FreeCAD/src/Mod/Path/libarea/AreaClipper.cpp

502 lines
13 KiB
C++

// AreaClipper.cpp
// implements CArea methods using Angus Johnson's "Clipper"
#include "Area.h"
#include "clipper.hpp"
using namespace ClipperLib;
#define TPolygon Path
#define TPolyPolygon Paths
bool CArea::HolesLinked(){ return false; }
//static const double PI = 3.1415926535897932;
static double Clipper4Factor = 10000.0;
class DoubleAreaPoint
{
public:
double X, Y;
DoubleAreaPoint(double x, double y){X = x; Y = y;}
DoubleAreaPoint(const IntPoint& p){X = (double)(p.X) / Clipper4Factor; Y = (double)(p.Y) / Clipper4Factor;}
IntPoint int_point(){return IntPoint((long64)(X * Clipper4Factor), (long64)(Y * Clipper4Factor));}
};
static std::list<DoubleAreaPoint> pts_for_AddVertex;
static void AddPoint(const DoubleAreaPoint& p)
{
pts_for_AddVertex.push_back(p);
}
static void AddVertex(const CVertex& vertex, const CVertex* prev_vertex)
{
if(vertex.m_type == 0 || prev_vertex == NULL)
{
AddPoint(DoubleAreaPoint(vertex.m_p.x * CArea::m_units, vertex.m_p.y * CArea::m_units));
}
else
{
if(vertex.m_p != prev_vertex->m_p)
{
double phi,dphi,dx,dy;
int Segments;
int i;
double ang1,ang2,phit;
dx = (prev_vertex->m_p.x - vertex.m_c.x) * CArea::m_units;
dy = (prev_vertex->m_p.y - vertex.m_c.y) * CArea::m_units;
ang1=atan2(dy,dx);
if (ang1<0) ang1+=2.0*PI;
dx = (vertex.m_p.x - vertex.m_c.x) * CArea::m_units;
dy = (vertex.m_p.y - vertex.m_c.y) * CArea::m_units;
ang2=atan2(dy,dx);
if (ang2<0) ang2+=2.0*PI;
if (vertex.m_type == -1)
{ //clockwise
if (ang2 > ang1)
phit=2.0*PI-ang2+ ang1;
else
phit=ang1-ang2;
}
else
{ //counter_clockwise
if (ang1 > ang2)
phit=-(2.0*PI-ang1+ ang2);
else
phit=-(ang2-ang1);
}
//what is the delta phi to get an accurancy of aber
double radius = sqrt(dx*dx + dy*dy);
dphi=2*acos((radius-CArea::m_accuracy)/radius);
//set the number of segments
if (phit > 0)
Segments=(int)ceil(phit/dphi);
else
Segments=(int)ceil(-phit/dphi);
if (Segments < 1)
Segments=1;
if (Segments > 100)
Segments=100;
dphi=phit/(Segments);
double px = prev_vertex->m_p.x * CArea::m_units;
double py = prev_vertex->m_p.y * CArea::m_units;
for (i=1; i<=Segments; i++)
{
dx = px - vertex.m_c.x * CArea::m_units;
dy = py - vertex.m_c.y * CArea::m_units;
phi=atan2(dy,dx);
double nx = vertex.m_c.x * CArea::m_units + radius * cos(phi-dphi);
double ny = vertex.m_c.y * CArea::m_units + radius * sin(phi-dphi);
AddPoint(DoubleAreaPoint(nx, ny));
px = nx;
py = ny;
}
}
}
}
static void MakeLoop(const DoubleAreaPoint &pt0, const DoubleAreaPoint &pt1, const DoubleAreaPoint &pt2, double radius)
{
Point p0(pt0.X, pt0.Y);
Point p1(pt1.X, pt1.Y);
Point p2(pt2.X, pt2.Y);
Point forward0 = p1 - p0;
Point right0(forward0.y, -forward0.x);
right0.normalize();
Point forward1 = p2 - p1;
Point right1(forward1.y, -forward1.x);
right1.normalize();
int arc_dir = (radius > 0) ? 1 : -1;
CVertex v0(0, p1 + right0 * radius, Point(0, 0));
CVertex v1(arc_dir, p1 + right1 * radius, p1);
CVertex v2(0, p2 + right1 * radius, Point(0, 0));
double save_units = CArea::m_units;
CArea::m_units = 1.0;
AddVertex(v1, &v0);
AddVertex(v2, &v1);
CArea::m_units = save_units;
}
static void OffsetWithLoops(const TPolyPolygon &pp, TPolyPolygon &pp_new, double inwards_value)
{
Clipper c;
bool inwards = (inwards_value > 0);
bool reverse = false;
double radius = -fabs(inwards_value);
if(inwards)
{
// add a large square on the outside, to be removed later
TPolygon p;
p.push_back(DoubleAreaPoint(-10000.0, -10000.0).int_point());
p.push_back(DoubleAreaPoint(-10000.0, 10000.0).int_point());
p.push_back(DoubleAreaPoint(10000.0, 10000.0).int_point());
p.push_back(DoubleAreaPoint(10000.0, -10000.0).int_point());
c.AddPath(p, ptSubject, true);
}
else
{
reverse = true;
}
for(unsigned int i = 0; i < pp.size(); i++)
{
const TPolygon& p = pp[i];
pts_for_AddVertex.clear();
if(p.size() > 2)
{
if(reverse)
{
for(std::size_t j = p.size()-1; j > 1; j--)MakeLoop(p[j], p[j-1], p[j-2], radius);
MakeLoop(p[1], p[0], p[p.size()-1], radius);
MakeLoop(p[0], p[p.size()-1], p[p.size()-2], radius);
}
else
{
MakeLoop(p[p.size()-2], p[p.size()-1], p[0], radius);
MakeLoop(p[p.size()-1], p[0], p[1], radius);
for(std::size_t j = 2; j < p.size(); j++)MakeLoop(p[j-2], p[j-1], p[j], radius);
}
TPolygon loopy_polygon;
loopy_polygon.reserve(pts_for_AddVertex.size());
for(std::list<DoubleAreaPoint>::iterator It = pts_for_AddVertex.begin(); It != pts_for_AddVertex.end(); It++)
{
loopy_polygon.push_back(It->int_point());
}
c.AddPath(loopy_polygon, ptSubject, true);
pts_for_AddVertex.clear();
}
}
//c.ForceOrientation(false);
c.Execute(ctUnion, pp_new, pftNonZero, pftNonZero);
if(inwards)
{
// remove the large square
if(pp_new.size() > 0)
{
pp_new.erase(pp_new.begin());
}
}
else
{
// reverse all the resulting polygons
TPolyPolygon copy = pp_new;
pp_new.clear();
pp_new.resize(copy.size());
for(unsigned int i = 0; i < copy.size(); i++)
{
const TPolygon& p = copy[i];
TPolygon p_new;
p_new.resize(p.size());
std::size_t size_minus_one = p.size() - 1;
for(std::size_t j = 0; j < p.size(); j++)p_new[j] = p[size_minus_one - j];
pp_new[i] = p_new;
}
}
}
static void MakeObround(const Point &pt0, const CVertex &vt1, double radius)
{
Span span(pt0, vt1);
Point forward0 = span.GetVector(0.0);
Point forward1 = span.GetVector(1.0);
Point right0(forward0.y, -forward0.x);
Point right1(forward1.y, -forward1.x);
right0.normalize();
right1.normalize();
CVertex v0(pt0 + right0 * radius);
CVertex v1(vt1.m_type, vt1.m_p + right1 * radius, vt1.m_c);
CVertex v2(1, vt1.m_p + right1 * -radius, vt1.m_p);
CVertex v3(-vt1.m_type, pt0 + right0 * -radius, vt1.m_c);
CVertex v4(1, pt0 + right0 * radius, pt0);
double save_units = CArea::m_units;
CArea::m_units = 1.0;
AddVertex(v0, NULL);
AddVertex(v1, &v0);
AddVertex(v2, &v1);
AddVertex(v3, &v2);
AddVertex(v4, &v3);
CArea::m_units = save_units;
}
static void OffsetSpansWithObrounds(const CArea& area, TPolyPolygon &pp_new, double radius)
{
Clipper c;
for(std::list<CCurve>::const_iterator It = area.m_curves.begin(); It != area.m_curves.end(); It++)
{
pts_for_AddVertex.clear();
const CCurve& curve = *It;
const CVertex* prev_vertex = NULL;
for(std::list<CVertex>::const_iterator It2 = curve.m_vertices.begin(); It2 != curve.m_vertices.end(); It2++)
{
const CVertex& vertex = *It2;
if(prev_vertex)
{
MakeObround(prev_vertex->m_p, vertex, radius);
TPolygon loopy_polygon;
loopy_polygon.reserve(pts_for_AddVertex.size());
for(std::list<DoubleAreaPoint>::iterator It = pts_for_AddVertex.begin(); It != pts_for_AddVertex.end(); It++)
{
loopy_polygon.push_back(It->int_point());
}
c.AddPath(loopy_polygon, ptSubject, true);
pts_for_AddVertex.clear();
}
prev_vertex = &vertex;
}
}
pp_new.clear();
c.Execute(ctUnion, pp_new, pftNonZero, pftNonZero);
// reverse all the resulting polygons
TPolyPolygon copy = pp_new;
pp_new.clear();
pp_new.resize(copy.size());
for(unsigned int i = 0; i < copy.size(); i++)
{
const TPolygon& p = copy[i];
TPolygon p_new;
p_new.resize(p.size());
std::size_t size_minus_one = p.size() - 1;
for(std::size_t j = 0; j < p.size(); j++)p_new[j] = p[size_minus_one - j];
pp_new[i] = p_new;
}
}
static void MakePolyPoly( const CArea& area, TPolyPolygon &pp, bool reverse = true ){
pp.clear();
for(std::list<CCurve>::const_iterator It = area.m_curves.begin(); It != area.m_curves.end(); It++)
{
pts_for_AddVertex.clear();
const CCurve& curve = *It;
const CVertex* prev_vertex = NULL;
for(std::list<CVertex>::const_iterator It2 = curve.m_vertices.begin(); It2 != curve.m_vertices.end(); It2++)
{
const CVertex& vertex = *It2;
if(prev_vertex)AddVertex(vertex, prev_vertex);
prev_vertex = &vertex;
}
TPolygon p;
p.resize(pts_for_AddVertex.size());
if(reverse)
{
std::size_t i = pts_for_AddVertex.size() - 1;// clipper wants them the opposite way to CArea
for(std::list<DoubleAreaPoint>::iterator It = pts_for_AddVertex.begin(); It != pts_for_AddVertex.end(); It++, i--)
{
p[i] = It->int_point();
}
}
else
{
unsigned int i = 0;
for(std::list<DoubleAreaPoint>::iterator It = pts_for_AddVertex.begin(); It != pts_for_AddVertex.end(); It++, i++)
{
p[i] = It->int_point();
}
}
pp.push_back(p);
}
}
static void MakePoly(const CCurve& curve, TPolygon &p)
{
pts_for_AddVertex.clear();
const CVertex* prev_vertex = NULL;
for (std::list<CVertex>::const_iterator It2 = curve.m_vertices.begin(); It2 != curve.m_vertices.end(); It2++)
{
const CVertex& vertex = *It2;
if (prev_vertex)AddVertex(vertex, prev_vertex);
prev_vertex = &vertex;
}
p.resize(pts_for_AddVertex.size());
{
unsigned int i = 0;
for (std::list<DoubleAreaPoint>::iterator It = pts_for_AddVertex.begin(); It != pts_for_AddVertex.end(); It++, i++)
{
p[i] = It->int_point();
}
}
}
static void SetFromResult( CCurve& curve, const TPolygon& p, bool reverse = true )
{
for(unsigned int j = 0; j < p.size(); j++)
{
const IntPoint &pt = p[j];
DoubleAreaPoint dp(pt);
CVertex vertex(0, Point(dp.X / CArea::m_units, dp.Y / CArea::m_units), Point(0.0, 0.0));
if(reverse)curve.m_vertices.push_front(vertex);
else curve.m_vertices.push_back(vertex);
}
// make a copy of the first point at the end
if(reverse)curve.m_vertices.push_front(curve.m_vertices.back());
else curve.m_vertices.push_back(curve.m_vertices.front());
if(CArea::m_fit_arcs)curve.FitArcs();
}
static void SetFromResult( CArea& area, const TPolyPolygon& pp, bool reverse = true )
{
// delete existing geometry
area.m_curves.clear();
for(unsigned int i = 0; i < pp.size(); i++)
{
const TPolygon& p = pp[i];
area.m_curves.push_back(CCurve());
CCurve &curve = area.m_curves.back();
SetFromResult(curve, p, reverse);
}
}
void CArea::Subtract(const CArea& a2)
{
Clipper c;
TPolyPolygon pp1, pp2;
MakePolyPoly(*this, pp1);
MakePolyPoly(a2, pp2);
c.AddPaths(pp1, ptSubject, true);
c.AddPaths(pp2, ptClip, true);
TPolyPolygon solution;
c.Execute(ctDifference, solution);
SetFromResult(*this, solution);
}
void CArea::Intersect(const CArea& a2)
{
Clipper c;
TPolyPolygon pp1, pp2;
MakePolyPoly(*this, pp1);
MakePolyPoly(a2, pp2);
c.AddPaths(pp1, ptSubject, true);
c.AddPaths(pp2, ptClip, true);
TPolyPolygon solution;
c.Execute(ctIntersection, solution);
SetFromResult(*this, solution);
}
void CArea::Union(const CArea& a2)
{
Clipper c;
TPolyPolygon pp1, pp2;
MakePolyPoly(*this, pp1);
MakePolyPoly(a2, pp2);
c.AddPaths(pp1, ptSubject, true);
c.AddPaths(pp2, ptClip, true);
TPolyPolygon solution;
c.Execute(ctUnion, solution);
SetFromResult(*this, solution);
}
// static
CArea CArea::UniteCurves(std::list<CCurve> &curves)
{
Clipper c;
TPolyPolygon pp;
for (std::list<CCurve>::iterator It = curves.begin(); It != curves.end(); It++)
{
CCurve &curve = *It;
TPolygon p;
MakePoly(curve, p);
pp.push_back(p);
}
c.AddPaths(pp, ptSubject, true);
TPolyPolygon solution;
c.Execute(ctUnion, solution, pftNonZero, pftNonZero);
CArea area;
SetFromResult(area, solution);
return area;
}
void CArea::Xor(const CArea& a2)
{
Clipper c;
TPolyPolygon pp1, pp2;
MakePolyPoly(*this, pp1);
MakePolyPoly(a2, pp2);
c.AddPaths(pp1, ptSubject, true);
c.AddPaths(pp2, ptClip, true);
TPolyPolygon solution;
c.Execute(ctXor, solution);
SetFromResult(*this, solution);
}
void CArea::Offset(double inwards_value)
{
TPolyPolygon pp, pp2;
MakePolyPoly(*this, pp, false);
OffsetWithLoops(pp, pp2, inwards_value * m_units);
SetFromResult(*this, pp2, false);
this->Reorder();
}
void CArea::Thicken(double value)
{
TPolyPolygon pp;
OffsetSpansWithObrounds(*this, pp, value * m_units);
SetFromResult(*this, pp, false);
this->Reorder();
}
void UnFitArcs(CCurve &curve)
{
pts_for_AddVertex.clear();
const CVertex* prev_vertex = NULL;
for(std::list<CVertex>::const_iterator It2 = curve.m_vertices.begin(); It2 != curve.m_vertices.end(); It2++)
{
const CVertex& vertex = *It2;
AddVertex(vertex, prev_vertex);
prev_vertex = &vertex;
}
curve.m_vertices.clear();
for(std::list<DoubleAreaPoint>::iterator It = pts_for_AddVertex.begin(); It != pts_for_AddVertex.end(); It++)
{
DoubleAreaPoint &pt = *It;
CVertex vertex(0, Point(pt.X / CArea::m_units, pt.Y / CArea::m_units), Point(0.0, 0.0));
curve.m_vertices.push_back(vertex);
}
}