mirror of https://github.com/axmolengine/axmol.git
503 lines
16 KiB
C++
503 lines
16 KiB
C++
/*******************************************************************************
|
|
* Author : Angus Johnson *
|
|
* Version : Clipper2 - ver.1.0.4 *
|
|
* Date : 4 September 2022 *
|
|
* Website : http://www.angusj.com *
|
|
* Copyright : Angus Johnson 2010-2022 *
|
|
* Purpose : This is the main polygon clipping module *
|
|
* License : http://www.boost.org/LICENSE_1_0.txt *
|
|
*******************************************************************************/
|
|
|
|
#ifndef clipper_engine_h
|
|
#define clipper_engine_h
|
|
|
|
#define CLIPPER2_VERSION "1.0.0"
|
|
|
|
#include <cstdlib>
|
|
#include <queue>
|
|
#include <stdexcept>
|
|
#include <vector>
|
|
#include <functional>
|
|
#include "clipper.core.h"
|
|
|
|
namespace Clipper2Lib {
|
|
|
|
struct Scanline;
|
|
struct IntersectNode;
|
|
struct Active;
|
|
struct Vertex;
|
|
struct LocalMinima;
|
|
struct OutRec;
|
|
struct Joiner;
|
|
|
|
//Note: all clipping operations except for Difference are commutative.
|
|
enum class ClipType { None, Intersection, Union, Difference, Xor };
|
|
|
|
enum class PathType { Subject, Clip };
|
|
|
|
enum class VertexFlags : uint32_t {
|
|
None = 0, OpenStart = 1, OpenEnd = 2, LocalMax = 4, LocalMin = 8
|
|
};
|
|
|
|
constexpr enum VertexFlags operator &(enum VertexFlags a, enum VertexFlags b)
|
|
{
|
|
return (enum VertexFlags)(uint32_t(a) & uint32_t(b));
|
|
}
|
|
|
|
constexpr enum VertexFlags operator |(enum VertexFlags a, enum VertexFlags b)
|
|
{
|
|
return (enum VertexFlags)(uint32_t(a) | uint32_t(b));
|
|
}
|
|
|
|
struct Vertex {
|
|
Point64 pt;
|
|
Vertex* next = nullptr;
|
|
Vertex* prev = nullptr;
|
|
VertexFlags flags = VertexFlags::None;
|
|
};
|
|
|
|
struct OutPt {
|
|
Point64 pt;
|
|
OutPt* next = nullptr;
|
|
OutPt* prev = nullptr;
|
|
OutRec* outrec;
|
|
Joiner* joiner = nullptr;
|
|
|
|
OutPt(const Point64& pt_, OutRec* outrec_): pt(pt_), outrec(outrec_) {
|
|
next = this;
|
|
prev = this;
|
|
}
|
|
};
|
|
|
|
template <typename T>
|
|
class PolyPath;
|
|
|
|
using PolyPath64 = PolyPath<int64_t>;
|
|
using PolyPathD = PolyPath<double>;
|
|
|
|
template <typename T>
|
|
using PolyTree = PolyPath<T>;
|
|
using PolyTree64 = PolyTree<int64_t>;
|
|
using PolyTreeD = PolyTree<double>;
|
|
|
|
struct OutRec;
|
|
typedef std::vector<OutRec*> OutRecList;
|
|
|
|
//OutRec: contains a path in the clipping solution. Edges in the AEL will
|
|
//have OutRec pointers assigned when they form part of the clipping solution.
|
|
struct OutRec {
|
|
size_t idx = 0;
|
|
OutRec* owner = nullptr;
|
|
OutRecList* splits = nullptr;
|
|
Active* front_edge = nullptr;
|
|
Active* back_edge = nullptr;
|
|
OutPt* pts = nullptr;
|
|
PolyPath64* polypath = nullptr;
|
|
Rect64 bounds = {};
|
|
Path64 path;
|
|
bool is_open = false;
|
|
~OutRec() { if (splits) delete splits; };
|
|
};
|
|
|
|
///////////////////////////////////////////////////////////////////
|
|
//Important: UP and DOWN here are premised on Y-axis positive down
|
|
//displays, which is the orientation used in Clipper's development.
|
|
///////////////////////////////////////////////////////////////////
|
|
|
|
struct Active {
|
|
Point64 bot;
|
|
Point64 top;
|
|
int64_t curr_x = 0; //current (updated at every new scanline)
|
|
double dx = 0.0;
|
|
int wind_dx = 1; //1 or -1 depending on winding direction
|
|
int wind_cnt = 0;
|
|
int wind_cnt2 = 0; //winding count of the opposite polytype
|
|
OutRec* outrec = nullptr;
|
|
//AEL: 'active edge list' (Vatti's AET - active edge table)
|
|
// a linked list of all edges (from left to right) that are present
|
|
// (or 'active') within the current scanbeam (a horizontal 'beam' that
|
|
// sweeps from bottom to top over the paths in the clipping operation).
|
|
Active* prev_in_ael = nullptr;
|
|
Active* next_in_ael = nullptr;
|
|
//SEL: 'sorted edge list' (Vatti's ST - sorted table)
|
|
// linked list used when sorting edges into their new positions at the
|
|
// top of scanbeams, but also (re)used to process horizontals.
|
|
Active* prev_in_sel = nullptr;
|
|
Active* next_in_sel = nullptr;
|
|
Active* jump = nullptr;
|
|
Vertex* vertex_top = nullptr;
|
|
LocalMinima* local_min = nullptr; // the bottom of an edge 'bound' (also Vatti)
|
|
bool is_left_bound = false;
|
|
};
|
|
|
|
struct LocalMinima {
|
|
Vertex* vertex;
|
|
PathType polytype;
|
|
bool is_open;
|
|
LocalMinima(Vertex* v, PathType pt, bool open) :
|
|
vertex(v), polytype(pt), is_open(open){}
|
|
};
|
|
|
|
struct IntersectNode {
|
|
Point64 pt;
|
|
Active* edge1;
|
|
Active* edge2;
|
|
IntersectNode() : pt(Point64(0, 0)), edge1(NULL), edge2(NULL) {}
|
|
IntersectNode(Active* e1, Active* e2, Point64& pt_) :
|
|
pt(pt_), edge1(e1), edge2(e2)
|
|
{
|
|
}
|
|
};
|
|
|
|
#ifdef USINGZ
|
|
typedef std::function<void(const Point64& e1bot, const Point64& e1top,
|
|
const Point64& e2bot, const Point64& e2top, Point64& pt)> ZCallback64;
|
|
|
|
typedef std::function<void(const PointD& e1bot, const PointD& e1top,
|
|
const PointD& e2bot, const PointD& e2top, PointD& pt)> ZCallbackD;
|
|
#endif
|
|
|
|
// ClipperBase -------------------------------------------------------------
|
|
|
|
class ClipperBase {
|
|
private:
|
|
ClipType cliptype_ = ClipType::None;
|
|
FillRule fillrule_ = FillRule::EvenOdd;
|
|
FillRule fillpos = FillRule::Positive;
|
|
int64_t bot_y_ = 0;
|
|
bool has_open_paths_ = false;
|
|
bool minima_list_sorted_ = false;
|
|
bool using_polytree_ = false;
|
|
bool succeeded_ = true;
|
|
Active *actives_ = nullptr;
|
|
Active *sel_ = nullptr;
|
|
Joiner *horz_joiners_ = nullptr;
|
|
std::vector<LocalMinima*> minima_list_; //pointers in case of memory reallocs
|
|
std::vector<LocalMinima*>::iterator current_locmin_iter_;
|
|
std::vector<Vertex*> vertex_lists_;
|
|
std::priority_queue<int64_t> scanline_list_;
|
|
std::vector<IntersectNode> intersect_nodes_;
|
|
std::vector<OutRec*> outrec_list_; //pointers in case of memory reallocs
|
|
std::vector<Joiner*> joiner_list_; //pointers in case of memory reallocs
|
|
void Reset();
|
|
void InsertScanline(int64_t y);
|
|
bool PopScanline(int64_t &y);
|
|
bool PopLocalMinima(int64_t y, LocalMinima *&local_minima);
|
|
void DisposeAllOutRecs();
|
|
void DisposeVerticesAndLocalMinima();
|
|
void AddLocMin(Vertex &vert, PathType polytype, bool is_open);
|
|
bool IsContributingClosed(const Active &e) const;
|
|
inline bool IsContributingOpen(const Active &e) const;
|
|
void SetWindCountForClosedPathEdge(Active &edge);
|
|
void SetWindCountForOpenPathEdge(Active &e);
|
|
void InsertLocalMinimaIntoAEL(int64_t bot_y);
|
|
void InsertLeftEdge(Active &e);
|
|
inline void PushHorz(Active &e);
|
|
inline bool PopHorz(Active *&e);
|
|
inline OutPt* StartOpenPath(Active &e, const Point64& pt);
|
|
inline void UpdateEdgeIntoAEL(Active *e);
|
|
OutPt* IntersectEdges(Active &e1, Active &e2, const Point64& pt);
|
|
inline void DeleteFromAEL(Active &e);
|
|
inline void AdjustCurrXAndCopyToSEL(const int64_t top_y);
|
|
void DoIntersections(const int64_t top_y);
|
|
void AddNewIntersectNode(Active &e1, Active &e2, const int64_t top_y);
|
|
bool BuildIntersectList(const int64_t top_y);
|
|
void ProcessIntersectList();
|
|
void SwapPositionsInAEL(Active& edge1, Active& edge2);
|
|
OutPt* AddOutPt(const Active &e, const Point64& pt);
|
|
OutPt* AddLocalMinPoly(Active &e1, Active &e2,
|
|
const Point64& pt, bool is_new = false);
|
|
OutPt* AddLocalMaxPoly(Active &e1, Active &e2, const Point64& pt);
|
|
void DoHorizontal(Active &horz);
|
|
bool ResetHorzDirection(const Active &horz, const Active *max_pair,
|
|
int64_t &horz_left, int64_t &horz_right);
|
|
void DoTopOfScanbeam(const int64_t top_y);
|
|
Active *DoMaxima(Active &e);
|
|
void JoinOutrecPaths(Active &e1, Active &e2);
|
|
void CompleteSplit(OutPt* op1, OutPt* op2, OutRec& outrec);
|
|
bool ValidateClosedPathEx(OutPt*& outrec);
|
|
void CleanCollinear(OutRec* outrec);
|
|
void FixSelfIntersects(OutRec* outrec);
|
|
OutPt* DoSplitOp(OutPt* outRecOp, OutPt* splitOp);
|
|
Joiner* GetHorzTrialParent(const OutPt* op);
|
|
bool OutPtInTrialHorzList(OutPt* op);
|
|
void SafeDisposeOutPts(OutPt*& op);
|
|
void SafeDeleteOutPtJoiners(OutPt* op);
|
|
void AddTrialHorzJoin(OutPt* op);
|
|
void DeleteTrialHorzJoin(OutPt* op);
|
|
void ConvertHorzTrialsToJoins();
|
|
void AddJoin(OutPt* op1, OutPt* op2);
|
|
void DeleteJoin(Joiner* joiner);
|
|
void ProcessJoinerList();
|
|
OutRec* ProcessJoin(Joiner* joiner);
|
|
bool ExecuteInternal(ClipType ct, FillRule ft, bool use_polytrees);
|
|
bool DeepCheckOwner(OutRec* outrec, OutRec* owner);
|
|
void BuildPaths(Paths64& solutionClosed, Paths64* solutionOpen);
|
|
void BuildTree(PolyPath64& polytree, Paths64& open_paths);
|
|
protected:
|
|
#ifdef USINGZ
|
|
ZCallback64 zCallback_ = nullptr;
|
|
void SetZ(const Active& e1, const Active& e2, Point64& pt);
|
|
#endif
|
|
void CleanUp(); // unlike Clear, CleanUp preserves added paths
|
|
void AddPath(const Path64& path, PathType polytype, bool is_open);
|
|
void AddPaths(const Paths64& paths, PathType polytype, bool is_open);
|
|
|
|
bool Execute(ClipType clip_type,
|
|
FillRule fill_rule, Paths64& solution_closed);
|
|
bool Execute(ClipType clip_type,
|
|
FillRule fill_rule, Paths64& solution_closed, Paths64& solution_open);
|
|
bool Execute(ClipType clip_type, FillRule fill_rule, PolyTree64& polytree);
|
|
bool Execute(ClipType clip_type,
|
|
FillRule fill_rule, PolyTree64& polytree, Paths64& open_paths);
|
|
public:
|
|
virtual ~ClipperBase();
|
|
bool PreserveCollinear = true;
|
|
bool ReverseSolution = false;
|
|
void Clear();
|
|
};
|
|
|
|
// PolyPath / PolyTree --------------------------------------------------------
|
|
|
|
//PolyTree: is intended as a READ-ONLY data structure for CLOSED paths returned
|
|
//by clipping operations. While this structure is more complex than the
|
|
//alternative Paths structure, it does preserve path 'ownership' - ie those
|
|
//paths that contain (or own) other paths. This will be useful to some users.
|
|
|
|
template <typename T>
|
|
class PolyPath final {
|
|
private:
|
|
double scale_;
|
|
Path<T> polygon_;
|
|
std::vector<PolyPath*> childs_;
|
|
protected:
|
|
const PolyPath<T>* parent_;
|
|
PolyPath(const PolyPath<T>* parent,
|
|
const Path<T>& path) :
|
|
scale_(parent->scale_), polygon_(path), parent_(parent){}
|
|
public:
|
|
|
|
explicit PolyPath(int precision = 0) // NB only for root node
|
|
{
|
|
scale_ = std::pow(10, precision);
|
|
parent_ = nullptr;
|
|
}
|
|
|
|
~PolyPath() { Clear(); };
|
|
|
|
//https://en.cppreference.com/w/cpp/language/rule_of_three
|
|
PolyPath(const PolyPath&) = delete;
|
|
PolyPath& operator=(const PolyPath&) = delete;
|
|
|
|
PolyPath<T>* operator [] (size_t index) { return childs_[index]; }
|
|
|
|
typename std::vector<PolyPath*>::const_iterator begin() const { return childs_.cbegin(); }
|
|
typename std::vector<PolyPath*>::const_iterator end() const { return childs_.cend(); }
|
|
|
|
void Clear() {
|
|
for (PolyPath<T>* child : childs_) delete child;
|
|
childs_.resize(0);
|
|
}
|
|
|
|
void reserve(size_t size)
|
|
{
|
|
if (size > childs_.size()) childs_.reserve(size);
|
|
}
|
|
|
|
PolyPath<T>* AddChild(const Path<T>& path)
|
|
{
|
|
childs_.push_back(new PolyPath<T>(this, path));
|
|
return childs_.back();
|
|
}
|
|
|
|
size_t Count() const { return childs_.size(); }
|
|
|
|
const PolyPath<T>* parent() const { return parent_; }
|
|
|
|
bool IsHole() const
|
|
{
|
|
const PolyPath* pp = parent_;
|
|
bool is_hole = pp;
|
|
while (pp) {
|
|
is_hole = !is_hole;
|
|
pp = pp->parent_;
|
|
}
|
|
return is_hole;
|
|
}
|
|
|
|
const Path<T>& Polygon() const { return polygon_; }
|
|
|
|
double Area() const
|
|
{
|
|
double result = Clipper2Lib::Area<T>(polygon_);
|
|
for (const PolyPath<T>* child : childs_)
|
|
result += child->Area();
|
|
return result;
|
|
}
|
|
|
|
};
|
|
|
|
|
|
void Polytree64ToPolytreeD(const PolyPath64& polytree, PolyPathD& result);
|
|
|
|
|
|
class Clipper64 : public ClipperBase
|
|
{
|
|
public:
|
|
#ifdef USINGZ
|
|
void SetZCallback(ZCallback64 cb) { zCallback_ = cb; }
|
|
#endif
|
|
|
|
void AddSubject(const Paths64& subjects)
|
|
{
|
|
AddPaths(subjects, PathType::Subject, false);
|
|
}
|
|
void AddOpenSubject(const Paths64& open_subjects)
|
|
{
|
|
AddPaths(open_subjects, PathType::Subject, true);
|
|
}
|
|
void AddClip(const Paths64& clips)
|
|
{
|
|
AddPaths(clips, PathType::Clip, false);
|
|
}
|
|
|
|
bool Execute(ClipType clip_type,
|
|
FillRule fill_rule, Paths64& closed_paths)
|
|
{
|
|
return ClipperBase::Execute(clip_type, fill_rule, closed_paths);
|
|
}
|
|
|
|
bool Execute(ClipType clip_type,
|
|
FillRule fill_rule, Paths64& closed_paths, Paths64& open_paths)
|
|
{
|
|
return ClipperBase::Execute(clip_type, fill_rule, closed_paths, open_paths);
|
|
}
|
|
|
|
bool Execute(ClipType clip_type, FillRule fill_rule, PolyTree64& polytree)
|
|
{
|
|
return ClipperBase::Execute(clip_type, fill_rule, polytree);
|
|
}
|
|
bool Execute(ClipType clip_type,
|
|
FillRule fill_rule, PolyTree64& polytree, Paths64& open_paths)
|
|
{
|
|
return ClipperBase::Execute(clip_type, fill_rule, polytree, open_paths);
|
|
}
|
|
};
|
|
|
|
class ClipperD : public ClipperBase {
|
|
private:
|
|
double scale_ = 1.0, invScale_ = 1.0;
|
|
#ifdef USINGZ
|
|
ZCallbackD zCallback_ = nullptr;
|
|
#endif
|
|
public:
|
|
explicit ClipperD(int precision = 2) : ClipperBase()
|
|
{
|
|
scale_ = std::pow(10, precision);
|
|
invScale_ = 1 / scale_;
|
|
}
|
|
|
|
#ifdef USINGZ
|
|
void SetZCallback(ZCallbackD cb) { zCallback_ = cb; };
|
|
|
|
void ZCB(const Point64& e1bot, const Point64& e1top,
|
|
const Point64& e2bot, const Point64& e2top, Point64& pt)
|
|
{
|
|
// de-scale (x & y)
|
|
// temporarily convert integers to their initial float values
|
|
// this will slow clipping marginally but will make it much easier
|
|
// to understand the coordinates passed to the callback function
|
|
PointD tmp = PointD(pt) * invScale_;
|
|
PointD e1b = PointD(e1bot) * invScale_;
|
|
PointD e1t = PointD(e1top) * invScale_;
|
|
PointD e2b = PointD(e2bot) * invScale_;
|
|
PointD e2t = PointD(e2top) * invScale_;
|
|
zCallback_(e1b,e1t, e2b, e2t, tmp);
|
|
pt.z = tmp.z; // only update 'z'
|
|
};
|
|
|
|
void CheckCallback()
|
|
{
|
|
if(zCallback_)
|
|
// if the user defined float point callback has been assigned
|
|
// then assign the proxy callback function
|
|
ClipperBase::zCallback_ =
|
|
std::bind(&ClipperD::ZCB, this, std::placeholders::_1,
|
|
std::placeholders::_2, std::placeholders::_3,
|
|
std::placeholders::_4, std::placeholders::_5);
|
|
else
|
|
ClipperBase::zCallback_ = nullptr;
|
|
}
|
|
|
|
#endif
|
|
|
|
void AddSubject(const PathsD& subjects)
|
|
{
|
|
AddPaths(ScalePaths<int64_t, double>(subjects, scale_), PathType::Subject, false);
|
|
}
|
|
|
|
void AddOpenSubject(const PathsD& open_subjects)
|
|
{
|
|
AddPaths(ScalePaths<int64_t, double>(open_subjects, scale_), PathType::Subject, true);
|
|
}
|
|
|
|
void AddClip(const PathsD& clips)
|
|
{
|
|
AddPaths(ScalePaths<int64_t, double>(clips, scale_), PathType::Clip, false);
|
|
}
|
|
|
|
bool Execute(ClipType clip_type, FillRule fill_rule, PathsD& closed_paths)
|
|
{
|
|
#ifdef USINGZ
|
|
CheckCallback();
|
|
#endif
|
|
Paths64 closed_paths64;
|
|
if (!ClipperBase::Execute(clip_type, fill_rule, closed_paths64)) return false;
|
|
closed_paths = ScalePaths<double, int64_t>(closed_paths64, invScale_);
|
|
return true;
|
|
}
|
|
|
|
bool Execute(ClipType clip_type,
|
|
FillRule fill_rule, PathsD& closed_paths, PathsD& open_paths)
|
|
{
|
|
#ifdef USINGZ
|
|
CheckCallback();
|
|
#endif
|
|
Paths64 closed_paths64;
|
|
Paths64 open_paths64;
|
|
if (!ClipperBase::Execute(clip_type,
|
|
fill_rule, closed_paths64, open_paths64)) return false;
|
|
closed_paths = ScalePaths<double, int64_t>(closed_paths64, invScale_);
|
|
open_paths = ScalePaths<double, int64_t>(open_paths64, invScale_);
|
|
return true;
|
|
}
|
|
|
|
bool Execute(ClipType clip_type, FillRule fill_rule, PolyTreeD& polytree)
|
|
{
|
|
#ifdef USINGZ
|
|
CheckCallback();
|
|
#endif
|
|
PolyTree64 tree_result;
|
|
if (!ClipperBase::Execute(clip_type, fill_rule, tree_result)) return false;;
|
|
Polytree64ToPolytreeD(tree_result, polytree);
|
|
return true;
|
|
}
|
|
|
|
bool Execute(ClipType clip_type,
|
|
FillRule fill_rule, PolyTreeD& polytree, Paths64& open_paths)
|
|
{
|
|
#ifdef USINGZ
|
|
CheckCallback();
|
|
#endif
|
|
PolyTree64 tree_result;
|
|
if (!ClipperBase::Execute(clip_type, fill_rule, tree_result, open_paths)) return false;;
|
|
Polytree64ToPolytreeD(tree_result, polytree);
|
|
return true;
|
|
}
|
|
|
|
};
|
|
|
|
} // namespace
|
|
|
|
#endif // clipper_engine_h
|