// 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 #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 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 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 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 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 :