diff options
Diffstat (limited to 'src/live_effects/lpe-tangent_to_curve.cpp')
| -rw-r--r-- | src/live_effects/lpe-tangent_to_curve.cpp | 206 |
1 files changed, 206 insertions, 0 deletions
diff --git a/src/live_effects/lpe-tangent_to_curve.cpp b/src/live_effects/lpe-tangent_to_curve.cpp new file mode 100644 index 0000000..62f5fcb --- /dev/null +++ b/src/live_effects/lpe-tangent_to_curve.cpp @@ -0,0 +1,206 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/** \file + * Implementation of tangent-to-curve LPE. + */ + +/* + * Authors: + * Johan Engelen + * Maximilian Albert + * + * Copyright (C) Johan Engelen 2007 <j.b.c.engelen@utwente.nl> + * Copyright (C) Maximilian Albert 2008 <maximilian.albert@gmail.com> + * + * Released under GNU GPL v2+, read the file 'COPYING' for more information. + */ + +#include "lpe-tangent_to_curve.h" + +#include "display/curve.h" + +#include "object/sp-shape.h" +#include "object/sp-object-group.h" +#include "ui/knot/knot-holder.h" +#include "ui/knot/knot-holder-entity.h" + +// TODO due to internal breakage in glibmm headers, this must be last: +#include <glibmm/i18n.h> + +namespace Inkscape { +namespace LivePathEffect { + +namespace TtC { + +class KnotHolderEntityAttachPt : public LPEKnotHolderEntity { +public: + KnotHolderEntityAttachPt(LPETangentToCurve *effect) : LPEKnotHolderEntity(effect) {}; + void knot_set(Geom::Point const &p, Geom::Point const &origin, guint state) override; + Geom::Point knot_get() const override; +}; + +class KnotHolderEntityLeftEnd : public LPEKnotHolderEntity { +public: + KnotHolderEntityLeftEnd(LPETangentToCurve *effect) : LPEKnotHolderEntity(effect) {}; + void knot_set(Geom::Point const &p, Geom::Point const &origin, guint state) override; + Geom::Point knot_get() const override; +}; + +class KnotHolderEntityRightEnd : public LPEKnotHolderEntity +{ +public: + KnotHolderEntityRightEnd(LPETangentToCurve *effect) : LPEKnotHolderEntity(effect) {}; + void knot_set(Geom::Point const &p, Geom::Point const &origin, guint state) override; + Geom::Point knot_get() const override; +}; + +} // namespace TtC + +LPETangentToCurve::LPETangentToCurve(LivePathEffectObject *lpeobject) : + Effect(lpeobject), + angle(_("Angle:"), _("Additional angle between tangent and curve"), "angle", &wr, this, 0.0), + t_attach(_("Location along curve:"), _("Location of the point of attachment along the curve (between 0.0 and number-of-segments)"), "t_attach", &wr, this, 0.5), + length_left(_("Length left:"), _("Specifies the left end of the tangent"), "length-left", &wr, this, 150), + length_right(_("Length right:"), _("Specifies the right end of the tangent"), "length-right", &wr, this, 150) +{ + show_orig_path = true; + _provides_knotholder_entities = true; + + registerParameter(&angle); + registerParameter(&t_attach); + registerParameter(&length_left); + registerParameter(&length_right); +} + +LPETangentToCurve::~LPETangentToCurve() += default; + +Geom::Piecewise<Geom::D2<Geom::SBasis> > +LPETangentToCurve::doEffect_pwd2 (Geom::Piecewise<Geom::D2<Geom::SBasis> > const & pwd2_in) +{ + using namespace Geom; + Piecewise<D2<SBasis> > output; + + ptA = pwd2_in.valueAt(t_attach); + derivA = unit_vector(derivative(pwd2_in).valueAt(t_attach)); + + // TODO: Why are positive angles measured clockwise, not counterclockwise? + Geom::Rotate rot(Geom::Rotate::from_degrees(-angle)); + derivA = derivA * rot; + + C = ptA - derivA * length_left; + D = ptA + derivA * length_right; + + output = Piecewise<D2<SBasis> >(D2<SBasis>(SBasis(C[X], D[X]), SBasis(C[Y], D[Y]))); + + return output; +} + +void +LPETangentToCurve::addKnotHolderEntities(KnotHolder *knotholder, SPItem *item) { + { + KnotHolderEntity *e = new TtC::KnotHolderEntityAttachPt(this); + e->create(nullptr, item, knotholder, Inkscape::CANVAS_ITEM_CTRL_TYPE_LPE, "LPE:TangentToCurvePT", + _("Adjust the point of attachment of the tangent")); + knotholder->add(e); + } + { + KnotHolderEntity *e = new TtC::KnotHolderEntityLeftEnd(this); + e->create(nullptr, item, knotholder, Inkscape::CANVAS_ITEM_CTRL_TYPE_LPE, "LPE:TangentToCurveLeftEnd", + _("Adjust the <b>left</b> end of the tangent")); + knotholder->add(e); + } + { + KnotHolderEntity *e = new TtC::KnotHolderEntityRightEnd(this); + e->create(nullptr, item, knotholder, Inkscape::CANVAS_ITEM_CTRL_TYPE_LPE, "LPE:TangetToCurveRightEnd", + _("Adjust the <b>right</b> end of the tangent")); + knotholder->add(e); + } +}; + +namespace TtC { + +void +KnotHolderEntityAttachPt::knot_set(Geom::Point const &p, Geom::Point const &/*origin*/, guint state) +{ + using namespace Geom; + + LPETangentToCurve* lpe = dynamic_cast<LPETangentToCurve *>(_effect); + + Geom::Point const s = snap_knot_position(p, state); + + if ( !SP_IS_SHAPE(lpe->sp_lpe_item) ) { + //lpe->t_attach.param_set_value(0); + g_warning("LPEItem is not a path! %s:%d\n", __FILE__, __LINE__); + return; + } + Piecewise<D2<SBasis> > pwd2 = paths_to_pw( lpe->pathvector_before_effect ); + + double t0 = nearest_time(s, pwd2); + lpe->t_attach.param_set_value(t0); + + // FIXME: this should not directly ask for updating the item. It should write to SVG, which triggers updating. + sp_lpe_item_update_patheffect (SP_LPE_ITEM(item), false, true); +} + +void +KnotHolderEntityLeftEnd::knot_set(Geom::Point const &p, Geom::Point const &/*origin*/, guint state) +{ + LPETangentToCurve *lpe = dynamic_cast<LPETangentToCurve *>(_effect); + + Geom::Point const s = snap_knot_position(p, state); + + double lambda = Geom::nearest_time(s, lpe->ptA, lpe->derivA); + lpe->length_left.param_set_value(-lambda); + + sp_lpe_item_update_patheffect (SP_LPE_ITEM(item), false, true); +} + +void +KnotHolderEntityRightEnd::knot_set(Geom::Point const &p, Geom::Point const &/*origin*/, guint state) +{ + LPETangentToCurve *lpe = dynamic_cast<LPETangentToCurve *>(_effect); + + Geom::Point const s = snap_knot_position(p, state); + + double lambda = Geom::nearest_time(s, lpe->ptA, lpe->derivA); + lpe->length_right.param_set_value(lambda); + + sp_lpe_item_update_patheffect (SP_LPE_ITEM(item), false, true); +} + +Geom::Point +KnotHolderEntityAttachPt::knot_get() const +{ + LPETangentToCurve const *lpe = dynamic_cast<LPETangentToCurve const*>(_effect); + return lpe->ptA; +} + +Geom::Point +KnotHolderEntityLeftEnd::knot_get() const +{ + LPETangentToCurve const *lpe = dynamic_cast<LPETangentToCurve const*>(_effect); + return lpe->C; +} + +Geom::Point +KnotHolderEntityRightEnd::knot_get() const +{ + LPETangentToCurve const *lpe = dynamic_cast<LPETangentToCurve const*>(_effect); + return lpe->D; +} + +} // namespace TtC + +} //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 : |