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Diffstat (limited to 'src/live_effects/lpe-dashed-stroke.cpp')
| -rw-r--r-- | src/live_effects/lpe-dashed-stroke.cpp | 282 |
1 files changed, 282 insertions, 0 deletions
diff --git a/src/live_effects/lpe-dashed-stroke.cpp b/src/live_effects/lpe-dashed-stroke.cpp new file mode 100644 index 0000000..7edbeac --- /dev/null +++ b/src/live_effects/lpe-dashed-stroke.cpp @@ -0,0 +1,282 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Released under GNU GPL v2+, read the file 'COPYING' for more information. + */ +#include "live_effects/lpe-dashed-stroke.h" +#include "2geom/path.h" +#include "2geom/pathvector.h" +#include "helper/geom.h" + +// TODO due to internal breakage in glibmm headers, this must be last: +#include <glibmm/i18n.h> + +namespace Inkscape { +namespace LivePathEffect { + +LPEDashedStroke::LPEDashedStroke(LivePathEffectObject *lpeobject) + : Effect(lpeobject) + , numberdashes(_("Number of dashes"), _("Number of dashes"), "numberdashes", &wr, this, 3) + , holefactor(_("Hole factor"), _("Hole factor"), "holefactor", &wr, this, 0.0) + , splitsegments(_("Use segments"), _("Use segments"), "splitsegments", &wr, this, true) + , halfextreme(_("Half start/end"), _("Start and end of each segment has half size"), "halfextreme", &wr, this, true) + , unifysegment(_("Equalize dashes"), _("Global dash length is approximately the length of the dashes in the shortest path segment"), + "unifysegment", &wr, this, true) + , message(_("Note"), _("Important messages"), "message", &wr, this, + _("Add <b>\"Fill Between Many LPE\"</b> to add fill.")) +{ + registerParameter(&numberdashes); + registerParameter(&holefactor); + registerParameter(&splitsegments); + registerParameter(&halfextreme); + registerParameter(&unifysegment); + registerParameter(&message); + numberdashes.param_set_range(2, 999999999); + numberdashes.param_set_increments(1, 1); + numberdashes.param_set_digits(0); + holefactor.param_set_range(-0.99999, 0.99999); + holefactor.param_set_increments(0.01, 0.01); + holefactor.param_set_digits(5); + message.param_set_min_height(30); +} + +LPEDashedStroke::~LPEDashedStroke() = default; + +void LPEDashedStroke::doBeforeEffect(SPLPEItem const *lpeitem) {} + +///Calculate the time in curve_in with a real time of A +//TODO: find a better place to it +double LPEDashedStroke::timeAtLength(double const A, Geom::Path const &segment) +{ + if ( A == 0 || segment[0].isDegenerate()) { + return 0; + } + double t = 1; + t = timeAtLength(A, segment.toPwSb()); + return t; +} + +///Calculate the time in curve_in with a real time of A +//TODO: find a better place to it +double LPEDashedStroke::timeAtLength(double const A, Geom::Piecewise<Geom::D2<Geom::SBasis>> pwd2) +{ + if ( A == 0 || pwd2.size() == 0) { + return 0; + } + + double t = pwd2.size(); + std::vector<double> t_roots = roots(Geom::arcLengthSb(pwd2) - A); + if (!t_roots.empty()) { + t = t_roots[0]; + } + return t; +} + +Geom::PathVector LPEDashedStroke::doEffect_path(Geom::PathVector const &path_in) +{ + Geom::PathVector const pv = pathv_to_linear_and_cubic_beziers(path_in); + Geom::PathVector result; + for (const auto & path_it : pv) { + if (path_it.empty()) { + continue; + } + Geom::Path::const_iterator curve_it1 = path_it.begin(); + Geom::Path::const_iterator curve_it2 = ++(path_it.begin()); + Geom::Path::const_iterator curve_endit = path_it.end_default(); + if (path_it.closed()) { + const Geom::Curve &closingline = path_it.back_closed(); + // the closing line segment is always of type + // Geom::LineSegment. + if (are_near(closingline.initialPoint(), closingline.finalPoint())) { + // closingline.isDegenerate() did not work, because it only checks for + // *exact* zero length, which goes wrong for relative coordinates and + // rounding errors... + // the closing line segment has zero-length. So stop before that one! + curve_endit = path_it.end_open(); + } + } + size_t numberdashes_fixed = numberdashes; + if(!splitsegments) { + numberdashes_fixed++; + } + size_t numberholes = numberdashes_fixed - 1; + size_t ammount = numberdashes_fixed + numberholes; + if (halfextreme) { + ammount--; + } + double base = 1/(double)ammount; + double globaldash = base * numberdashes_fixed * (1 + holefactor); + if (halfextreme) { + globaldash = base * (numberdashes_fixed - 1) * (1 + holefactor); + } + double globalhole = 1-globaldash; + double dashpercent = globaldash/numberdashes_fixed; + if (halfextreme) { + dashpercent = globaldash/(numberdashes_fixed -1); + } + double holepercent = globalhole/numberholes; + double dashsize_fixed = 0; + double holesize_fixed = 0; + Geom::Piecewise<Geom::D2<Geom::SBasis> > pwd2 = path_it.toPwSb(); + double length_pwd2 = length (pwd2); + double minlength = length_pwd2; + if(unifysegment) { + while (curve_it1 != curve_endit) { + double length_segment = (*curve_it1).length(); + if (length_segment < minlength) { + minlength = length_segment; + dashsize_fixed = (*curve_it1).length() * dashpercent; + holesize_fixed = (*curve_it1).length() * holepercent; + } + ++curve_it1; + ++curve_it2; + } + curve_it1 = path_it.begin(); + curve_it2 = ++(path_it.begin()); + curve_endit = path_it.end_default(); + } + size_t p_index = 0; + size_t start_index = result.size(); + if(splitsegments) { + while (curve_it1 != curve_endit) { + Geom::Path segment = path_it.portion(p_index, p_index + 1); + if(unifysegment) { + double integral; + modf((*curve_it1).length()/(dashsize_fixed + holesize_fixed), &integral); + numberdashes_fixed = (size_t)integral + 1; + numberholes = numberdashes_fixed - 1; + ammount = numberdashes_fixed + numberholes; + if (halfextreme) { + ammount--; + } + base = 1/(double)ammount; + globaldash = base * numberdashes_fixed * (1 + holefactor); + if (halfextreme) { + globaldash = base * (numberdashes_fixed - 1) * (1 + holefactor); + } + globalhole = 1-globaldash; + dashpercent = globaldash/numberdashes_fixed; + if (halfextreme) { + dashpercent = globaldash/(numberdashes_fixed -1); + } + holepercent = globalhole/numberholes; + } + double dashsize = (*curve_it1).length() * dashpercent; + double holesize = (*curve_it1).length() * holepercent; + if ((*curve_it1).isLineSegment()) { + if (result.size() && Geom::are_near(segment.initialPoint(),result[result.size()-1].finalPoint())) { + result[result.size()-1].setFinal(segment.initialPoint()); + if (halfextreme) { + result[result.size()-1].append(segment.portion(0.0, dashpercent/2.0)); + } else { + result[result.size()-1].append(segment.portion(0.0, dashpercent)); + } + } else { + if (halfextreme) { + result.push_back(segment.portion(0.0, dashpercent/2.0)); + } else { + result.push_back(segment.portion(0.0, dashpercent)); + } + } + + double start = dashpercent + holepercent; + if (halfextreme) { + start = (dashpercent/2.0) + holepercent; + } + while (start < 1) { + if (start + dashpercent > 1) { + result.push_back(segment.portion(start, 1)); + } else { + result.push_back(segment.portion(start, start + dashpercent)); + } + start += dashpercent + holepercent; + } + } else if (!(*curve_it1).isLineSegment()) { + double start = 0.0; + double end = 0.0; + if (halfextreme) { + end = timeAtLength(dashsize/2.0,segment); + } else { + end = timeAtLength(dashsize,segment); + } + if (result.size() && Geom::are_near(segment.initialPoint(),result[result.size()-1].finalPoint())) { + result[result.size()-1].setFinal(segment.initialPoint()); + result[result.size()-1].append(segment.portion(start, end)); + } else { + result.push_back(segment.portion(start, end)); + } + double startsize = dashsize + holesize; + if (halfextreme) { + startsize = (dashsize/2.0) + holesize; + } + double endsize = startsize + dashsize; + start = timeAtLength(startsize,segment); + end = timeAtLength(endsize,segment); + while (start < 1 && start > 0) { + result.push_back(segment.portion(start, end)); + startsize = endsize + holesize; + endsize = startsize + dashsize; + start = timeAtLength(startsize,segment); + end = timeAtLength(endsize,segment); + } + } + if (curve_it2 == curve_endit) { + if (path_it.closed()) { + Geom::Path end = result[result.size()-1]; + end.setFinal(result[start_index].initialPoint()); + end.append(result[start_index]); + result[start_index] = end; + } + } + p_index ++; + ++curve_it1; + ++curve_it2; + } + } else { + double start = 0.0; + double end = 0.0; + double dashsize = length_pwd2 * dashpercent; + double holesize = length_pwd2 * holepercent; + if (halfextreme) { + end = timeAtLength(dashsize/2.0,pwd2); + } else { + end = timeAtLength(dashsize,pwd2); + } + result.push_back(path_it.portion(start, end)); + double startsize = dashsize + holesize; + if (halfextreme) { + startsize = (dashsize/2.0) + holesize; + } + double endsize = startsize + dashsize; + start = timeAtLength(startsize,pwd2); + end = timeAtLength(endsize,pwd2); + while (start < path_it.size() && start > 0) { + result.push_back(path_it.portion(start, end)); + startsize = endsize + holesize; + endsize = startsize + dashsize; + start = timeAtLength(startsize,pwd2); + end = timeAtLength(endsize,pwd2); + } + if (path_it.closed()) { + Geom::Path end = result[result.size()-1]; + end.setFinal(result[start_index].initialPoint()); + end.append(result[start_index]); + result[start_index] = end; + } + } + } + return result; +} + +}; //namespace LivePathEffect +}; /* namespace Inkscape */ + +/* + 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 : |