724 lines
21 KiB
C++
724 lines
21 KiB
C++
/*******************************************************************************
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* Author : Angus Johnson *
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* Date : 28 November 2023 *
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* Website : http://www.angusj.com *
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* Copyright : Angus Johnson 2010-2023 *
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* Purpose : Path Offset (Inflate/Shrink) *
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* License : http://www.boost.org/LICENSE_1_0.txt *
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*******************************************************************************/
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#include <cmath>
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#include "clipper2/clipper.h"
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#include "clipper2/clipper.offset.h"
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namespace Clipper2Lib {
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const double default_arc_tolerance = 0.25;
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const double floating_point_tolerance = 1e-12;
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//------------------------------------------------------------------------------
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// Miscellaneous methods
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//------------------------------------------------------------------------------
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inline bool ToggleBoolIf(bool val, bool condition)
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{
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return condition ? !val : val;
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}
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void GetMultiBounds(const Paths64& paths, std::vector<Rect64>& recList)
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{
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recList.reserve(paths.size());
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for (const Path64& path : paths)
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{
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if (path.size() < 1)
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{
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recList.push_back(InvalidRect64);
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continue;
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}
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int64_t x = path[0].x, y = path[0].y;
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Rect64 r = Rect64(x, y, x, y);
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for (const Point64& pt : path)
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{
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if (pt.y > r.bottom) r.bottom = pt.y;
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else if (pt.y < r.top) r.top = pt.y;
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if (pt.x > r.right) r.right = pt.x;
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else if (pt.x < r.left) r.left = pt.x;
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}
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recList.push_back(r);
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}
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}
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bool ValidateBounds(std::vector<Rect64>& recList, double delta)
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{
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int64_t int_delta = static_cast<int64_t>(delta);
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int64_t big = MAX_COORD - int_delta;
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int64_t small = MIN_COORD + int_delta;
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for (const Rect64& r : recList)
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{
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if (!r.IsValid()) continue; // ignore invalid paths
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else if (r.left < small || r.right > big ||
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r.top < small || r.bottom > big) return false;
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}
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return true;
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}
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int GetLowestClosedPathIdx(std::vector<Rect64>& boundsList)
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{
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int i = -1, result = -1;
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Point64 botPt = Point64(INT64_MAX, INT64_MIN);
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for (const Rect64& r : boundsList)
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{
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++i;
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if (!r.IsValid()) continue; // ignore invalid paths
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else if (r.bottom > botPt.y || (r.bottom == botPt.y && r.left < botPt.x))
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{
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botPt = Point64(r.left, r.bottom);
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result = static_cast<int>(i);
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}
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}
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return result;
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}
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PointD GetUnitNormal(const Point64& pt1, const Point64& pt2)
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{
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double dx, dy, inverse_hypot;
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if (pt1 == pt2) return PointD(0.0, 0.0);
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dx = static_cast<double>(pt2.x - pt1.x);
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dy = static_cast<double>(pt2.y - pt1.y);
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inverse_hypot = 1.0 / hypot(dx, dy);
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dx *= inverse_hypot;
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dy *= inverse_hypot;
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return PointD(dy, -dx);
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}
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inline bool AlmostZero(double value, double epsilon = 0.001)
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{
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return std::fabs(value) < epsilon;
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}
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inline double Hypot(double x, double y)
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{
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//see https://stackoverflow.com/a/32436148/359538
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return std::sqrt(x * x + y * y);
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}
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inline PointD NormalizeVector(const PointD& vec)
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{
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double h = Hypot(vec.x, vec.y);
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if (AlmostZero(h)) return PointD(0,0);
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double inverseHypot = 1 / h;
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return PointD(vec.x * inverseHypot, vec.y * inverseHypot);
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}
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inline PointD GetAvgUnitVector(const PointD& vec1, const PointD& vec2)
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{
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return NormalizeVector(PointD(vec1.x + vec2.x, vec1.y + vec2.y));
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}
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inline bool IsClosedPath(EndType et)
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{
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return et == EndType::Polygon || et == EndType::Joined;
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}
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inline Point64 GetPerpendic(const Point64& pt, const PointD& norm, double delta)
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{
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#ifdef USINGZ
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return Point64(pt.x + norm.x * delta, pt.y + norm.y * delta, pt.z);
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#else
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return Point64(pt.x + norm.x * delta, pt.y + norm.y * delta);
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#endif
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}
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inline PointD GetPerpendicD(const Point64& pt, const PointD& norm, double delta)
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{
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#ifdef USINGZ
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return PointD(pt.x + norm.x * delta, pt.y + norm.y * delta, pt.z);
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#else
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return PointD(pt.x + norm.x * delta, pt.y + norm.y * delta);
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#endif
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}
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inline void NegatePath(PathD& path)
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{
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for (PointD& pt : path)
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{
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pt.x = -pt.x;
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pt.y = -pt.y;
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#ifdef USINGZ
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pt.z = pt.z;
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#endif
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}
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}
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//------------------------------------------------------------------------------
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// ClipperOffset::Group methods
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//------------------------------------------------------------------------------
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ClipperOffset::Group::Group(const Paths64& _paths, JoinType _join_type, EndType _end_type):
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paths_in(_paths), join_type(_join_type), end_type(_end_type)
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{
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bool is_joined =
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(end_type == EndType::Polygon) ||
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(end_type == EndType::Joined);
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for (Path64& p: paths_in)
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StripDuplicates(p, is_joined);
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// get bounds of each path --> bounds_list
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GetMultiBounds(paths_in, bounds_list);
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if (end_type == EndType::Polygon)
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{
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is_hole_list.reserve(paths_in.size());
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for (const Path64& path : paths_in)
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is_hole_list.push_back(Area(path) < 0);
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lowest_path_idx = GetLowestClosedPathIdx(bounds_list);
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// the lowermost path must be an outer path, so if its orientation is negative,
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// then flag the whole group is 'reversed' (will negate delta etc.)
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// as this is much more efficient than reversing every path.
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is_reversed = (lowest_path_idx >= 0) && is_hole_list[lowest_path_idx];
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if (is_reversed) is_hole_list.flip();
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}
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else
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{
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lowest_path_idx = -1;
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is_reversed = false;
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is_hole_list.resize(paths_in.size());
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}
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}
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//------------------------------------------------------------------------------
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// ClipperOffset methods
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//------------------------------------------------------------------------------
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void ClipperOffset::AddPath(const Path64& path, JoinType jt_, EndType et_)
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{
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Paths64 paths;
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paths.push_back(path);
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AddPaths(paths, jt_, et_);
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}
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void ClipperOffset::AddPaths(const Paths64 &paths, JoinType jt_, EndType et_)
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{
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if (paths.size() == 0) return;
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groups_.push_back(Group(paths, jt_, et_));
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}
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void ClipperOffset::BuildNormals(const Path64& path)
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{
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norms.clear();
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norms.reserve(path.size());
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if (path.size() == 0) return;
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Path64::const_iterator path_iter, path_stop_iter = --path.cend();
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for (path_iter = path.cbegin(); path_iter != path_stop_iter; ++path_iter)
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norms.push_back(GetUnitNormal(*path_iter,*(path_iter +1)));
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norms.push_back(GetUnitNormal(*path_stop_iter, *(path.cbegin())));
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}
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inline PointD TranslatePoint(const PointD& pt, double dx, double dy)
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{
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#ifdef USINGZ
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return PointD(pt.x + dx, pt.y + dy, pt.z);
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#else
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return PointD(pt.x + dx, pt.y + dy);
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#endif
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}
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inline PointD ReflectPoint(const PointD& pt, const PointD& pivot)
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{
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#ifdef USINGZ
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return PointD(pivot.x + (pivot.x - pt.x), pivot.y + (pivot.y - pt.y), pt.z);
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#else
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return PointD(pivot.x + (pivot.x - pt.x), pivot.y + (pivot.y - pt.y));
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#endif
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}
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PointD IntersectPoint(const PointD& pt1a, const PointD& pt1b,
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const PointD& pt2a, const PointD& pt2b)
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{
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if (pt1a.x == pt1b.x) //vertical
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{
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if (pt2a.x == pt2b.x) return PointD(0, 0);
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double m2 = (pt2b.y - pt2a.y) / (pt2b.x - pt2a.x);
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double b2 = pt2a.y - m2 * pt2a.x;
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return PointD(pt1a.x, m2 * pt1a.x + b2);
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}
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else if (pt2a.x == pt2b.x) //vertical
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{
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double m1 = (pt1b.y - pt1a.y) / (pt1b.x - pt1a.x);
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double b1 = pt1a.y - m1 * pt1a.x;
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return PointD(pt2a.x, m1 * pt2a.x + b1);
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}
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else
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{
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double m1 = (pt1b.y - pt1a.y) / (pt1b.x - pt1a.x);
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double b1 = pt1a.y - m1 * pt1a.x;
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double m2 = (pt2b.y - pt2a.y) / (pt2b.x - pt2a.x);
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double b2 = pt2a.y - m2 * pt2a.x;
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if (m1 == m2) return PointD(0, 0);
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double x = (b2 - b1) / (m1 - m2);
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return PointD(x, m1 * x + b1);
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}
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}
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void ClipperOffset::DoBevel(const Path64& path, size_t j, size_t k)
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{
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PointD pt1, pt2;
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if (j == k)
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{
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double abs_delta = std::abs(group_delta_);
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pt1 = PointD(path[j].x - abs_delta * norms[j].x, path[j].y - abs_delta * norms[j].y);
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pt2 = PointD(path[j].x + abs_delta * norms[j].x, path[j].y + abs_delta * norms[j].y);
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}
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else
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{
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pt1 = PointD(path[j].x + group_delta_ * norms[k].x, path[j].y + group_delta_ * norms[k].y);
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pt2 = PointD(path[j].x + group_delta_ * norms[j].x, path[j].y + group_delta_ * norms[j].y);
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}
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path_out.push_back(Point64(pt1));
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path_out.push_back(Point64(pt2));
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}
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void ClipperOffset::DoSquare(const Path64& path, size_t j, size_t k)
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{
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PointD vec;
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if (j == k)
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vec = PointD(norms[j].y, -norms[j].x);
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else
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vec = GetAvgUnitVector(
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PointD(-norms[k].y, norms[k].x),
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PointD(norms[j].y, -norms[j].x));
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double abs_delta = std::abs(group_delta_);
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// now offset the original vertex delta units along unit vector
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PointD ptQ = PointD(path[j]);
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ptQ = TranslatePoint(ptQ, abs_delta * vec.x, abs_delta * vec.y);
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// get perpendicular vertices
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PointD pt1 = TranslatePoint(ptQ, group_delta_ * vec.y, group_delta_ * -vec.x);
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PointD pt2 = TranslatePoint(ptQ, group_delta_ * -vec.y, group_delta_ * vec.x);
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// get 2 vertices along one edge offset
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PointD pt3 = GetPerpendicD(path[k], norms[k], group_delta_);
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if (j == k)
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{
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PointD pt4 = PointD(pt3.x + vec.x * group_delta_, pt3.y + vec.y * group_delta_);
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PointD pt = IntersectPoint(pt1, pt2, pt3, pt4);
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#ifdef USINGZ
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pt.z = ptQ.z;
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#endif
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//get the second intersect point through reflecion
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path_out.push_back(Point64(ReflectPoint(pt, ptQ)));
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path_out.push_back(Point64(pt));
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}
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else
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{
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PointD pt4 = GetPerpendicD(path[j], norms[k], group_delta_);
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PointD pt = IntersectPoint(pt1, pt2, pt3, pt4);
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#ifdef USINGZ
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pt.z = ptQ.z;
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#endif
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path_out.push_back(Point64(pt));
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//get the second intersect point through reflecion
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path_out.push_back(Point64(ReflectPoint(pt, ptQ)));
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}
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}
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void ClipperOffset::DoMiter(const Path64& path, size_t j, size_t k, double cos_a)
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{
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double q = group_delta_ / (cos_a + 1);
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#ifdef USINGZ
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path_out.push_back(Point64(
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path[j].x + (norms[k].x + norms[j].x) * q,
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path[j].y + (norms[k].y + norms[j].y) * q,
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path[j].z));
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#else
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path_out.push_back(Point64(
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path[j].x + (norms[k].x + norms[j].x) * q,
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path[j].y + (norms[k].y + norms[j].y) * q));
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#endif
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}
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void ClipperOffset::DoRound(const Path64& path, size_t j, size_t k, double angle)
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{
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if (deltaCallback64_) {
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// when deltaCallback64_ is assigned, group_delta_ won't be constant,
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// so we'll need to do the following calculations for *every* vertex.
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double abs_delta = std::fabs(group_delta_);
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double arcTol = (arc_tolerance_ > floating_point_tolerance ?
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std::min(abs_delta, arc_tolerance_) :
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std::log10(2 + abs_delta) * default_arc_tolerance);
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double steps_per_360 = std::min(PI / std::acos(1 - arcTol / abs_delta), abs_delta * PI);
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step_sin_ = std::sin(2 * PI / steps_per_360);
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step_cos_ = std::cos(2 * PI / steps_per_360);
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if (group_delta_ < 0.0) step_sin_ = -step_sin_;
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steps_per_rad_ = steps_per_360 / (2 * PI);
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}
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Point64 pt = path[j];
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PointD offsetVec = PointD(norms[k].x * group_delta_, norms[k].y * group_delta_);
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if (j == k) offsetVec.Negate();
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#ifdef USINGZ
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path_out.push_back(Point64(pt.x + offsetVec.x, pt.y + offsetVec.y, pt.z));
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#else
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path_out.push_back(Point64(pt.x + offsetVec.x, pt.y + offsetVec.y));
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#endif
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int steps = static_cast<int>(std::ceil(steps_per_rad_ * std::abs(angle))); // #448, #456
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for (int i = 1; i < steps; ++i) // ie 1 less than steps
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{
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offsetVec = PointD(offsetVec.x * step_cos_ - step_sin_ * offsetVec.y,
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offsetVec.x * step_sin_ + offsetVec.y * step_cos_);
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#ifdef USINGZ
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path_out.push_back(Point64(pt.x + offsetVec.x, pt.y + offsetVec.y, pt.z));
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#else
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path_out.push_back(Point64(pt.x + offsetVec.x, pt.y + offsetVec.y));
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#endif
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}
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path_out.push_back(GetPerpendic(path[j], norms[j], group_delta_));
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}
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void ClipperOffset::OffsetPoint(Group& group, const Path64& path, size_t j, size_t k)
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{
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// Let A = change in angle where edges join
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// A == 0: ie no change in angle (flat join)
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// A == PI: edges 'spike'
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// sin(A) < 0: right turning
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// cos(A) < 0: change in angle is more than 90 degree
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if (path[j] == path[k]) { k = j; return; }
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double sin_a = CrossProduct(norms[j], norms[k]);
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double cos_a = DotProduct(norms[j], norms[k]);
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if (sin_a > 1.0) sin_a = 1.0;
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else if (sin_a < -1.0) sin_a = -1.0;
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if (deltaCallback64_) {
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group_delta_ = deltaCallback64_(path, norms, j, k);
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if (group.is_reversed) group_delta_ = -group_delta_;
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}
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if (std::fabs(group_delta_) <= floating_point_tolerance)
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{
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path_out.push_back(path[j]);
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return;
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}
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if (cos_a > -0.99 && (sin_a * group_delta_ < 0)) // test for concavity first (#593)
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{
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// is concave
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path_out.push_back(GetPerpendic(path[j], norms[k], group_delta_));
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// this extra point is the only (simple) way to ensure that
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// path reversals are fully cleaned with the trailing clipper
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path_out.push_back(path[j]); // (#405)
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path_out.push_back(GetPerpendic(path[j], norms[j], group_delta_));
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}
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else if (cos_a > 0.999 && join_type_ != JoinType::Round)
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{
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// almost straight - less than 2.5 degree (#424, #482, #526 & #724)
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DoMiter(path, j, k, cos_a);
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}
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else if (join_type_ == JoinType::Miter)
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{
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// miter unless the angle is sufficiently acute to exceed ML
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if (cos_a > temp_lim_ - 1) DoMiter(path, j, k, cos_a);
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else DoSquare(path, j, k);
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}
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else if (join_type_ == JoinType::Round)
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DoRound(path, j, k, std::atan2(sin_a, cos_a));
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else if ( join_type_ == JoinType::Bevel)
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DoBevel(path, j, k);
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else
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DoSquare(path, j, k);
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}
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void ClipperOffset::OffsetPolygon(Group& group, const Path64& path)
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{
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path_out.clear();
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for (Path64::size_type j = 0, k = path.size() -1; j < path.size(); k = j, ++j)
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OffsetPoint(group, path, j, k);
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solution.push_back(path_out);
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}
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void ClipperOffset::OffsetOpenJoined(Group& group, const Path64& path)
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{
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OffsetPolygon(group, path);
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Path64 reverse_path(path);
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std::reverse(reverse_path.begin(), reverse_path.end());
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//rebuild normals // BuildNormals(path);
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std::reverse(norms.begin(), norms.end());
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norms.push_back(norms[0]);
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norms.erase(norms.begin());
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NegatePath(norms);
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|
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OffsetPolygon(group, reverse_path);
|
|
}
|
|
|
|
void ClipperOffset::OffsetOpenPath(Group& group, const Path64& path)
|
|
{
|
|
// do the line start cap
|
|
if (deltaCallback64_) group_delta_ = deltaCallback64_(path, norms, 0, 0);
|
|
|
|
if (std::fabs(group_delta_) <= floating_point_tolerance)
|
|
path_out.push_back(path[0]);
|
|
else
|
|
{
|
|
switch (end_type_)
|
|
{
|
|
case EndType::Butt:
|
|
DoBevel(path, 0, 0);
|
|
break;
|
|
case EndType::Round:
|
|
DoRound(path, 0, 0, PI);
|
|
break;
|
|
default:
|
|
DoSquare(path, 0, 0);
|
|
break;
|
|
}
|
|
}
|
|
|
|
size_t highI = path.size() - 1;
|
|
// offset the left side going forward
|
|
for (Path64::size_type j = 1, k = 0; j < highI; k = j, ++j)
|
|
OffsetPoint(group, path, j, k);
|
|
|
|
// reverse normals
|
|
for (size_t i = highI; i > 0; --i)
|
|
norms[i] = PointD(-norms[i - 1].x, -norms[i - 1].y);
|
|
norms[0] = norms[highI];
|
|
|
|
// do the line end cap
|
|
if (deltaCallback64_)
|
|
group_delta_ = deltaCallback64_(path, norms, highI, highI);
|
|
|
|
if (std::fabs(group_delta_) <= floating_point_tolerance)
|
|
path_out.push_back(path[highI]);
|
|
else
|
|
{
|
|
switch (end_type_)
|
|
{
|
|
case EndType::Butt:
|
|
DoBevel(path, highI, highI);
|
|
break;
|
|
case EndType::Round:
|
|
DoRound(path, highI, highI, PI);
|
|
break;
|
|
default:
|
|
DoSquare(path, highI, highI);
|
|
break;
|
|
}
|
|
}
|
|
|
|
for (size_t j = highI, k = 0; j > 0; k = j, --j)
|
|
OffsetPoint(group, path, j, k);
|
|
solution.push_back(path_out);
|
|
}
|
|
|
|
void ClipperOffset::DoGroupOffset(Group& group)
|
|
{
|
|
if (group.end_type == EndType::Polygon)
|
|
{
|
|
// a straight path (2 points) can now also be 'polygon' offset
|
|
// where the ends will be treated as (180 deg.) joins
|
|
if (group.lowest_path_idx < 0) delta_ = std::abs(delta_);
|
|
group_delta_ = (group.is_reversed) ? -delta_ : delta_;
|
|
}
|
|
else
|
|
group_delta_ = std::abs(delta_);// *0.5;
|
|
|
|
double abs_delta = std::fabs(group_delta_);
|
|
if (!ValidateBounds(group.bounds_list, abs_delta))
|
|
{
|
|
DoError(range_error_i);
|
|
error_code_ |= range_error_i;
|
|
return;
|
|
}
|
|
|
|
join_type_ = group.join_type;
|
|
end_type_ = group.end_type;
|
|
|
|
if (group.join_type == JoinType::Round || group.end_type == EndType::Round)
|
|
{
|
|
// calculate a sensible number of steps (for 360 deg for the given offset)
|
|
// arcTol - when arc_tolerance_ is undefined (0), the amount of
|
|
// curve imprecision that's allowed is based on the size of the
|
|
// offset (delta). Obviously very large offsets will almost always
|
|
// require much less precision. See also offset_triginometry2.svg
|
|
double arcTol = (arc_tolerance_ > floating_point_tolerance ?
|
|
std::min(abs_delta, arc_tolerance_) :
|
|
std::log10(2 + abs_delta) * default_arc_tolerance);
|
|
|
|
double steps_per_360 = std::min(PI / std::acos(1 - arcTol / abs_delta), abs_delta * PI);
|
|
step_sin_ = std::sin(2 * PI / steps_per_360);
|
|
step_cos_ = std::cos(2 * PI / steps_per_360);
|
|
if (group_delta_ < 0.0) step_sin_ = -step_sin_;
|
|
steps_per_rad_ = steps_per_360 / (2 * PI);
|
|
}
|
|
|
|
std::vector<Rect64>::const_iterator path_rect_it = group.bounds_list.cbegin();
|
|
std::vector<bool>::const_iterator is_hole_it = group.is_hole_list.cbegin();
|
|
Paths64::const_iterator path_in_it = group.paths_in.cbegin();
|
|
for ( ; path_in_it != group.paths_in.cend(); ++path_in_it, ++path_rect_it, ++is_hole_it)
|
|
{
|
|
if (!path_rect_it->IsValid()) continue;
|
|
Path64::size_type pathLen = path_in_it->size();
|
|
path_out.clear();
|
|
|
|
if (pathLen == 1) // single point
|
|
{
|
|
if (group_delta_ < 1) continue;
|
|
const Point64& pt = (*path_in_it)[0];
|
|
//single vertex so build a circle or square ...
|
|
if (group.join_type == JoinType::Round)
|
|
{
|
|
double radius = abs_delta;
|
|
int steps = static_cast<int>(std::ceil(steps_per_rad_ * 2 * PI)); //#617
|
|
path_out = Ellipse(pt, radius, radius, steps);
|
|
#ifdef USINGZ
|
|
for (auto& p : path_out) p.z = pt.z;
|
|
#endif
|
|
}
|
|
else
|
|
{
|
|
int d = (int)std::ceil(abs_delta);
|
|
Rect64 r = Rect64(pt.x - d, pt.y - d, pt.x + d, pt.y + d);
|
|
path_out = r.AsPath();
|
|
#ifdef USINGZ
|
|
for (auto& p : path_out) p.z = pt.z;
|
|
#endif
|
|
}
|
|
solution.push_back(path_out);
|
|
continue;
|
|
} // end of offsetting a single point
|
|
|
|
// when shrinking outer paths, make sure they can shrink this far (#593)
|
|
// also when shrinking holes, make sure they too can shrink this far (#715)
|
|
if ((group_delta_ > 0) == ToggleBoolIf(*is_hole_it, group.is_reversed) &&
|
|
(std::min(path_rect_it->Width(), path_rect_it->Height()) <= -group_delta_ * 2) )
|
|
continue;
|
|
|
|
if ((pathLen == 2) && (group.end_type == EndType::Joined))
|
|
end_type_ = (group.join_type == JoinType::Round) ?
|
|
EndType::Round :
|
|
EndType::Square;
|
|
|
|
BuildNormals(*path_in_it);
|
|
if (end_type_ == EndType::Polygon) OffsetPolygon(group, *path_in_it);
|
|
else if (end_type_ == EndType::Joined) OffsetOpenJoined(group, *path_in_it);
|
|
else OffsetOpenPath(group, *path_in_it);
|
|
}
|
|
}
|
|
|
|
|
|
size_t ClipperOffset::CalcSolutionCapacity()
|
|
{
|
|
size_t result = 0;
|
|
for (const Group& g : groups_)
|
|
result += (g.end_type == EndType::Joined) ? g.paths_in.size() * 2 : g.paths_in.size();
|
|
return result;
|
|
}
|
|
|
|
bool ClipperOffset::CheckReverseOrientation()
|
|
{
|
|
// nb: this assumes there's consistency in orientation between groups
|
|
bool is_reversed_orientation = false;
|
|
for (const Group& g : groups_)
|
|
if (g.end_type == EndType::Polygon)
|
|
{
|
|
is_reversed_orientation = g.is_reversed;
|
|
break;
|
|
}
|
|
return is_reversed_orientation;
|
|
}
|
|
|
|
void ClipperOffset::ExecuteInternal(double delta)
|
|
{
|
|
error_code_ = 0;
|
|
solution.clear();
|
|
if (groups_.size() == 0) return;
|
|
solution.reserve(CalcSolutionCapacity());
|
|
|
|
if (std::abs(delta) < 0.5) // ie: offset is insignificant
|
|
{
|
|
Paths64::size_type sol_size = 0;
|
|
for (const Group& group : groups_) sol_size += group.paths_in.size();
|
|
solution.reserve(sol_size);
|
|
for (const Group& group : groups_)
|
|
copy(group.paths_in.begin(), group.paths_in.end(), back_inserter(solution));
|
|
return;
|
|
}
|
|
|
|
temp_lim_ = (miter_limit_ <= 1) ?
|
|
2.0 :
|
|
2.0 / (miter_limit_ * miter_limit_);
|
|
|
|
delta_ = delta;
|
|
std::vector<Group>::iterator git;
|
|
for (git = groups_.begin(); git != groups_.end(); ++git)
|
|
{
|
|
DoGroupOffset(*git);
|
|
if (!error_code_) continue; // all OK
|
|
solution.clear();
|
|
}
|
|
}
|
|
|
|
void ClipperOffset::Execute(double delta, Paths64& paths)
|
|
{
|
|
paths.clear();
|
|
|
|
ExecuteInternal(delta);
|
|
if (!solution.size()) return;
|
|
|
|
bool paths_reversed = CheckReverseOrientation();
|
|
//clean up self-intersections ...
|
|
Clipper64 c;
|
|
c.PreserveCollinear(false);
|
|
//the solution should retain the orientation of the input
|
|
c.ReverseSolution(reverse_solution_ != paths_reversed);
|
|
#ifdef USINGZ
|
|
if (zCallback64_) { c.SetZCallback(zCallback64_); }
|
|
#endif
|
|
c.AddSubject(solution);
|
|
if (paths_reversed)
|
|
c.Execute(ClipType::Union, FillRule::Negative, paths);
|
|
else
|
|
c.Execute(ClipType::Union, FillRule::Positive, paths);
|
|
}
|
|
|
|
|
|
void ClipperOffset::Execute(double delta, PolyTree64& polytree)
|
|
{
|
|
polytree.Clear();
|
|
|
|
ExecuteInternal(delta);
|
|
if (!solution.size()) return;
|
|
|
|
bool paths_reversed = CheckReverseOrientation();
|
|
//clean up self-intersections ...
|
|
Clipper64 c;
|
|
c.PreserveCollinear(false);
|
|
//the solution should retain the orientation of the input
|
|
c.ReverseSolution (reverse_solution_ != paths_reversed);
|
|
#ifdef USINGZ
|
|
if (zCallback64_) {
|
|
c.SetZCallback(zCallback64_);
|
|
}
|
|
#endif
|
|
c.AddSubject(solution);
|
|
|
|
|
|
if (paths_reversed)
|
|
c.Execute(ClipType::Union, FillRule::Negative, polytree);
|
|
else
|
|
c.Execute(ClipType::Union, FillRule::Positive, polytree);
|
|
}
|
|
|
|
void ClipperOffset::Execute(DeltaCallback64 delta_cb, Paths64& paths)
|
|
{
|
|
deltaCallback64_ = delta_cb;
|
|
Execute(1.0, paths);
|
|
}
|
|
|
|
} // namespace
|