CGAL_Nef_polyhedron.cc

#include "CGAL_Nef_polyhedron.h"
#include "cgal.h"
#include "cgalutils.h"
#include "printutils.h"
#include "polyset.h"
#include "svg.h"

CGAL_Nef_polyhedron::CGAL_Nef_polyhedron(const CGAL_Nef_polyhedron3 *p)
{
	if (p) p3.reset(p);
}

// Copy constructor only performs shallow copies, so all modifying functions
// must reset p3 with a new CGAL_Nef_polyhedron3 object, to prevent cache corruption.
// This is also partly enforced by p3 pointing to a const object.
CGAL_Nef_polyhedron::CGAL_Nef_polyhedron(const CGAL_Nef_polyhedron &src)
{
	if (src.p3) this->p3 = src.p3;
}

CGAL_Nef_polyhedron CGAL_Nef_polyhedron::operator+(const CGAL_Nef_polyhedron &other) const
{
	return CGAL_Nef_polyhedron(new CGAL_Nef_polyhedron3((*this->p3) + (*other.p3)));
}

CGAL_Nef_polyhedron& CGAL_Nef_polyhedron::operator+=(const CGAL_Nef_polyhedron &other)
{
	this->p3.reset(new CGAL_Nef_polyhedron3((*this->p3) + (*other.p3)));
	return *this;
}

CGAL_Nef_polyhedron& CGAL_Nef_polyhedron::operator*=(const CGAL_Nef_polyhedron &other)
{
	this->p3.reset(new CGAL_Nef_polyhedron3((*this->p3) * (*other.p3)));
	return *this;
}

CGAL_Nef_polyhedron& CGAL_Nef_polyhedron::operator-=(const CGAL_Nef_polyhedron &other)
{
	this->p3.reset(new CGAL_Nef_polyhedron3((*this->p3) - (*other.p3)));
	return *this;
}

// Note: this is only the fallback method in case of failure in CGALUtils::applyMinkowski (see: cgalutils-applyops.cc)
CGAL_Nef_polyhedron &CGAL_Nef_polyhedron::minkowski(const CGAL_Nef_polyhedron &other)
{
	// It is required to construct copies of our const input operands here.
	// "Postcondition: If either of the input polyhedra is non-convex, it is modified during the computation,
	//  i.e., it is decomposed into convex pieces."
	// from https://doc.cgal.org/latest/Minkowski_sum_3/group__PkgMinkowskiSum3Ref.html
	CGAL_Nef_polyhedron3 op1(*this->p3);
	CGAL_Nef_polyhedron3 op2(*other.p3);
	this->p3.reset(new CGAL_Nef_polyhedron3(CGAL::minkowski_sum_3(op1, op2)));
	return *this;
}

size_t CGAL_Nef_polyhedron::memsize() const
{
	if (this->isEmpty()) return 0;

	auto memsize = sizeof(CGAL_Nef_polyhedron);
	memsize += const_cast<CGAL_Nef_polyhedron3&>(*this->p3).bytes();
	return memsize;
}

bool CGAL_Nef_polyhedron::isEmpty() const
{
	return !this->p3 || this->p3->is_empty();
}

BoundingBox CGAL_Nef_polyhedron::getBoundingBox() const
{
	if (isEmpty()) {
		return BoundingBox();
	}
	auto bb = CGALUtils::boundingBox(*this->p3).bbox();

	BoundingBox result;
	result.extend(Vector3d(bb.xmin(), bb.ymin(), bb.zmin()));
	result.extend(Vector3d(bb.xmax(), bb.ymax(), bb.zmax()));
	return result;
}

void CGAL_Nef_polyhedron::resize(const Vector3d &newsize,
                                 const Eigen::Matrix<bool,3,1> &autosize)
{
	// Based on resize() in Giles Bathgate's RapCAD (but not exactly)
	if (this->isEmpty()) return;

	auto bb = CGALUtils::boundingBox(*this->p3);

	std::vector<NT3> scale, bbox_size;
	for (unsigned int i=0; i<3; ++i) {
		scale.push_back(NT3(1));
		bbox_size.push_back(bb.max_coord(i) - bb.min_coord(i));
	}
	int newsizemax_index = 0;
	for (unsigned int i=0; i<this->getDimension(); ++i) {
		if (newsize[i]) {
			if (bbox_size[i] == NT3(0)) {
				LOG(message_group::Warning,Location::NONE,"","Resize in direction normal to flat object is not implemented");
				return;
			}
			else {
				scale[i] = NT3(newsize[i]) / bbox_size[i];
			}
			if (newsize[i] > newsize[newsizemax_index]) newsizemax_index = i;
		}
	}

	auto autoscale = NT3(1);
	if (newsize[newsizemax_index] != 0) {
		autoscale = NT3(newsize[newsizemax_index]) / bbox_size[newsizemax_index];
	}
	for (unsigned int i=0; i<this->getDimension(); ++i) {
		if (autosize[i] && newsize[i]==0) scale[i] = autoscale;
	}

	Eigen::Matrix4d t;
	t << CGAL::to_double(scale[0]),           0,        0,        0,
	     0,        CGAL::to_double(scale[1]),           0,        0,
	     0,        0,        CGAL::to_double(scale[2]),           0,
	     0,        0,        0,                                   1;

	this->transform(Transform3d(t));
}

std::string CGAL_Nef_polyhedron::dump() const
{
	return OpenSCAD::dump_svg( *this->p3 );
}

void CGAL_Nef_polyhedron::transform( const Transform3d &matrix )
{
	if (!this->isEmpty()) {
		if (matrix.matrix().determinant() == 0) {
			LOG(message_group::Warning,Location::NONE,"","Scaling a 3D object with 0 - removing object");
			this->reset();
		}
		else {
			auto N = new CGAL_Nef_polyhedron3(*this->p3);
			CGAL_Aff_transformation t(
				matrix(0,0), matrix(0,1), matrix(0,2), matrix(0,3),
				matrix(1,0), matrix(1,1), matrix(1,2), matrix(1,3),
				matrix(2,0), matrix(2,1), matrix(2,2), matrix(2,3), matrix(3,3));
			N->transform(t);
			this->p3.reset(N);
		}
	}
}