Lothario
/
axmol
mirror of https://github.com/axmolengine/axmol.git
1
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity
axmol/thirdparty/clipper2/clipper.h

886 lines
27 KiB
C++
Raw Blame History

/*******************************************************************************
* Author : Angus Johnson *
* Date : 27 January 2023 *
* Website : http://www.angusj.com *
* Copyright : Angus Johnson 2010-2023 *
* Purpose : This module provides a simple interface to the Clipper Library *
* License : http://www.boost.org/LICENSE_1_0.txt *
*******************************************************************************/
#ifndef CLIPPER_H
#define CLIPPER_H
#include <cstdlib>
#include <vector>
#include "clipper.core.h"
#include "clipper.engine.h"
#include "clipper.offset.h"
#include "clipper.minkowski.h"
#include "clipper.rectclip.h"
namespace Clipper2Lib {
inline Paths64 BooleanOp(ClipType cliptype, FillRule fillrule,
const Paths64& subjects, const Paths64& clips)
{
Paths64 result;
Clipper64 clipper;
clipper.AddSubject(subjects);
clipper.AddClip(clips);
clipper.Execute(cliptype, fillrule, result);
return result;
}
inline void BooleanOp(ClipType cliptype, FillRule fillrule,
const Paths64& subjects, const Paths64& clips, PolyTree64& solution)
{
Paths64 sol_open;
Clipper64 clipper;
clipper.AddSubject(subjects);
clipper.AddClip(clips);
clipper.Execute(cliptype, fillrule, solution, sol_open);
}
inline PathsD BooleanOp(ClipType cliptype, FillRule fillrule,
const PathsD& subjects, const PathsD& clips, int decimal_prec = 2)
{
CheckPrecision(decimal_prec);
PathsD result;
ClipperD clipper(decimal_prec);
clipper.AddSubject(subjects);
clipper.AddClip(clips);
clipper.Execute(cliptype, fillrule, result);
return result;
}
inline void BooleanOp(ClipType cliptype, FillRule fillrule,
const PathsD& subjects, const PathsD& clips,
PolyTreeD& polytree, int decimal_prec = 2)
{
CheckPrecision(decimal_prec);
PathsD result;
ClipperD clipper(decimal_prec);
clipper.AddSubject(subjects);
clipper.AddClip(clips);
clipper.Execute(cliptype, fillrule, polytree);
}
inline Paths64 Intersect(const Paths64& subjects, const Paths64& clips, FillRule fillrule)
{
return BooleanOp(ClipType::Intersection, fillrule, subjects, clips);
}
inline PathsD Intersect(const PathsD& subjects, const PathsD& clips, FillRule fillrule, int decimal_prec = 2)
{
return BooleanOp(ClipType::Intersection, fillrule, subjects, clips, decimal_prec);
}
inline Paths64 Union(const Paths64& subjects, const Paths64& clips, FillRule fillrule)
{
return BooleanOp(ClipType::Union, fillrule, subjects, clips);
}
inline PathsD Union(const PathsD& subjects, const PathsD& clips, FillRule fillrule, int decimal_prec = 2)
{
return BooleanOp(ClipType::Union, fillrule, subjects, clips, decimal_prec);
}
inline Paths64 Union(const Paths64& subjects, FillRule fillrule)
{
Paths64 result;
Clipper64 clipper;
clipper.AddSubject(subjects);
clipper.Execute(ClipType::Union, fillrule, result);
return result;
}
inline PathsD Union(const PathsD& subjects, FillRule fillrule, int decimal_prec = 2)
{
CheckPrecision(decimal_prec);
PathsD result;
ClipperD clipper(decimal_prec);
clipper.AddSubject(subjects);
clipper.Execute(ClipType::Union, fillrule, result);
return result;
}
inline Paths64 Difference(const Paths64& subjects, const Paths64& clips, FillRule fillrule)
{
return BooleanOp(ClipType::Difference, fillrule, subjects, clips);
}
inline PathsD Difference(const PathsD& subjects, const PathsD& clips, FillRule fillrule, int decimal_prec = 2)
{
return BooleanOp(ClipType::Difference, fillrule, subjects, clips, decimal_prec);
}
inline Paths64 Xor(const Paths64& subjects, const Paths64& clips, FillRule fillrule)
{
return BooleanOp(ClipType::Xor, fillrule, subjects, clips);
}
inline PathsD Xor(const PathsD& subjects, const PathsD& clips, FillRule fillrule, int decimal_prec = 2)
{
return BooleanOp(ClipType::Xor, fillrule, subjects, clips, decimal_prec);
}
inline Paths64 InflatePaths(const Paths64& paths, double delta,
JoinType jt, EndType et, double miter_limit = 2.0)
{
ClipperOffset clip_offset(miter_limit);
clip_offset.AddPaths(paths, jt, et);
return clip_offset.Execute(delta);
}
inline PathsD InflatePaths(const PathsD& paths, double delta,
JoinType jt, EndType et, double miter_limit = 2.0, int precision = 2)
{
CheckPrecision(precision);
const double scale = std::pow(10, precision);
ClipperOffset clip_offset(miter_limit);
clip_offset.AddPaths(ScalePaths<int64_t,double>(paths, scale), jt, et);
Paths64 tmp = clip_offset.Execute(delta * scale);
return ScalePaths<double, int64_t>(tmp, 1 / scale);
}
inline Path64 TranslatePath(const Path64& path, int64_t dx, int64_t dy)
{
Path64 result;
result.reserve(path.size());
std::transform(path.begin(), path.end(), back_inserter(result),
[dx, dy](const auto& pt) { return Point64(pt.x + dx, pt.y +dy); });
return result;
}
inline PathD TranslatePath(const PathD& path, double dx, double dy)
{
PathD result;
result.reserve(path.size());
std::transform(path.begin(), path.end(), back_inserter(result),
[dx, dy](const auto& pt) { return PointD(pt.x + dx, pt.y + dy); });
return result;
}
inline Paths64 TranslatePaths(const Paths64& paths, int64_t dx, int64_t dy)
{
Paths64 result;
result.reserve(paths.size());
std::transform(paths.begin(), paths.end(), back_inserter(result),
[dx, dy](const auto& path) { return TranslatePath(path, dx, dy); });
return result;
}
inline PathsD TranslatePaths(const PathsD& paths, double dx, double dy)
{
PathsD result;
result.reserve(paths.size());
std::transform(paths.begin(), paths.end(), back_inserter(result),
[dx, dy](const auto& path) { return TranslatePath(path, dx, dy); });
return result;
}
inline Path64 RectClip(const Rect64& rect, const Path64& path)
{
if (rect.IsEmpty() || path.empty()) return Path64();
Rect64 pathRec = Bounds(path);
if (!rect.Intersects(pathRec)) return Path64();
if (rect.Contains(pathRec)) return path;
class RectClip rc(rect);
return rc.Execute(path);
}
inline Paths64 RectClip(const Rect64& rect, const Paths64& paths)
{
if (rect.IsEmpty() || paths.empty()) return Paths64();
class RectClip rc(rect);
Paths64 result;
result.reserve(paths.size());
for (const Path64& p : paths)
{
Rect64 pathRec = Bounds(p);
if (!rect.Intersects(pathRec))
continue;
else if (rect.Contains(pathRec))
result.push_back(p);
else
{
Path64 p2 = rc.Execute(p);
if (!p2.empty()) result.push_back(std::move(p2));
}
}
return result;
}
inline PathD RectClip(const RectD& rect, const PathD& path, int precision = 2)
{
if (rect.IsEmpty() || path.empty() ||
!rect.Contains(Bounds(path))) return PathD();
CheckPrecision(precision);
const double scale = std::pow(10, precision);
Rect64 r = ScaleRect<int64_t, double>(rect, scale);
class RectClip rc(r);
Path64 p = ScalePath<int64_t, double>(path, scale);
return ScalePath<double, int64_t>(rc.Execute(p), 1 / scale);
}
inline PathsD RectClip(const RectD& rect, const PathsD& paths, int precision = 2)
{
if (rect.IsEmpty() || paths.empty()) return PathsD();
CheckPrecision(precision);
const double scale = std::pow(10, precision);
Rect64 r = ScaleRect<int64_t, double>(rect, scale);
class RectClip rc(r);
PathsD result;
result.reserve(paths.size());
for (const PathD& path : paths)
{
RectD pathRec = Bounds(path);
if (!rect.Intersects(pathRec))
continue;
else if (rect.Contains(pathRec))
result.push_back(path);
else
{
Path64 p = ScalePath<int64_t, double>(path, scale);
p = rc.Execute(p);
if (!p.empty())
result.push_back(ScalePath<double, int64_t>(p, 1 / scale));
}
}
return result;
}
inline Paths64 RectClipLines(const Rect64& rect, const Path64& path)
{
Paths64 result;
if (rect.IsEmpty() || path.empty()) return result;
Rect64 pathRec = Bounds(path);
if (!rect.Intersects(pathRec)) return result;
if (rect.Contains(pathRec))
{
result.push_back(path);
return result;
}
class RectClipLines rcl(rect);
return rcl.Execute(path);
}
inline Paths64 RectClipLines(const Rect64& rect, const Paths64& paths)
{
Paths64 result;
if (rect.IsEmpty() || paths.empty()) return result;
class RectClipLines rcl(rect);
for (const Path64& p : paths)
{
Rect64 pathRec = Bounds(p);
if (!rect.Intersects(pathRec))
continue;
else if (rect.Contains(pathRec))
result.push_back(p);
else
{
Paths64 pp = rcl.Execute(p);
if (!pp.empty())
result.insert(result.end(), pp.begin(), pp.end());
}
}
return result;
}
inline PathsD RectClipLines(const RectD& rect, const PathD& path, int precision = 2)
{
if (rect.IsEmpty() || path.empty() ||
!rect.Contains(Bounds(path))) return PathsD();
CheckPrecision(precision);
const double scale = std::pow(10, precision);
Rect64 r = ScaleRect<int64_t, double>(rect, scale);
class RectClipLines rcl(r);
Path64 p = ScalePath<int64_t, double>(path, scale);
return ScalePaths<double, int64_t>(rcl.Execute(p), 1 / scale);
}
inline PathsD RectClipLines(const RectD& rect, const PathsD& paths, int precision = 2)
{
PathsD result;
if (rect.IsEmpty() || paths.empty()) return result;
CheckPrecision(precision);
const double scale = std::pow(10, precision);
Rect64 r = ScaleRect<int64_t, double>(rect, scale);
class RectClipLines rcl(r);
result.reserve(paths.size());
for (const PathD& path : paths)
{
RectD pathRec = Bounds(path);
if (!rect.Intersects(pathRec))
continue;
else if (rect.Contains(pathRec))
result.push_back(path);
else
{
Path64 p = ScalePath<int64_t, double>(path, scale);
Paths64 pp = rcl.Execute(p);
if (pp.empty()) continue;
PathsD ppd = ScalePaths<double, int64_t>(pp, 1 / scale);
result.insert(result.end(), ppd.begin(), ppd.end());
}
}
return result;
}
namespace details
{
inline void PolyPathToPaths64(const PolyPath64& polypath, Paths64& paths)
{
paths.push_back(polypath.Polygon());
for (const auto& child : polypath)
PolyPathToPaths64(*child, paths);
}
inline void PolyPathToPathsD(const PolyPathD& polypath, PathsD& paths)
{
paths.push_back(polypath.Polygon());
for (const auto& child : polypath)
PolyPathToPathsD(*child, paths);
}
inline bool PolyPath64ContainsChildren(const PolyPath64& pp)
{
for (const auto& child : pp)
{
// return false if this child isn't fully contained by its parent
// the following algorithm is a bit too crude, and doesn't account
// for rounding errors. A better algorithm is to return false when
// consecutive vertices are found outside the parent's polygon.
//const Path64& path = pp.Polygon();
//if (std::any_of(child->Polygon().cbegin(), child->Polygon().cend(),
// [path](const auto& pt) {return (PointInPolygon(pt, path) ==
// PointInPolygonResult::IsOutside); })) return false;
int outsideCnt = 0;
for (const Point64& pt : child->Polygon())
{
PointInPolygonResult result = PointInPolygon(pt, pp.Polygon());
if (result == PointInPolygonResult::IsInside) --outsideCnt;
else if (result == PointInPolygonResult::IsOutside) ++outsideCnt;
if (outsideCnt > 1) return false;
else if (outsideCnt < -1) break;
}
// now check any nested children too
if (child->Count() > 0 && !PolyPath64ContainsChildren(*child))
return false;
}
return true;
}
inline bool GetInt(std::string::const_iterator& iter, const
std::string::const_iterator& end_iter, int64_t& val)
{
val = 0;
bool is_neg = *iter == '-';
if (is_neg) ++iter;
std::string::const_iterator start_iter = iter;
while (iter != end_iter &&
((*iter >= '0') && (*iter <= '9')))
{
val = val * 10 + (static_cast<int64_t>(*iter++) - '0');
}
if (is_neg) val = -val;
return (iter != start_iter);
}
inline bool GetFloat(std::string::const_iterator& iter, const
std::string::const_iterator& end_iter, double& val)
{
val = 0;
bool is_neg = *iter == '-';
if (is_neg) ++iter;
int dec_pos = 1;
const std::string::const_iterator start_iter = iter;
while (iter != end_iter && (*iter == '.' ||
((*iter >= '0') && (*iter <= '9'))))
{
if (*iter == '.')
{
if (dec_pos != 1) break;
dec_pos = 0;
++iter;
continue;
}
if (dec_pos != 1) --dec_pos;
val = val * 10 + ((int64_t)(*iter++) - '0');
}
if (iter == start_iter || dec_pos == 0) return false;
if (dec_pos < 0)
val *= std::pow(10, dec_pos);
if (is_neg)
val *= -1;
return true;
}
inline void SkipWhiteSpace(std::string::const_iterator& iter,
const std::string::const_iterator& end_iter)
{
while (iter != end_iter && *iter <= ' ') ++iter;
}
inline void SkipSpacesWithOptionalComma(std::string::const_iterator& iter,
const std::string::const_iterator& end_iter)
{
bool comma_seen = false;
while (iter != end_iter)
{
if (*iter == ' ') ++iter;
else if (*iter == ',')
{
if (comma_seen) return; // don't skip 2 commas!
comma_seen = true;
++iter;
}
else return;
}
}
inline bool has_one_match(const char c, char* chrs)
{
while (*chrs > 0 && c != *chrs) ++chrs;
if (!*chrs) return false;
*chrs = ' '; // only match once per char
return true;
}
inline void SkipUserDefinedChars(std::string::const_iterator& iter,
const std::string::const_iterator& end_iter, const std::string& skip_chars)
{
const size_t MAX_CHARS = 16;
char buff[MAX_CHARS] = {0};
std::copy(skip_chars.cbegin(), skip_chars.cend(), &buff[0]);
while (iter != end_iter &&
(*iter <= ' ' || has_one_match(*iter, buff))) ++iter;
return;
}
static void OutlinePolyPath(std::ostream& os,
bool isHole, size_t count, const std::string& preamble)
{
std::string plural = (count == 1) ? "." : "s.";
if (isHole)
{
if (count)
os << preamble << "+- Hole with " << count <<
" nested polygon" << plural << std::endl;
else
os << preamble << "+- Hole" << std::endl;
}
else
{
if (count)
os << preamble << "+- Polygon with " << count <<
" hole" << plural << std::endl;
else
os << preamble << "+- Polygon" << std::endl;
}
}
static void OutlinePolyPath64(std::ostream& os, const PolyPath64& pp,
std::string preamble, bool last_child)
{
OutlinePolyPath(os, pp.IsHole(), pp.Count(), preamble);
preamble += (!last_child) ? "| " : " ";
if (pp.Count())
{
PolyPath64List::const_iterator it = pp.begin();
for (; it < pp.end() - 1; ++it)
OutlinePolyPath64(os, **it, preamble, false);
OutlinePolyPath64(os, **it, preamble, true);
}
}
static void OutlinePolyPathD(std::ostream& os, const PolyPathD& pp,
std::string preamble, bool last_child)
{
OutlinePolyPath(os, pp.IsHole(), pp.Count(), preamble);
preamble += (!last_child) ? "| " : " ";
if (pp.Count())
{
PolyPathDList::const_iterator it = pp.begin();
for (; it < pp.end() - 1; ++it)
OutlinePolyPathD(os, **it, preamble, false);
OutlinePolyPathD(os, **it, preamble, true);
}
}
} // end details namespace
inline std::ostream& operator<< (std::ostream& os, const PolyTree64& pp)
{
PolyPath64List::const_iterator it = pp.begin();
for (; it < pp.end() - 1; ++it)
details::OutlinePolyPath64(os, **it, " ", false);
details::OutlinePolyPath64(os, **it, " ", true);
os << std::endl << std::endl;
if (!pp.Level()) os << std::endl;
return os;
}
inline std::ostream& operator<< (std::ostream& os, const PolyTreeD& pp)
{
PolyPathDList::const_iterator it = pp.begin();
for (; it < pp.end() - 1; ++it)
details::OutlinePolyPathD(os, **it, " ", false);
details::OutlinePolyPathD(os, **it, " ", true);
os << std::endl << std::endl;
if (!pp.Level()) os << std::endl;
return os;
}
inline Paths64 PolyTreeToPaths64(const PolyTree64& polytree)
{
Paths64 result;
for (const auto& child : polytree)
details::PolyPathToPaths64(*child, result);
return result;
}
inline PathsD PolyTreeToPathsD(const PolyTreeD& polytree)
{
PathsD result;
for (const auto& child : polytree)
details::PolyPathToPathsD(*child, result);
return result;
}
inline bool CheckPolytreeFullyContainsChildren(const PolyTree64& polytree)
{
for (const auto& child : polytree)
if (child->Count() > 0 &&
!details::PolyPath64ContainsChildren(*child))
return false;
return true;
}
inline Path64 MakePath(const std::string& s)
{
const std::string skip_chars = " ,(){}[]";
Path64 result;
std::string::const_iterator s_iter = s.cbegin();
details::SkipUserDefinedChars(s_iter, s.cend(), skip_chars);
while (s_iter != s.cend())
{
int64_t y = 0, x = 0;
if (!details::GetInt(s_iter, s.cend(), x)) break;
details::SkipSpacesWithOptionalComma(s_iter, s.cend());
if (!details::GetInt(s_iter, s.cend(), y)) break;
result.push_back(Point64(x, y));
details::SkipUserDefinedChars(s_iter, s.cend(), skip_chars);
}
return result;
}
inline PathD MakePathD(const std::string& s)
{
const std::string skip_chars = " ,(){}[]";
PathD result;
std::string::const_iterator s_iter = s.cbegin();
details::SkipUserDefinedChars(s_iter, s.cend(), skip_chars);
while (s_iter != s.cend())
{
double y = 0, x = 0;
if (!details::GetFloat(s_iter, s.cend(), x)) break;
details::SkipSpacesWithOptionalComma(s_iter, s.cend());
if (!details::GetFloat(s_iter, s.cend(), y)) break;
result.push_back(PointD(x, y));
details::SkipUserDefinedChars(s_iter, s.cend(), skip_chars);
}
return result;
}
inline Path64 TrimCollinear(const Path64& p, bool is_open_path = false)
{
size_t len = p.size();
if (len < 3)
{
if (!is_open_path || len < 2 || p[0] == p[1]) return Path64();
else return p;
}
Path64 dst;
dst.reserve(len);
Path64::const_iterator srcIt = p.cbegin(), prevIt, stop = p.cend() - 1;
if (!is_open_path)
{
while (srcIt != stop && !CrossProduct(*stop, *srcIt, *(srcIt + 1)))
++srcIt;
while (srcIt != stop && !CrossProduct(*(stop - 1), *stop, *srcIt))
--stop;
if (srcIt == stop) return Path64();
}
prevIt = srcIt++;
dst.push_back(*prevIt);
for (; srcIt != stop; ++srcIt)
{
if (CrossProduct(*prevIt, *srcIt, *(srcIt + 1)))
{
prevIt = srcIt;
dst.push_back(*prevIt);
}
}
if (is_open_path)
dst.push_back(*srcIt);
else if (CrossProduct(*prevIt, *stop, dst[0]))
dst.push_back(*stop);
else
{
while (dst.size() > 2 &&
!CrossProduct(dst[dst.size() - 1], dst[dst.size() - 2], dst[0]))
dst.pop_back();
if (dst.size() < 3) return Path64();
}
return dst;
}
inline PathD TrimCollinear(const PathD& path, int precision, bool is_open_path = false)
{
CheckPrecision(precision);
const double scale = std::pow(10, precision);
Path64 p = ScalePath<int64_t, double>(path, scale);
p = TrimCollinear(p, is_open_path);
return ScalePath<double, int64_t>(p, 1/scale);
}
template <typename T>
inline double Distance(const Point<T> pt1, const Point<T> pt2)
{
return std::sqrt(DistanceSqr(pt1, pt2));
}
template <typename T>
inline double Length(const Path<T>& path, bool is_closed_path = false)
{
double result = 0.0;
if (path.size() < 2) return result;
auto it = path.cbegin(), stop = path.end() - 1;
for (; it != stop; ++it)
result += Distance(*it, *(it + 1));
if (is_closed_path)
result += Distance(*stop, *path.cbegin());
return result;
}
template <typename T>
inline bool NearCollinear(const Point<T>& pt1, const Point<T>& pt2, const Point<T>& pt3, double sin_sqrd_min_angle_rads)
{
double cp = std::abs(CrossProduct(pt1, pt2, pt3));
return (cp * cp) / (DistanceSqr(pt1, pt2) * DistanceSqr(pt2, pt3)) < sin_sqrd_min_angle_rads;
}
template <typename T>
inline Path<T> Ellipse(const Rect<T>& rect, int steps = 0)
{
return Ellipse(rect.MidPoint(),
static_cast<double>(rect.Width()) *0.5,
static_cast<double>(rect.Height()) * 0.5, steps);
}
template <typename T>
inline Path<T> Ellipse(const Point<T>& center,
double radiusX, double radiusY = 0, int steps = 0)
{
if (radiusX <= 0) return Path<T>();
if (radiusY <= 0) radiusY = radiusX;
if (steps <= 2)
steps = static_cast<int>(PI * sqrt((radiusX + radiusY) / 2));
double si = std::sin(2 * PI / steps);
double co = std::cos(2 * PI / steps);
double dx = co, dy = si;
Path<T> result;
result.reserve(steps);
result.push_back(Point<T>(center.x + radiusX, static_cast<double>(center.y)));
for (int i = 1; i < steps; ++i)
{
result.push_back(Point<T>(center.x + radiusX * dx, center.y + radiusY * dy));
double x = dx * co - dy * si;
dy = dy * co + dx * si;
dx = x;
}
return result;
}
template <typename T>
inline double PerpendicDistFromLineSqrd(const Point<T>& pt,
const Point<T>& line1, const Point<T>& line2)
{
double a = static_cast<double>(pt.x - line1.x);
double b = static_cast<double>(pt.y - line1.y);
double c = static_cast<double>(line2.x - line1.x);
double d = static_cast<double>(line2.y - line1.y);
if (c == 0 && d == 0) return 0;
return Sqr(a * d - c * b) / (c * c + d * d);
}
inline size_t GetNext(size_t current, size_t high,
const std::vector<bool>& flags)
{
++current;
while (current <= high && flags[current]) ++current;
if (current <= high) return current;
current = 0;
while (flags[current]) ++current;
return current;
}
inline size_t GetPrior(size_t current, size_t high,
const std::vector<bool>& flags)
{
if (current == 0) current = high;
else --current;
while (current > 0 && flags[current]) --current;
if (!flags[current]) return current;
current = high;
while (flags[current]) --current;
return current;
}
template <typename T>
inline Path<T> SimplifyPath(const Path<T> path,
double epsilon, bool isOpenPath = false)
{
const size_t len = path.size(), high = len -1;
const double epsSqr = Sqr(epsilon);
if (len < 4) return Path<T>(path);
std::vector<bool> flags(len);
std::vector<double> distSqr(len);
size_t prior = high, curr = 0, start, next, prior2, next2;
if (isOpenPath)
{
distSqr[0] = MAX_DBL;
distSqr[high] = MAX_DBL;
}
else
{
distSqr[0] = PerpendicDistFromLineSqrd(path[0], path[high], path[1]);
distSqr[high] = PerpendicDistFromLineSqrd(path[high], path[0], path[high - 1]);
}
for (size_t i = 1; i < high; ++i)
distSqr[i] = PerpendicDistFromLineSqrd(path[i], path[i - 1], path[i + 1]);
for (;;)
{
if (distSqr[curr] > epsSqr)
{
start = curr;
do
{
curr = GetNext(curr, high, flags);
} while (curr != start && distSqr[curr] > epsSqr);
if (curr == start) break;
}
prior = GetPrior(curr, high, flags);
next = GetNext(curr, high, flags);
if (next == prior) break;
if (distSqr[next] < distSqr[curr])
{
flags[next] = true;
next = GetNext(next, high, flags);
next2 = GetNext(next, high, flags);
distSqr[curr] = PerpendicDistFromLineSqrd(path[curr], path[prior], path[next]);
if (next != high || !isOpenPath)
distSqr[next] = PerpendicDistFromLineSqrd(path[next], path[curr], path[next2]);
curr = next;
}
else
{
flags[curr] = true;
curr = next;
next = GetNext(next, high, flags);
prior2 = GetPrior(prior, high, flags);
distSqr[curr] = PerpendicDistFromLineSqrd(path[curr], path[prior], path[next]);
if (prior != 0 || !isOpenPath)
distSqr[prior] = PerpendicDistFromLineSqrd(path[prior], path[prior2], path[curr]);
}
}
Path<T> result;
result.reserve(len);
for (typename Path<T>::size_type i = 0; i < len; ++i)
if (!flags[i]) result.push_back(path[i]);
return result;
}
template <typename T>
inline Paths<T> SimplifyPaths(const Paths<T> paths,
double epsilon, bool isOpenPath = false)
{
Paths<T> result;
result.reserve(paths.size());
for (const auto& path : paths)
result.push_back(SimplifyPath(path, epsilon, isOpenPath));
return result;
}
template <typename T>
inline void RDP(const Path<T> path, std::size_t begin,
std::size_t end, double epsSqrd, std::vector<bool>& flags)
{
typename Path<T>::size_type idx = 0;
double max_d = 0;
while (end > begin && path[begin] == path[end]) flags[end--] = false;
for (typename Path<T>::size_type i = begin + 1; i < end; ++i)
{
// PerpendicDistFromLineSqrd - avoids expensive Sqrt()
double d = PerpendicDistFromLineSqrd(path[i], path[begin], path[end]);
if (d <= max_d) continue;
max_d = d;
idx = i;
}
if (max_d <= epsSqrd) return;
flags[idx] = true;
if (idx > begin + 1) RDP(path, begin, idx, epsSqrd, flags);
if (idx < end - 1) RDP(path, idx, end, epsSqrd, flags);
}
template <typename T>
inline Path<T> RamerDouglasPeucker(const Path<T>& path, double epsilon)
{
const typename Path<T>::size_type len = path.size();
if (len < 5) return Path<T>(path);
std::vector<bool> flags(len);
flags[0] = true;
flags[len - 1] = true;
RDP(path, 0, len - 1, Sqr(epsilon), flags);
Path<T> result;
result.reserve(len);
for (typename Path<T>::size_type i = 0; i < len; ++i)
if (flags[i])
result.push_back(path[i]);
return result;
}
template <typename T>
inline Paths<T> RamerDouglasPeucker(const Paths<T>& paths, double epsilon)
{
Paths<T> result;
result.reserve(paths.size());
std::transform(paths.begin(), paths.end(), back_inserter(result),
[epsilon](const auto& path)
{ return RamerDouglasPeucker<T>(path, epsilon); });
return result;
}
} // end Clipper2Lib namespace
#endif // CLIPPER_H
Reference in New Issue View Git Blame Copy Permalink