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+// SPDX-License-Identifier: GPL-2.0-or-later
+/** @file
+ * Boolean operations.
+ *//*
+ * Authors:
+ * see git history
+ * Created by fred on Fri Dec 05 2003.
+ * tweaked endlessly by bulia byak <buliabyak@users.sf.net>
+ *
+ * Copyright (C) 2018 Authors
+ * Released under GNU GPL v2+, read the file 'COPYING' for more information.
+ */
+
+#include <vector>
+
+#include <glibmm/i18n.h>
+#include <2geom/intersection-graph.h>
+#include <2geom/svg-path-parser.h> // to get from SVG on boolean to Geom::Path
+#include <2geom/utils.h>
+
+#include "path-boolop.h"
+#include "path-util.h"
+
+#include "message-stack.h"
+#include "path-chemistry.h" // copy_object_properties()
+
+#include "helper/geom.h" // pathv_to_linear_and_cubic_beziers()
+
+#include "livarot/Path.h"
+#include "livarot/Shape.h"
+
+#include "object/sp-flowtext.h"
+#include "object/sp-shape.h"
+#include "object/sp-text.h"
+
+#include "display/curve.h"
+
+#include "ui/icon-names.h"
+#include "ui/widget/canvas.h" // Disable drawing during op
+
+#include "svg/svg.h"
+
+#include "xml/repr-sorting.h"
+
+using Inkscape::DocumentUndo;
+
+// fonctions utilitaires
+bool
+Ancetre(Inkscape::XML::Node *a, Inkscape::XML::Node *who)
+{
+ if (who == nullptr || a == nullptr)
+ return false;
+ if (who == a)
+ return true;
+ return Ancetre(a->parent(), who);
+}
+
+
+bool Inkscape::ObjectSet::pathUnion(const bool skip_undo, bool silent) {
+ BoolOpErrors result = pathBoolOp(bool_op_union, skip_undo, false, INKSCAPE_ICON("path-union"),
+ _("Union"), silent);
+ return DONE == result;
+}
+
+bool
+Inkscape::ObjectSet::pathIntersect(const bool skip_undo, bool silent)
+{
+ BoolOpErrors result = pathBoolOp(bool_op_inters, skip_undo, false, INKSCAPE_ICON("path-intersection"),
+ _("Intersection"), silent);
+ return DONE == result;
+}
+
+bool
+Inkscape::ObjectSet::pathDiff(const bool skip_undo, bool silent)
+{
+ BoolOpErrors result = pathBoolOp(bool_op_diff, skip_undo, false, INKSCAPE_ICON("path-difference"),
+ _("Difference"), silent);
+ return DONE == result;
+}
+
+bool
+Inkscape::ObjectSet::pathSymDiff(const bool skip_undo, bool silent)
+{
+ BoolOpErrors result = pathBoolOp(bool_op_symdiff, skip_undo, false, INKSCAPE_ICON("path-exclusion"),
+ _("Exclusion"), silent);
+ return DONE == result;
+}
+
+bool
+Inkscape::ObjectSet::pathCut(const bool skip_undo, bool silent)
+{
+ BoolOpErrors result = pathBoolOp(bool_op_cut, skip_undo, false, INKSCAPE_ICON("path-division"),
+ _("Division"), silent);
+ return DONE == result;
+}
+
+bool
+Inkscape::ObjectSet::pathSlice(const bool skip_undo, bool silent)
+{
+ BoolOpErrors result = pathBoolOp(bool_op_slice, skip_undo, false, INKSCAPE_ICON("path-cut"),
+ _("Cut path"), silent);
+ return DONE == result;
+}
+
+// helper for printing error messages, regardless of whether we have a GUI or not
+// If desktop == NULL, errors will be shown on stderr
+static void
+boolop_display_error_message(SPDesktop *desktop, Glib::ustring const &msg)
+{
+ if (desktop) {
+ desktop->messageStack()->flash(Inkscape::ERROR_MESSAGE, msg);
+ } else {
+ g_printerr("%s\n", msg.c_str());
+ }
+}
+
+/**
+ * Calculate the threshold for the given PathVector based
+ * on it's bounding box.
+ *
+ * @param path - The PathVector to calculate the threshold for.
+ * @param threshold - The starting threshold, usually 0.1
+ */
+double get_threshold(Geom::PathVector const &path, double threshold)
+{
+ auto maybe_box = path.boundsFast();
+ if (!maybe_box)
+ return threshold;
+ Geom::Rect box = *maybe_box;
+ double diagonal = Geom::distance(
+ Geom::Point(box[Geom::X].min(), box[Geom::Y].min()),
+ Geom::Point(box[Geom::X].max(), box[Geom::Y].max())
+ );
+ return threshold * (diagonal / 100);
+}
+
+/**
+ * Calculate the threshold for the given SPItem/SPShape based
+ * on it's bounding box (see PathVector get_threshold above)
+ *
+ * @param item - The SPItem to calculate the threshold for.
+ * @param threshold - The starting threshold, usually 0.1
+ */
+double get_threshold(SPItem const *item, double threshold)
+{
+ auto shape = dynamic_cast<SPShape const *>(item);
+ if (shape && shape->curve()) {
+ return get_threshold(shape->curve()->get_pathvector(), threshold);
+ }
+ return threshold;
+}
+
+void
+sp_flatten(Geom::PathVector &pathvector, FillRule fillkind)
+{
+ Path *orig = new Path;
+ orig->LoadPathVector(pathvector);
+ Shape *theShape = new Shape;
+ Shape *theRes = new Shape;
+ orig->ConvertWithBackData(1.0);
+ orig->Fill(theShape, 0);
+ theRes->ConvertToShape(theShape, fillkind);
+ Path *originaux[1];
+ originaux[0] = orig;
+ Path *res = new Path;
+ theRes->ConvertToForme(res, 1, originaux, true);
+
+ delete theShape;
+ delete theRes;
+ char *res_d = res->svg_dump_path();
+ delete res;
+ delete orig;
+ pathvector = sp_svg_read_pathv(res_d);
+}
+
+// boolean operations PathVectors A,B -> PathVector result.
+// This is derived from sp_selected_path_boolop
+// take the source paths from the file, do the operation, delete the originals and add the results
+// fra,fra are fill_rules for PathVectors a,b
+Geom::PathVector
+sp_pathvector_boolop(Geom::PathVector const &pathva, Geom::PathVector const &pathvb, bool_op bop,
+ fill_typ fra, fill_typ frb, bool livarotonly, bool flattenbefore)
+{
+ int error = 0;
+ return sp_pathvector_boolop(pathva, pathvb, bop, fra, frb, livarotonly, flattenbefore, error);
+}
+
+Geom::PathVector
+sp_pathvector_boolop(Geom::PathVector const &pathva, Geom::PathVector const &pathvb, bool_op bop,
+ fill_typ fra, fill_typ frb, bool livarotonly, bool flattenbefore, int &error)
+{
+ if (!livarotonly) {
+ try {
+ Geom::PathVector a = pathv_to_linear_and_cubic_beziers(pathva);
+ Geom::PathVector b = pathv_to_linear_and_cubic_beziers(pathvb);
+ if (flattenbefore) {
+ sp_flatten(a, fra);
+ sp_flatten(b, frb);
+ }
+ Geom::PathVector out;
+ // dont change tolerande give errors on boolops
+ auto pig = Geom::PathIntersectionGraph(a, b, Geom::EPSILON);
+ if (bop == bool_op_inters) {
+ out = pig.getIntersection();
+ } else if (bop == bool_op_union) {
+ out = pig.getUnion();
+
+ } else if (bop == bool_op_symdiff) {
+ out = pig.getXOR();
+ } else if (bop == bool_op_diff) {
+ out = pig.getBminusA(); //livarot order...
+ } else if (bop == bool_op_cut) {
+ out = pig.getBminusA();
+ auto tmp = pig.getIntersection();
+ out.insert(out.end(), tmp.begin(), tmp.end());
+ } else if (bop == bool_op_slice) {
+ // go to livarot
+ livarotonly = true;
+ }
+ if (!livarotonly) {
+ return out;
+ }
+ } catch (...) {
+ g_debug("Path Intersection Graph failed boolops, fallback to livarot");
+ }
+ }
+ error = 1;
+ // extract the livarot Paths from the source objects
+ // also get the winding rule specified in the style
+ int nbOriginaux = 2;
+ std::vector<Path *> originaux(nbOriginaux);
+ std::vector<FillRule> origWind(nbOriginaux);
+ origWind[0]=fra;
+ origWind[1]=frb;
+ Geom::PathVector patht;
+ // Livarot's outline of arcs is broken. So convert the path to linear and cubics only, for which the outline is created correctly.
+ originaux[0] = Path_for_pathvector(pathv_to_linear_and_cubic_beziers( pathva));
+ originaux[1] = Path_for_pathvector(pathv_to_linear_and_cubic_beziers( pathvb));
+
+ // some temporary instances, first
+ Shape *theShapeA = new Shape;
+ Shape *theShapeB = new Shape;
+ Shape *theShape = new Shape;
+ Path *res = new Path;
+ res->SetBackData(false);
+
+ Path::cut_position *toCut=nullptr;
+ int nbToCut = 0;
+
+ if ( bop == bool_op_inters || bop == bool_op_union || bop == bool_op_diff || bop == bool_op_symdiff ) {
+ // true boolean op
+ // get the polygons of each path, with the winding rule specified, and apply the operation iteratively
+ originaux[0]->ConvertWithBackData(get_threshold(pathva, 0.1));
+
+ originaux[0]->Fill(theShape, 0);
+
+ theShapeA->ConvertToShape(theShape, origWind[0]);
+
+ originaux[1]->ConvertWithBackData(get_threshold(pathvb, 0.1));
+
+ originaux[1]->Fill(theShape, 1);
+
+ theShapeB->ConvertToShape(theShape, origWind[1]);
+
+ theShape->Booleen(theShapeB, theShapeA, bop);
+
+ } else if ( bop == bool_op_cut ) {
+ // cuts= sort of a bastard boolean operation, thus not the axact same modus operandi
+ // technically, the cut path is not necessarily a polygon (thus has no winding rule)
+ // it is just uncrossed, and cleaned from duplicate edges and points
+ // then it's fed to Booleen() which will uncross it against the other path
+ // then comes the trick: each edge of the cut path is duplicated (one in each direction),
+ // thus making a polygon. the weight of the edges of the cut are all 0, but
+ // the Booleen need to invert the ones inside the source polygon (for the subsequent
+ // ConvertToForme)
+
+ // the cut path needs to have the highest pathID in the back data
+ // that's how the Booleen() function knows it's an edge of the cut
+ {
+ Path* swap=originaux[0];originaux[0]=originaux[1];originaux[1]=swap;
+ int swai=origWind[0];origWind[0]=origWind[1];origWind[1]=(fill_typ)swai;
+ }
+ originaux[0]->ConvertWithBackData(get_threshold(pathva, 0.1));
+
+ originaux[0]->Fill(theShape, 0);
+
+ theShapeA->ConvertToShape(theShape, origWind[0]);
+
+ originaux[1]->ConvertWithBackData(get_threshold(pathvb, 0.1));
+
+ originaux[1]->Fill(theShape, 1,false,false,false); //do not closeIfNeeded
+
+ theShapeB->ConvertToShape(theShape, fill_justDont); // fill_justDont doesn't computes winding numbers
+
+ // les elements arrivent en ordre inverse dans la liste
+ theShape->Booleen(theShapeB, theShapeA, bool_op_cut, 1);
+
+ } else if ( bop == bool_op_slice ) {
+ // slice is not really a boolean operation
+ // you just put the 2 shapes in a single polygon, uncross it
+ // the points where the degree is > 2 are intersections
+ // just check it's an intersection on the path you want to cut, and keep it
+ // the intersections you have found are then fed to ConvertPositionsToMoveTo() which will
+ // make new subpath at each one of these positions
+ // inversion pour l'opération
+ {
+ Path* swap=originaux[0];originaux[0]=originaux[1];originaux[1]=swap;
+ int swai=origWind[0];origWind[0]=origWind[1];origWind[1]=(fill_typ)swai;
+ }
+ originaux[0]->ConvertWithBackData(get_threshold(pathva, 0.1));
+
+ originaux[0]->Fill(theShapeA, 0,false,false,false); // don't closeIfNeeded
+
+ originaux[1]->ConvertWithBackData(get_threshold(pathvb, 0.1));
+
+ originaux[1]->Fill(theShapeA, 1,true,false,false);// don't closeIfNeeded and just dump in the shape, don't reset it
+
+ theShape->ConvertToShape(theShapeA, fill_justDont);
+
+ if ( theShape->hasBackData() ) {
+ // should always be the case, but ya never know
+ {
+ for (int i = 0; i < theShape->numberOfPoints(); i++) {
+ if ( theShape->getPoint(i).totalDegree() > 2 ) {
+ // possibly an intersection
+ // we need to check that at least one edge from the source path is incident to it
+ // before we declare it's an intersection
+ int cb = theShape->getPoint(i).incidentEdge[FIRST];
+ int nbOrig=0;
+ int nbOther=0;
+ int piece=-1;
+ float t=0.0;
+ while ( cb >= 0 && cb < theShape->numberOfEdges() ) {
+ if ( theShape->ebData[cb].pathID == 0 ) {
+ // the source has an edge incident to the point, get its position on the path
+ piece=theShape->ebData[cb].pieceID;
+ if ( theShape->getEdge(cb).st == i ) {
+ t=theShape->ebData[cb].tSt;
+ } else {
+ t=theShape->ebData[cb].tEn;
+ }
+ nbOrig++;
+ }
+ if ( theShape->ebData[cb].pathID == 1 ) nbOther++; // the cut is incident to this point
+ cb=theShape->NextAt(i, cb);
+ }
+ if ( nbOrig > 0 && nbOther > 0 ) {
+ // point incident to both path and cut: an intersection
+ // note that you only keep one position on the source; you could have degenerate
+ // cases where the source crosses itself at this point, and you wouyld miss an intersection
+ toCut=(Path::cut_position*)realloc(toCut, (nbToCut+1)*sizeof(Path::cut_position));
+ toCut[nbToCut].piece=piece;
+ toCut[nbToCut].t=t;
+ nbToCut++;
+ }
+ }
+ }
+ }
+ {
+ // i think it's useless now
+ int i = theShape->numberOfEdges() - 1;
+ for (;i>=0;i--) {
+ if ( theShape->ebData[i].pathID == 1 ) {
+ theShape->SubEdge(i);
+ }
+ }
+ }
+
+ }
+ }
+
+ int* nesting=nullptr;
+ int* conts=nullptr;
+ int nbNest=0;
+ // pour compenser le swap juste avant
+ if ( bop == bool_op_slice ) {
+// theShape->ConvertToForme(res, nbOriginaux, originaux, true);
+// res->ConvertForcedToMoveTo();
+ res->Copy(originaux[0]);
+ res->ConvertPositionsToMoveTo(nbToCut, toCut); // cut where you found intersections
+ free(toCut);
+ } else if ( bop == bool_op_cut ) {
+ // il faut appeler pour desallouer PointData (pas vital, mais bon)
+ // the Booleen() function did not deallocate the point_data array in theShape, because this
+ // function needs it.
+ // this function uses the point_data to get the winding number of each path (ie: is a hole or not)
+ // for later reconstruction in objects, you also need to extract which path is parent of holes (nesting info)
+ theShape->ConvertToFormeNested(res, nbOriginaux, &originaux[0], 1, nbNest, nesting, conts);
+ } else {
+ theShape->ConvertToForme(res, nbOriginaux, &originaux[0]);
+ }
+
+ delete theShape;
+ delete theShapeA;
+ delete theShapeB;
+ delete originaux[0];
+ delete originaux[1];
+
+ gchar *result_str = res->svg_dump_path();
+ Geom::PathVector outres = Geom::parse_svg_path(result_str);
+ g_free(result_str);
+
+ delete res;
+ return outres;
+}
+
+/**
+ * Workaround for buggy Path::Transform() which incorrectly transforms arc commands.
+ *
+ * TODO: Fix PathDescrArcTo::transform() and then remove this workaround.
+ */
+static void transformLivarotPath(Path *res, Geom::Affine const &affine)
+{
+ res->LoadPathVector(res->MakePathVector() * affine);
+}
+
+// boolean operations on the desktop
+// take the source paths from the file, do the operation, delete the originals and add the results
+BoolOpErrors Inkscape::ObjectSet::pathBoolOp(bool_op bop, const bool skip_undo, const bool checked,
+ const Glib::ustring icon_name, const Glib::ustring description,
+ bool const silent)
+{
+ if (nullptr != desktop() && !checked) {
+ SPDocument *doc = desktop()->getDocument();
+ // don't redraw the canvas during the operation as that can remarkably slow down the progress
+ desktop()->getCanvas()->set_drawing_disabled(true);
+ BoolOpErrors returnCode = ObjectSet::pathBoolOp(bop, true, true,icon_name);
+ desktop()->getCanvas()->set_drawing_disabled(false);
+
+ switch(returnCode) {
+ case ERR_TOO_LESS_PATHS_1:
+ if (!silent) {
+ boolop_display_error_message(desktop(),
+ _("Select <b>at least 1 path</b> to perform a boolean union."));
+ }
+ break;
+ case ERR_TOO_LESS_PATHS_2:
+ if (!silent) {
+ boolop_display_error_message(desktop(),
+ _("Select <b>at least 2 paths</b> to perform a boolean operation."));
+ }
+ break;
+ case ERR_NO_PATHS:
+ if (!silent) {
+ boolop_display_error_message(desktop(),
+ _("One of the objects is <b>not a path</b>, cannot perform boolean operation."));
+ }
+ break;
+ case ERR_Z_ORDER:
+ if (!silent) {
+ boolop_display_error_message(desktop(),
+ _("Unable to determine the <b>z-order</b> of the objects selected for difference, XOR, division, or path cut."));
+ }
+ break;
+ case DONE_NO_PATH:
+ if (!skip_undo) {
+ DocumentUndo::done(doc, description, "");
+ }
+ break;
+ case DONE:
+ if (!skip_undo) {
+ DocumentUndo::done(doc, description, icon_name);
+ }
+ break;
+ case DONE_NO_ACTION:
+ // Do nothing (?)
+ break;
+ }
+ return returnCode;
+ }
+
+ SPDocument *doc = document();
+ std::vector<SPItem*> il(items().begin(), items().end());
+
+ // allow union on a single object for the purpose of removing self overlapse (svn log, revision 13334)
+ if (il.size() < 2 && bop != bool_op_union) {
+ return ERR_TOO_LESS_PATHS_2;
+ }
+ else if (il.size() < 1) {
+ return ERR_TOO_LESS_PATHS_1;
+ }
+
+ g_assert(!il.empty());
+
+ // reverseOrderForOp marks whether the order of the list is the top->down order
+ // it's only used when there are 2 objects, and for operations who need to know the
+ // topmost object (differences, cuts)
+ bool reverseOrderForOp = false;
+
+ if (bop == bool_op_diff || bop == bool_op_cut || bop == bool_op_slice) {
+ // check in the tree to find which element of the selection list is topmost (for 2-operand commands only)
+ Inkscape::XML::Node *a = il.front()->getRepr();
+ Inkscape::XML::Node *b = il.back()->getRepr();
+
+ if (a == nullptr || b == nullptr) {
+ return ERR_Z_ORDER;
+ }
+
+ if (Ancetre(a, b)) {
+ // a is the parent of b, already in the proper order
+ } else if (Ancetre(b, a)) {
+ // reverse order
+ reverseOrderForOp = true;
+ } else {
+
+ // objects are not in parent/child relationship;
+ // find their lowest common ancestor
+ Inkscape::XML::Node *parent = LCA(a, b);
+ if (parent == nullptr) {
+ return ERR_Z_ORDER;
+ }
+
+ // find the children of the LCA that lead from it to the a and b
+ Inkscape::XML::Node *as = AncetreFils(a, parent);
+ Inkscape::XML::Node *bs = AncetreFils(b, parent);
+
+ // find out which comes first
+ for (Inkscape::XML::Node *child = parent->firstChild(); child; child = child->next()) {
+ if (child == as) {
+ /* a first, so reverse. */
+ reverseOrderForOp = true;
+ break;
+ }
+ if (child == bs)
+ break;
+ }
+ }
+ }
+
+ g_assert(!il.empty());
+
+ // first check if all the input objects have shapes
+ // otherwise bail out
+ for (auto item : il)
+ {
+ if (!SP_IS_SHAPE(item) && !SP_IS_TEXT(item) && !SP_IS_FLOWTEXT(item))
+ {
+ return ERR_NO_PATHS;
+ }
+ }
+
+ // extract the livarot Paths from the source objects
+ // also get the winding rule specified in the style
+ int nbOriginaux = il.size();
+ std::vector<Path *> originaux(nbOriginaux);
+ std::vector<FillRule> origWind(nbOriginaux);
+ int curOrig;
+ {
+ curOrig = 0;
+ for (auto item : il)
+ {
+ // apply live path effects prior to performing boolean operation
+ char const *id = item->getAttribute("id");
+ SPLPEItem *lpeitem = dynamic_cast<SPLPEItem *>(item);
+ if (lpeitem) {
+ SPDocument * document = item->document;
+ lpeitem->removeAllPathEffects(true);
+ SPObject *elemref = document->getObjectById(id);
+ if (elemref && elemref != item) {
+ // If the LPE item is a shape, it is converted to a path
+ // so we need to reupdate the item
+ item = dynamic_cast<SPItem *>(elemref);
+ }
+ }
+ SPCSSAttr *css = sp_repr_css_attr(reinterpret_cast<SPObject *>(il[0])->getRepr(), "style");
+ gchar const *val = sp_repr_css_property(css, "fill-rule", nullptr);
+ if (val && strcmp(val, "nonzero") == 0) {
+ origWind[curOrig]= fill_nonZero;
+ } else if (val && strcmp(val, "evenodd") == 0) {
+ origWind[curOrig]= fill_oddEven;
+ } else {
+ origWind[curOrig]= fill_nonZero;
+ }
+
+ originaux[curOrig] = Path_for_item(item, true, true);
+ if (originaux[curOrig] == nullptr || originaux[curOrig]->descr_cmd.size() <= 1)
+ {
+ for (int i = curOrig; i >= 0; i--) delete originaux[i];
+ return DONE_NO_ACTION;
+ }
+ curOrig++;
+ }
+ }
+ // reverse if needed
+ // note that the selection list keeps its order
+ if ( reverseOrderForOp ) {
+ std::swap(originaux[0], originaux[1]);
+ std::swap(origWind[0], origWind[1]);
+ }
+
+ // and work
+ // some temporary instances, first
+ Shape *theShapeA = new Shape;
+ Shape *theShapeB = new Shape;
+ Shape *theShape = new Shape;
+ Path *res = new Path;
+ res->SetBackData(false);
+ Path::cut_position *toCut=nullptr;
+ int nbToCut=0;
+
+ if ( bop == bool_op_inters || bop == bool_op_union || bop == bool_op_diff || bop == bool_op_symdiff ) {
+ // true boolean op
+ // get the polygons of each path, with the winding rule specified, and apply the operation iteratively
+ originaux[0]->ConvertWithBackData(get_threshold(il[0], 0.1));
+
+ originaux[0]->Fill(theShape, 0);
+
+ theShapeA->ConvertToShape(theShape, origWind[0]);
+
+ curOrig = 1;
+ for (auto item : il){
+ if(item==il[0])continue;
+ originaux[curOrig]->ConvertWithBackData(get_threshold(item, 0.1));
+
+ originaux[curOrig]->Fill(theShape, curOrig);
+
+ theShapeB->ConvertToShape(theShape, origWind[curOrig]);
+
+ /* Due to quantization of the input shape coordinates, we may end up with A or B being empty.
+ * If this is a union or symdiff operation, we just use the non-empty shape as the result:
+ * A=0 => (0 or B) == B
+ * B=0 => (A or 0) == A
+ * A=0 => (0 xor B) == B
+ * B=0 => (A xor 0) == A
+ * If this is an intersection operation, we just use the empty shape as the result:
+ * A=0 => (0 and B) == 0 == A
+ * B=0 => (A and 0) == 0 == B
+ * If this a difference operation, and the upper shape (A) is empty, we keep B.
+ * If the lower shape (B) is empty, we still keep B, as it's empty:
+ * A=0 => (B - 0) == B
+ * B=0 => (0 - A) == 0 == B
+ *
+ * In any case, the output from this operation is stored in shape A, so we may apply
+ * the above rules simply by judicious use of swapping A and B where necessary.
+ */
+ bool zeroA = theShapeA->numberOfEdges() == 0;
+ bool zeroB = theShapeB->numberOfEdges() == 0;
+ if (zeroA || zeroB) {
+ // We might need to do a swap. Apply the above rules depending on operation type.
+ bool resultIsB = ((bop == bool_op_union || bop == bool_op_symdiff) && zeroA)
+ || ((bop == bool_op_inters) && zeroB)
+ || (bop == bool_op_diff);
+ if (resultIsB) {
+ // Swap A and B to use B as the result
+ Shape *swap = theShapeB;
+ theShapeB = theShapeA;
+ theShapeA = swap;
+ }
+ } else {
+ // Just do the Boolean operation as usual
+ // les elements arrivent en ordre inverse dans la liste
+ theShape->Booleen(theShapeB, theShapeA, bop);
+ Shape *swap = theShape;
+ theShape = theShapeA;
+ theShapeA = swap;
+ }
+ curOrig++;
+ }
+
+ {
+ Shape *swap = theShape;
+ theShape = theShapeA;
+ theShapeA = swap;
+ }
+
+ } else if ( bop == bool_op_cut ) {
+ // cuts= sort of a bastard boolean operation, thus not the axact same modus operandi
+ // technically, the cut path is not necessarily a polygon (thus has no winding rule)
+ // it is just uncrossed, and cleaned from duplicate edges and points
+ // then it's fed to Booleen() which will uncross it against the other path
+ // then comes the trick: each edge of the cut path is duplicated (one in each direction),
+ // thus making a polygon. the weight of the edges of the cut are all 0, but
+ // the Booleen need to invert the ones inside the source polygon (for the subsequent
+ // ConvertToForme)
+
+ // the cut path needs to have the highest pathID in the back data
+ // that's how the Booleen() function knows it's an edge of the cut
+ {
+ Path* swap=originaux[0];originaux[0]=originaux[1];originaux[1]=swap;
+ int swai=origWind[0];origWind[0]=origWind[1];origWind[1]=(fill_typ)swai;
+ }
+ originaux[0]->ConvertWithBackData(get_threshold(il[0], 0.1));
+
+ originaux[0]->Fill(theShape, 0);
+
+ theShapeA->ConvertToShape(theShape, origWind[0]);
+
+ originaux[1]->ConvertWithBackData(get_threshold(il[1], 0.1));
+
+ if ((originaux[1]->pts.size() == 2) && originaux[1]->pts[0].isMoveTo && !originaux[1]->pts[1].isMoveTo)
+ originaux[1]->Fill(theShape, 1,false,true,false); // see LP Bug 177956
+ else
+ originaux[1]->Fill(theShape, 1,false,false,false); //do not closeIfNeeded
+
+ theShapeB->ConvertToShape(theShape, fill_justDont); // fill_justDont doesn't computes winding numbers
+
+ // les elements arrivent en ordre inverse dans la liste
+ theShape->Booleen(theShapeB, theShapeA, bool_op_cut, 1);
+
+ } else if ( bop == bool_op_slice ) {
+ // slice is not really a boolean operation
+ // you just put the 2 shapes in a single polygon, uncross it
+ // the points where the degree is > 2 are intersections
+ // just check it's an intersection on the path you want to cut, and keep it
+ // the intersections you have found are then fed to ConvertPositionsToMoveTo() which will
+ // make new subpath at each one of these positions
+ // inversion pour l'opération
+ {
+ Path* swap=originaux[0];originaux[0]=originaux[1];originaux[1]=swap;
+ int swai=origWind[0];origWind[0]=origWind[1];origWind[1]=(fill_typ)swai;
+ }
+ originaux[0]->ConvertWithBackData(get_threshold(il[0], 0.1));
+
+ originaux[0]->Fill(theShapeA, 0,false,false,false); // don't closeIfNeeded
+
+ originaux[1]->ConvertWithBackData(get_threshold(il[1], 0.1));
+
+ originaux[1]->Fill(theShapeA, 1,true,false,false);// don't closeIfNeeded and just dump in the shape, don't reset it
+
+ theShape->ConvertToShape(theShapeA, fill_justDont);
+
+ if ( theShape->hasBackData() ) {
+ // should always be the case, but ya never know
+ {
+ for (int i = 0; i < theShape->numberOfPoints(); i++) {
+ if ( theShape->getPoint(i).totalDegree() > 2 ) {
+ // possibly an intersection
+ // we need to check that at least one edge from the source path is incident to it
+ // before we declare it's an intersection
+ int cb = theShape->getPoint(i).incidentEdge[FIRST];
+ int nbOrig=0;
+ int nbOther=0;
+ int piece=-1;
+ float t=0.0;
+ while ( cb >= 0 && cb < theShape->numberOfEdges() ) {
+ if ( theShape->ebData[cb].pathID == 0 ) {
+ // the source has an edge incident to the point, get its position on the path
+ piece=theShape->ebData[cb].pieceID;
+ if ( theShape->getEdge(cb).st == i ) {
+ t=theShape->ebData[cb].tSt;
+ } else {
+ t=theShape->ebData[cb].tEn;
+ }
+ nbOrig++;
+ }
+ if ( theShape->ebData[cb].pathID == 1 ) nbOther++; // the cut is incident to this point
+ cb=theShape->NextAt(i, cb);
+ }
+ if ( nbOrig > 0 && nbOther > 0 ) {
+ // point incident to both path and cut: an intersection
+ // note that you only keep one position on the source; you could have degenerate
+ // cases where the source crosses itself at this point, and you wouyld miss an intersection
+ toCut=(Path::cut_position*)realloc(toCut, (nbToCut+1)*sizeof(Path::cut_position));
+ toCut[nbToCut].piece=piece;
+ toCut[nbToCut].t=t;
+ nbToCut++;
+ }
+ }
+ }
+ }
+ {
+ // i think it's useless now
+ int i = theShape->numberOfEdges() - 1;
+ for (;i>=0;i--) {
+ if ( theShape->ebData[i].pathID == 1 ) {
+ theShape->SubEdge(i);
+ }
+ }
+ }
+
+ }
+ }
+
+ int* nesting=nullptr;
+ int* conts=nullptr;
+ int nbNest=0;
+ // pour compenser le swap juste avant
+ if ( bop == bool_op_slice ) {
+// theShape->ConvertToForme(res, nbOriginaux, originaux, true);
+// res->ConvertForcedToMoveTo();
+ res->Copy(originaux[0]);
+ res->ConvertPositionsToMoveTo(nbToCut, toCut); // cut where you found intersections
+ free(toCut);
+ } else if ( bop == bool_op_cut ) {
+ // il faut appeler pour desallouer PointData (pas vital, mais bon)
+ // the Booleen() function did not deallocate the point_data array in theShape, because this
+ // function needs it.
+ // this function uses the point_data to get the winding number of each path (ie: is a hole or not)
+ // for later reconstruction in objects, you also need to extract which path is parent of holes (nesting info)
+ theShape->ConvertToFormeNested(res, nbOriginaux, &originaux[0], 1, nbNest, nesting, conts);
+ } else {
+ theShape->ConvertToForme(res, nbOriginaux, &originaux[0]);
+ }
+
+ delete theShape;
+ delete theShapeA;
+ delete theShapeB;
+ for (int i = 0; i < nbOriginaux; i++) delete originaux[i];
+
+ if (res->descr_cmd.size() <= 1)
+ {
+ // only one command, presumably a moveto: it isn't a path
+ for (auto l : il){
+ l->deleteObject();
+ }
+ clear();
+
+ delete res;
+ return DONE_NO_PATH;
+ }
+
+ // get the source path object
+ SPObject *source;
+ if ( bop == bool_op_diff || bop == bool_op_cut || bop == bool_op_slice ) {
+ if (reverseOrderForOp) {
+ source = il[0];
+ } else {
+ source = il.back();
+ }
+ } else {
+ // find out the bottom object
+ std::vector<Inkscape::XML::Node*> sorted(xmlNodes().begin(), xmlNodes().end());
+
+ sort(sorted.begin(),sorted.end(),sp_repr_compare_position_bool);
+
+ source = doc->getObjectByRepr(sorted.front());
+ }
+
+ // adjust style properties that depend on a possible transform in the source object in order
+ // to get a correct style attribute for the new path
+ SPItem* item_source = SP_ITEM(source);
+ Geom::Affine i2doc(item_source->i2doc_affine());
+
+ Inkscape::XML::Node *repr_source = source->getRepr();
+
+ // remember important aspects of the source path, to be restored
+ gint pos = repr_source->position();
+ Inkscape::XML::Node *parent = repr_source->parent();
+ // remove source paths
+ clear();
+ for (auto l : il){
+ if (l != item_source) {
+ // delete the object for real, so that its clones can take appropriate action
+ l->deleteObject();
+ }
+ }
+
+ auto const source2doc_inverse = i2doc.inverse();
+ char const *const old_transform_attibute = repr_source->attribute("transform");
+
+ // now that we have the result, add it on the canvas
+ if ( bop == bool_op_cut || bop == bool_op_slice ) {
+ int nbRP=0;
+ Path** resPath;
+ if ( bop == bool_op_slice ) {
+ // there are moveto's at each intersection, but it's still one unique path
+ // so break it down and add each subpath independently
+ // we could call break_apart to do this, but while we have the description...
+ resPath=res->SubPaths(nbRP, false);
+ } else {
+ // cut operation is a bit wicked: you need to keep holes
+ // that's why you needed the nesting
+ // ConvertToFormeNested() dumped all the subpath in a single Path "res", so we need
+ // to get the path for each part of the polygon. that's why you need the nesting info:
+ // to know in which subpath to add a subpath
+ resPath=res->SubPathsWithNesting(nbRP, true, nbNest, nesting, conts);
+
+ // cleaning
+ if ( conts ) free(conts);
+ if ( nesting ) free(nesting);
+ }
+
+ // add all the pieces resulting from cut or slice
+ std::vector <Inkscape::XML::Node*> selection;
+ for (int i=0;i<nbRP;i++) {
+ transformLivarotPath(resPath[i], source2doc_inverse);
+ gchar *d = resPath[i]->svg_dump_path();
+
+ Inkscape::XML::Document *xml_doc = doc->getReprDoc();
+ Inkscape::XML::Node *repr = xml_doc->createElement("svg:path");
+
+ Inkscape::copy_object_properties(repr, repr_source);
+
+ // Delete source on last iteration (after we don't need repr_source anymore). As a consequence, the last
+ // item will inherit the original's id.
+ if (i + 1 == nbRP) {
+ item_source->deleteObject(false);
+ }
+
+ repr->setAttribute("d", d);
+ g_free(d);
+
+ // for slice, remove fill
+ if (bop == bool_op_slice) {
+ SPCSSAttr *css;
+
+ css = sp_repr_css_attr_new();
+ sp_repr_css_set_property(css, "fill", "none");
+
+ sp_repr_css_change(repr, css, "style");
+
+ sp_repr_css_attr_unref(css);
+ }
+
+ repr->setAttributeOrRemoveIfEmpty("transform", old_transform_attibute);
+
+ // add the new repr to the parent
+ // move to the saved position
+ parent->addChildAtPos(repr, pos);
+
+ selection.push_back(repr);
+ Inkscape::GC::release(repr);
+
+ delete resPath[i];
+ }
+ setReprList(selection);
+ if ( resPath ) free(resPath);
+
+ } else {
+ transformLivarotPath(res, source2doc_inverse);
+ gchar *d = res->svg_dump_path();
+
+ Inkscape::XML::Document *xml_doc = doc->getReprDoc();
+ Inkscape::XML::Node *repr = xml_doc->createElement("svg:path");
+
+ Inkscape::copy_object_properties(repr, repr_source);
+
+ // delete it so that its clones don't get alerted; this object will be restored shortly, with the same id
+ item_source->deleteObject(false);
+
+ repr->setAttribute("d", d);
+ g_free(d);
+
+ repr->setAttributeOrRemoveIfEmpty("transform", old_transform_attibute);
+
+ parent->addChildAtPos(repr, pos);
+
+ set(repr);
+ Inkscape::GC::release(repr);
+ }
+
+ delete res;
+
+ return DONE;
+}
+
+/*
+ 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 :