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+// SPDX-License-Identifier: GPL-2.0-or-later
+/** @file
+ * TODO: insert short description here
+ *//*
+ * Authors: see git history
+ *
+ * Copyright (C) 2014 Authors
+ * Released under GNU GPL v2+, read the file 'COPYING' for more information.
+ */
+/*
+ * Path.h
+ * nlivarot
+ *
+ * Created by fred on Tue Jun 17 2003.
+ *
+ */
+
+#ifndef my_path
+#define my_path
+
+#include <vector>
+#include "LivarotDefs.h"
+#include <2geom/point.h>
+
+struct PathDescr;
+struct PathDescrLineTo;
+struct PathDescrArcTo;
+struct PathDescrCubicTo;
+struct PathDescrBezierTo;
+struct PathDescrIntermBezierTo;
+
+class SPStyle;
+
+/*
+ * the Path class: a structure to hold path description and their polyline approximation (not kept in sync)
+ * the path description is built with regular commands like MoveTo() LineTo(), etc
+ * the polyline approximation is built by a call to Convert() or its variants
+ * another possibility would be to call directly the AddPoint() functions, but that is not encouraged
+ * the conversion to polyline can salvage data as to where on the path each polyline's point lies; use
+ * ConvertWithBackData() for this. after this call, it's easy to rewind the polyline: sequences of points
+ * of the same path command can be reassembled in a command
+ */
+
+// polyline description commands
+enum
+{
+ polyline_lineto = 0, // a lineto
+ polyline_moveto = 1, // a moveto
+ polyline_forced = 2 // a forced point, ie a point that was an angle or an intersection in a previous life
+ // or more realistically a control point in the path description that created the polyline
+ // forced points are used as "breakable" points for the polyline -> cubic bezier patch operations
+ // each time the bezier fitter encounters such a point in the polyline, it decreases its treshhold,
+ // so that it is more likely to cut the polyline at that position and produce a bezier patch
+};
+
+class Shape;
+
+// path creation: 2 phases: first the path is given as a succession of commands (MoveTo, LineTo, CurveTo...); then it
+// is converted in a polyline
+// a polylone can be stroked or filled to make a polygon
+class Path
+{
+ friend class Shape;
+
+public:
+
+ // flags for the path construction
+ enum
+ {
+ descr_ready = 0,
+ descr_adding_bezier = 1, // we're making a bezier spline, so you can expect pending_bezier_* to have a value
+ descr_doing_subpath = 2, // we're doing a path, so there is a moveto somewhere
+ descr_delayed_bezier = 4,// the bezier spline we're doing was initiated by a TempBezierTo(), so we'll need an endpoint
+ descr_dirty = 16 // the path description was modified
+ };
+
+ // some data for the construction: what's pending, and some flags
+ int descr_flags;
+ int pending_bezier_cmd;
+ int pending_bezier_data;
+ int pending_moveto_cmd;
+ int pending_moveto_data;
+ // the path description
+ std::vector<PathDescr*> descr_cmd;
+
+ // polyline storage: a series of coordinates (and maybe weights)
+ // also back data: info on where this polyline's segment comes from, ie which command in the path description: "piece"
+ // and what abcissis on the chunk of path for this command: "t"
+ // t=0 means it's at the start of the command's chunk, t=1 it's at the end
+ struct path_lineto
+ {
+ path_lineto(bool m, Geom::Point pp) : isMoveTo(m), p(pp), piece(-1), t(0), closed(false) {}
+ path_lineto(bool m, Geom::Point pp, int pie, double tt) : isMoveTo(m), p(pp), piece(pie), t(tt), closed(false) {}
+
+ int isMoveTo;
+ Geom::Point p;
+ int piece;
+ double t;
+ bool closed; // true if subpath is closed (this point is the last point of a closed subpath)
+ };
+
+ std::vector<path_lineto> pts;
+
+ bool back;
+
+ Path();
+ virtual ~Path();
+
+ // creation of the path description
+ void Reset(); // reset to the empty description
+ void Copy (Path * who);
+
+ // the commands...
+ int ForcePoint();
+ int Close();
+ int MoveTo ( Geom::Point const &ip);
+ int LineTo ( Geom::Point const &ip);
+ int CubicTo ( Geom::Point const &ip, Geom::Point const &iStD, Geom::Point const &iEnD);
+ int ArcTo ( Geom::Point const &ip, double iRx, double iRy, double angle, bool iLargeArc, bool iClockwise);
+ int IntermBezierTo ( Geom::Point const &ip); // add a quadratic bezier spline control point
+ int BezierTo ( Geom::Point const &ip); // quadratic bezier spline to this point (control points can be added after this)
+ int TempBezierTo(); // start a quadratic bezier spline (control points can be added after this)
+ int EndBezierTo();
+ int EndBezierTo ( Geom::Point const &ip); // ends a quadratic bezier spline (for curves started with TempBezierTo)
+
+ // transforms a description in a polyline (for stroking and filling)
+ // treshhold is the max length^2 (sort of)
+ void Convert (double treshhold);
+ void ConvertEvenLines (double treshhold); // decomposes line segments too, for later recomposition
+ // same function for use when you want to later recompose the curves from the polyline
+ void ConvertWithBackData (double treshhold);
+
+ // creation of the polyline (you can tinker with these function if you want)
+ void SetBackData (bool nVal); // has back data?
+ void ResetPoints(); // resets to the empty polyline
+ int AddPoint ( Geom::Point const &iPt, bool mvto = false); // add point
+ int AddPoint ( Geom::Point const &iPt, int ip, double it, bool mvto = false);
+ int AddForcedPoint ( Geom::Point const &iPt); // add point
+ int AddForcedPoint ( Geom::Point const &iPt, int ip, double it);
+ int ReplacePoint(Geom::Point const &iPt); // replace point
+
+ // transform in a polygon (in a graph, in fact; a subsequent call to ConvertToShape is needed)
+ // - fills the polyline; justAdd=true doesn't reset the Shape dest, but simply adds the polyline into it
+ // closeIfNeeded=false prevent the function from closing the path (resulting in a non-eulerian graph
+ // pathID is a identification number for the path, and is used for recomposing curves from polylines
+ // give each different Path a different ID, and feed the appropriate orig[] to the ConvertToForme() function
+ void Fill(Shape *dest, int pathID = -1, bool justAdd = false,
+ bool closeIfNeeded = true, bool invert = false);
+
+ // - stroke the path; usual parameters: type of cap=butt, type of join=join and miter (see LivarotDefs.h)
+ // doClose treat the path as closed (ie a loop)
+ void Stroke(Shape *dest, bool doClose, double width, JoinType join,
+ ButtType butt, double miter, bool justAdd = false);
+
+ // build a Path that is the outline of the Path instance's description (the result is stored in dest)
+ // it doesn't compute the exact offset (it's way too complicated, but an approximation made of cubic bezier patches
+ // and segments. the algorithm was found in a plugin for Impress (by Chris Cox), but i can't find it back...
+ void Outline(Path *dest, double width, JoinType join, ButtType butt,
+ double miter);
+
+ // half outline with edges having the same direction as the original
+ void OutsideOutline(Path *dest, double width, JoinType join, ButtType butt,
+ double miter);
+
+ // half outline with edges having the opposite direction as the original
+ void InsideOutline (Path * dest, double width, JoinType join, ButtType butt,
+ double miter);
+
+ // polyline to cubic bezier patches
+ void Simplify (double treshhold);
+
+ // description simplification
+ void Coalesce (double tresh);
+
+ // utilities
+ // piece is a command no in the command list
+ // "at" is an abcissis on the path portion associated with this command
+ // 0=beginning of portion, 1=end of portion.
+ void PointAt (int piece, double at, Geom::Point & pos);
+ void PointAndTangentAt (int piece, double at, Geom::Point & pos, Geom::Point & tgt);
+
+ // last control point before the command i (i included)
+ // used when dealing with quadratic bezier spline, cause these can contain arbitrarily many commands
+ const Geom::Point PrevPoint (const int i) const;
+
+ // dash the polyline
+ // the result is stored in the polyline, so you lose the original. make a copy before if needed
+ void DashPolyline(float head,float tail,float body,int nbD,float *dashs,bool stPlain,float stOffset);
+
+ void DashPolylineFromStyle(SPStyle *style, float scale, float min_len);
+
+ //utilitaire pour inkscape
+ void LoadPath(Geom::Path const &path, Geom::Affine const &tr, bool doTransformation, bool append = false);
+ void LoadPathVector(Geom::PathVector const &pv, Geom::Affine const &tr, bool doTransformation);
+ void LoadPathVector(Geom::PathVector const &pv);
+ Geom::PathVector MakePathVector();
+
+ void Transform(const Geom::Affine &trans);
+
+ // decompose le chemin en ses sous-chemin
+ // killNoSurf=true -> oublie les chemins de surface nulle
+ Path** SubPaths(int &outNb,bool killNoSurf);
+ // pour recuperer les trous
+ // nbNest= nombre de contours
+ // conts= debut de chaque contour
+ // nesting= parent de chaque contour
+ Path** SubPathsWithNesting(int &outNb,bool killNoSurf,int nbNest,int* nesting,int* conts);
+ // surface du chemin (considere comme ferme)
+ double Surface();
+ void PolylineBoundingBox(double &l,double &t,double &r,double &b);
+ void FastBBox(double &l,double &t,double &r,double &b);
+ // longueur (totale des sous-chemins)
+ double Length();
+
+ void ConvertForcedToMoveTo();
+ void ConvertForcedToVoid();
+ struct cut_position {
+ int piece;
+ double t;
+ };
+ cut_position* CurvilignToPosition(int nbCv,double* cvAbs,int &nbCut);
+ cut_position PointToCurvilignPosition(Geom::Point const &pos, unsigned seg = 0) const;
+ //Should this take a cut_position as a param?
+ double PositionToLength(int piece, double t);
+
+ // caution: not tested on quadratic b-splines, most certainly buggy
+ void ConvertPositionsToMoveTo(int nbPos,cut_position* poss);
+ void ConvertPositionsToForced(int nbPos,cut_position* poss);
+
+ void Affiche();
+ char *svg_dump_path() const;
+
+ bool IsLineSegment(int piece);
+
+ private:
+ // utilitary functions for the path construction
+ void CancelBezier ();
+ void CloseSubpath();
+ void InsertMoveTo (Geom::Point const &iPt,int at);
+ void InsertForcePoint (int at);
+ void InsertLineTo (Geom::Point const &iPt,int at);
+ void InsertArcTo (Geom::Point const &ip, double iRx, double iRy, double angle, bool iLargeArc, bool iClockwise,int at);
+ void InsertCubicTo (Geom::Point const &ip, Geom::Point const &iStD, Geom::Point const &iEnD,int at);
+ void InsertBezierTo (Geom::Point const &iPt,int iNb,int at);
+ void InsertIntermBezierTo (Geom::Point const &iPt,int at);
+
+ // creation of dashes: take the polyline given by spP (length spL) and dash it according to head, body, etc. put the result in
+ // the polyline of this instance
+ void DashSubPath(int spL, int spP, std::vector<path_lineto> const &orig_pts, float head,float tail,float body,int nbD,float *dashs,bool stPlain,float stOffset);
+
+ // Functions used by the conversion.
+ // they append points to the polyline
+ void DoArc ( Geom::Point const &iS, Geom::Point const &iE, double rx, double ry,
+ double angle, bool large, bool wise, double tresh);
+ void RecCubicTo ( Geom::Point const &iS, Geom::Point const &iSd, Geom::Point const &iE, Geom::Point const &iEd, double tresh, int lev,
+ double maxL = -1.0);
+ void RecBezierTo ( Geom::Point const &iPt, Geom::Point const &iS, Geom::Point const &iE, double treshhold, int lev, double maxL = -1.0);
+
+ void DoArc ( Geom::Point const &iS, Geom::Point const &iE, double rx, double ry,
+ double angle, bool large, bool wise, double tresh, int piece);
+ void RecCubicTo ( Geom::Point const &iS, Geom::Point const &iSd, Geom::Point const &iE, Geom::Point const &iEd, double tresh, int lev,
+ double st, double et, int piece);
+ void RecBezierTo ( Geom::Point const &iPt, Geom::Point const &iS, const Geom::Point &iE, double treshhold, int lev, double st, double et,
+ int piece);
+
+ // don't pay attention
+ struct offset_orig
+ {
+ Path *orig;
+ int piece;
+ double tSt, tEn;
+ double off_dec;
+ };
+ void DoArc ( Geom::Point const &iS, Geom::Point const &iE, double rx, double ry,
+ double angle, bool large, bool wise, double tresh, int piece,
+ offset_orig & orig);
+ void RecCubicTo ( Geom::Point const &iS, Geom::Point const &iSd, Geom::Point const &iE, Geom::Point const &iEd, double tresh, int lev,
+ double st, double et, int piece, offset_orig & orig);
+ void RecBezierTo ( Geom::Point const &iPt, Geom::Point const &iS, Geom::Point const &iE, double treshhold, int lev, double st, double et,
+ int piece, offset_orig & orig);
+
+ static void ArcAngles ( Geom::Point const &iS, Geom::Point const &iE, double rx,
+ double ry, double angle, bool large, bool wise,
+ double &sang, double &eang);
+ static void QuadraticPoint (double t, Geom::Point &oPt, Geom::Point const &iS, Geom::Point const &iM, Geom::Point const &iE);
+ static void CubicTangent (double t, Geom::Point &oPt, Geom::Point const &iS,
+ Geom::Point const &iSd, Geom::Point const &iE,
+ Geom::Point const &iEd);
+
+ struct outline_callback_data
+ {
+ Path *orig;
+ int piece;
+ double tSt, tEn;
+ Path *dest;
+ double x1, y1, x2, y2;
+ union
+ {
+ struct
+ {
+ double dx1, dy1, dx2, dy2;
+ }
+ c;
+ struct
+ {
+ double mx, my;
+ }
+ b;
+ struct
+ {
+ double rx, ry, angle;
+ bool clock, large;
+ double stA, enA;
+ }
+ a;
+ }
+ d;
+ };
+
+ typedef void (outlineCallback) (outline_callback_data * data, double tol, double width);
+ struct outline_callbacks
+ {
+ outlineCallback *cubicto;
+ outlineCallback *bezierto;
+ outlineCallback *arcto;
+ };
+
+ void SubContractOutline (int off, int num_pd,
+ Path * dest, outline_callbacks & calls,
+ double tolerance, double width, JoinType join,
+ ButtType butt, double miter, bool closeIfNeeded,
+ bool skipMoveto, Geom::Point & lastP, Geom::Point & lastT);
+ void DoStroke(int off, int N, Shape *dest, bool doClose, double width, JoinType join,
+ ButtType butt, double miter, bool justAdd = false);
+
+ static void TangentOnSegAt(double at, Geom::Point const &iS, PathDescrLineTo const &fin,
+ Geom::Point &pos, Geom::Point &tgt, double &len);
+ static void TangentOnArcAt(double at, Geom::Point const &iS, PathDescrArcTo const &fin,
+ Geom::Point &pos, Geom::Point &tgt, double &len, double &rad);
+ static void TangentOnCubAt (double at, Geom::Point const &iS, PathDescrCubicTo const &fin, bool before,
+ Geom::Point &pos, Geom::Point &tgt, double &len, double &rad);
+ static void TangentOnBezAt (double at, Geom::Point const &iS,
+ PathDescrIntermBezierTo & mid,
+ PathDescrBezierTo & fin, bool before,
+ Geom::Point & pos, Geom::Point & tgt, double &len, double &rad);
+ static void OutlineJoin (Path * dest, Geom::Point pos, Geom::Point stNor, Geom::Point enNor,
+ double width, JoinType join, double miter, int nType);
+
+ static bool IsNulCurve (std::vector<PathDescr*> const &cmd, int curD, Geom::Point const &curX);
+
+ static void RecStdCubicTo (outline_callback_data * data, double tol,
+ double width, int lev);
+ static void StdCubicTo (outline_callback_data * data, double tol,
+ double width);
+ static void StdBezierTo (outline_callback_data * data, double tol,
+ double width);
+ static void RecStdArcTo (outline_callback_data * data, double tol,
+ double width, int lev);
+ static void StdArcTo (outline_callback_data * data, double tol, double width);
+
+
+ // fonctions annexes pour le stroke
+ static void DoButt (Shape * dest, double width, ButtType butt, Geom::Point pos,
+ Geom::Point dir, int &leftNo, int &rightNo);
+ static void DoJoin (Shape * dest, double width, JoinType join, Geom::Point pos,
+ Geom::Point prev, Geom::Point next, double miter, double prevL,
+ double nextL, int *stNo, int *enNo);
+ static void DoLeftJoin (Shape * dest, double width, JoinType join, Geom::Point pos,
+ Geom::Point prev, Geom::Point next, double miter, double prevL,
+ double nextL, int &leftStNo, int &leftEnNo,int pathID=-1,int pieceID=0,double tID=0.0);
+ static void DoRightJoin (Shape * dest, double width, JoinType join, Geom::Point pos,
+ Geom::Point prev, Geom::Point next, double miter, double prevL,
+ double nextL, int &rightStNo, int &rightEnNo,int pathID=-1,int pieceID=0,double tID=0.0);
+ static void RecRound (Shape * dest, int sNo, int eNo,
+ Geom::Point const &iS, Geom::Point const &iE,
+ Geom::Point const &nS, Geom::Point const &nE,
+ Geom::Point &origine,float width);
+
+
+ void DoSimplify(int off, int N, double treshhold);
+ bool AttemptSimplify(int off, int N, double treshhold, PathDescrCubicTo &res, int &worstP);
+ static bool FitCubic(Geom::Point const &start,
+ PathDescrCubicTo &res,
+ double *Xk, double *Yk, double *Qk, double *tk, int nbPt);
+
+ struct fitting_tables {
+ int nbPt,maxPt,inPt;
+ double *Xk;
+ double *Yk;
+ double *Qk;
+ double *tk;
+ double *lk;
+ char *fk;
+ double totLen;
+ };
+ bool AttemptSimplify (fitting_tables &data,double treshhold, PathDescrCubicTo & res,int &worstP);
+ bool ExtendFit(int off, int N, fitting_tables &data,double treshhold, PathDescrCubicTo & res,int &worstP);
+ double RaffineTk (Geom::Point pt, Geom::Point p0, Geom::Point p1, Geom::Point p2, Geom::Point p3, double it);
+ void FlushPendingAddition(Path* dest,PathDescr *lastAddition,PathDescrCubicTo &lastCubic,int lastAD);
+
+private:
+ void AddCurve(Geom::Curve const &c);
+
+};
+#endif
+
+/*
+ Local Variables:
+ mode:c++
+ c-file-style:"stroustrup"
+ c-file-offsets:((innamespace . 0)(inline-open . 0)(case-label . +))
+ indent-tabs-mode:nil
+ fill-column:99
+ End:
+*/
+// vim: filetype=cpp:expandtab:shiftwidth=4:tabstop=8:softtabstop=4:fileencoding=utf-8:textwidth=99 :
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