded()) {
std::cout << "{ Outer boundary = ";
print_polygon (pwh.outer_boundary());
} else
std::cout << "{ Unbounded polygon." << std::endl;
typename CGAL::Polygon_with_holes_2<Kernel,Container>::Hole_const_iterator hit;
unsigned int k = 1;
std::cout << " " << pwh.number_of_holes() << " holes:" << std::endl;
for (hit = pwh.holes_begin(); hit != pwh.holes_end(); ++hit, ++k) {
std::cout << " Hole #" << k << " = ";
print_polygon (*hit);
}
std::cout << " }" << std::endl;
return;
}
CGAL_Poly2 nef2p2(CGAL_Nef_polyhedron2 p)
{
std::list<CGAL_ExactKernel2::Point_2> points;
Grid2d<int> grid(GRID_COARSE);
typedef CGAL_Nef_polyhedron2::Explorer Explorer;
typedef Explorer::Face_const_iterator fci_t;
typedef Explorer::Halfedge_around_face_const_circulator heafcc_t;
Explorer E = p.explorer();
for (fci_t fit = E.faces_begin(), facesend = E.faces_end(); fit != facesend; ++fit)
{
if (!E.mark(fit)) {
continue;
}
//if (fit != E.faces_begin()) {
if (points.size() != 0) {
PRINT("WARNING: minkowski() and hull() is not implemented for 2d objects with holes!");
break;
}
heafcc_t fcirc(E.halfedge(fit)), fend(fcirc);
CGAL_For_all(fcirc, fend) {
if (E.is_standard(E.target(fcirc))) {
Explorer::Point ep = E.point(E.target(fcirc));
double x = to_double(ep.x()), y = to_double(ep.y());
grid.align(x, y);
points.push_back(CGAL_ExactKernel2::Point_2(x, y));
}
}
}
return CGAL_Poly2(points.begin(), points.end());
}
static CGAL_Nef_polyhedron2 p2nef2(CGAL_Poly2 p2) {
std::list<CGAL_Nef_polyhedron2::Point> points;
for (size_t j = 0; j < p2.size(); j++) {
double x = to_double(p2[j].x());
double y = to_double(p2[j].y());
CGAL_Nef_polyhedron2::Point p = CGAL_Nef_polyhedron2::Point(x, y);
points.push_back(p);
}
return CGAL_Nef_polyhedron2(points.begin(), points.end(), CGAL_Nef_polyhedron2::INCLUDED);
}
CGAL_Nef_polyhedron2 minkowski2(const CGAL_Nef_polyhedron2 &a, const CGAL_Nef_polyhedron2 &b)
{
CGAL_Poly2 ap = nef2p2(a), bp = nef2p2(b);
if (ap.size() == 0) {
PRINT("WARNING: minkowski() could not get any points from object 1!");
return CGAL_Nef_polyhedron2();
} else if (bp.size() == 0) {
PRINT("WARNING: minkowski() could not get any points from object 2!");
return CGAL_Nef_polyhedron2();
} else {
CGAL_Poly2h x = minkowski_sum_2(ap, bp);
// Make a CGAL_Nef_polyhedron2 out of just the boundary for starters
return p2nef2(x.outer_boundary());
}
}
#endif