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#include <boost/foreach.hpp>
#include <boost/algorithm/string.hpp>
#include <sstream>
#include <iostream>
#include <locale.h>
#include "cgalutils.h"
// Nef polyhedron are using CGAL_Kernel3 (Cartesian<Gmpq>)
// Triangulation will use Epick
static void export_stl(const Polygons &triangles, std::ostream &output)
{
setlocale(LC_NUMERIC, "C"); // Ensure radix is . (not ,) in output
output << "solid OpenSCAD_Model\n";
BOOST_FOREACH(const Polygon &p, triangles) {
assert(p.size() == 3); // STL only allows triangles
std::stringstream stream;
stream << p[0][0] << " " << p[0][1] << " " << p[0][2];
std::string vs1 = stream.str();
stream.str("");
stream << p[1][0] << " " << p[1][1] << " " << p[1][2];
std::string vs2 = stream.str();
stream.str("");
stream << p[2][0] << " " << p[2][1] << " " << p[2][2];
std::string vs3 = stream.str();
if (vs1 != vs2 && vs1 != vs3 && vs2 != vs3) {
// The above condition ensures that there are 3 distinct vertices, but
// they may be collinear. If they are, the unit normal is meaningless
// so the default value of "1 0 0" can be used. If the vertices are not
// collinear then the unit normal must be calculated from the
// components.
Vector3d normal = (p[1] - p[0]).cross(p[2] - p[0]);
normal.normalize();
output << " facet normal " << normal[0] << " " << normal[1] << " " << normal[2] << "\n";
output << " outer loop\n";
BOOST_FOREACH(const Vector3d &v, p) {
output << " vertex " << v[0] << " " << v[1] << " " << v[2] << "\n";
}
output << " endloop\n";
output << " endfacet\n";
}
}
output << "endsolid OpenSCAD_Model\n";
setlocale(LC_NUMERIC, ""); // Set default locale
}
/*!
file format:
1. polygon coordinates (x,y,z) are comma separated (+/- spaces) and
each coordinate is on a separate line
2. each polygon is separated by one or more blank lines
*/
bool import_polygon(PolyholeK &polyhole, const std::string &filename)
{
std::ifstream ifs(filename.c_str());
if (!ifs) return false;
std::string line;
PolygonK polygon;
while (std::getline(ifs, line)) {
std::stringstream ss(line);
double X = 0.0, Y = 0.0, Z = 0.0;
if (!(ss >> X)) {
//ie blank lines => flag start of next polygon
if (polygon.size() > 0) polyhole.push_back(polygon);
polygon.clear();
continue;
}
char c = ss.peek();
while (c == ' ') {ss.read(&c, 1); c = ss.peek();} //gobble spaces before comma
if (c == ',') {ss.read(&c, 1); c = ss.peek();} //gobble comma
while (c == ' ') {ss.read(&c, 1); c = ss.peek();} //gobble spaces after comma
if (!(ss >> Y)) {
std::cerr << "Y error\n";
return false;
}
c = ss.peek();
while (c == ' ') {ss.read(&c, 1); c = ss.peek();} //gobble spaces before comma
if (c == ',') {ss.read(&c, 1); c = ss.peek();} //gobble comma
while (c == ' ') {ss.read(&c, 1); c = ss.peek();} //gobble spaces after comma
if (!(ss >> Z)) {
std::cerr << "Z error\n";
return false;
}
polygon.push_back(Vertex3K(X, Y, Z));
}
if (polygon.size() > 0) polyhole.push_back(polygon);
ifs.close();
return true;
}
//------------------------------------------------------------------------------
int main(int argc, char *argv[])
{
PolyholeK polyhole;
K::Vector_3 *normal = NULL;
if (argc >= 2) {
if (!import_polygon(polyhole, argv[1])) {
std::cerr << "Error importing polygon" << std::endl;
exit(1);
}
std::cerr << "Imported " << polyhole.size() << " polygons" << std::endl;
if (argc == 3) {
std::vector<std::string> strs;
std::vector<double> normalvec;
std::string arg(argv[2]);
boost::split(strs, arg, boost::is_any_of(","));
assert(strs.size() == 3);
BOOST_FOREACH(const std::string &s, strs) normalvec.push_back(boost::lexical_cast<double>(s));
normal = new K::Vector_3(normalvec[0], normalvec[1], normalvec[2]);
}
}
else {
//construct two non-intersecting nested polygons
PolygonK polygon1;
polygon1.push_back(Vertex3K(0,0,0));
polygon1.push_back(Vertex3K(2,0,0));
polygon1.push_back(Vertex3K(2,2,0));
polygon1.push_back(Vertex3K(0,2,0));
PolygonK polygon2;
polygon2.push_back(Vertex3K(0.5,0.5,0));
polygon2.push_back(Vertex3K(1.5,0.5,0));
polygon2.push_back(Vertex3K(1.5,1.5,0));
polygon2.push_back(Vertex3K(0.5,1.5,0));
polyhole.push_back(polygon1);
polyhole.push_back(polygon2);
}
Polygons triangles;
bool ok = CGALUtils::tessellatePolygonWithHoles(polyhole, triangles, normal);
std::cerr << "Tessellated into " << triangles.size() << " triangles" << std::endl;
export_stl(triangles, std::cout);
}
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