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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:24:48 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:24:48 +0000 |
commit | cca66b9ec4e494c1d919bff0f71a820d8afab1fa (patch) | |
tree | 146f39ded1c938019e1ed42d30923c2ac9e86789 /src/livarot/Path.h | |
parent | Initial commit. (diff) | |
download | inkscape-upstream.tar.xz inkscape-upstream.zip |
Adding upstream version 1.2.2.upstream/1.2.2upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'src/livarot/Path.h')
-rw-r--r-- | src/livarot/Path.h | 416 |
1 files changed, 416 insertions, 0 deletions
diff --git a/src/livarot/Path.h b/src/livarot/Path.h new file mode 100644 index 0000000..163d955 --- /dev/null +++ b/src/livarot/Path.h @@ -0,0 +1,416 @@ +// 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 : |