summaryrefslogtreecommitdiffstats
path: root/src/live_effects/lpe-bendpath.cpp
diff options
context:
space:
mode:
Diffstat (limited to 'src/live_effects/lpe-bendpath.cpp')
-rw-r--r--src/live_effects/lpe-bendpath.cpp300
1 files changed, 300 insertions, 0 deletions
diff --git a/src/live_effects/lpe-bendpath.cpp b/src/live_effects/lpe-bendpath.cpp
new file mode 100644
index 0000000..9aaeeff
--- /dev/null
+++ b/src/live_effects/lpe-bendpath.cpp
@@ -0,0 +1,300 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (C) Johan Engelen 2007 <j.b.c.engelen@utwente.nl>
+ * Copyright (C) Steren Giannini 2008 <steren.giannini@gmail.com>
+ *
+ * Released under GNU GPL v2+, read the file 'COPYING' for more information.
+ */
+
+#include <vector>
+
+#include "display/curve.h"
+#include "live_effects/lpe-bendpath.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>
+
+/* Theory in e-mail from J.F. Barraud
+Let B be the skeleton path, and P the pattern (the path to be deformed).
+
+P is a map t --> P(t) = ( x(t), y(t) ).
+B is a map t --> B(t) = ( a(t), b(t) ).
+
+The first step is to re-parametrize B by its arc length: this is the parametrization in which a point p on B is located by its distance s from start. One obtains a new map s --> U(s) = (a'(s),b'(s)), that still describes the same path B, but where the distance along B from start to
+U(s) is s itself.
+
+We also need a unit normal to the path. This can be obtained by computing a unit tangent vector, and rotate it by 90�. Call this normal vector N(s).
+
+The basic deformation associated to B is then given by:
+
+ (x,y) --> U(x)+y*N(x)
+
+(i.e. we go for distance x along the path, and then for distance y along the normal)
+
+Of course this formula needs some minor adaptations (as is it depends on the absolute position of P for instance, so a little translation is needed
+first) but I think we can first forget about them.
+*/
+
+namespace Inkscape {
+namespace LivePathEffect {
+
+namespace BeP {
+class KnotHolderEntityWidthBendPath : public LPEKnotHolderEntity {
+ public:
+ KnotHolderEntityWidthBendPath(LPEBendPath * effect) : LPEKnotHolderEntity(effect) {}
+ ~KnotHolderEntityWidthBendPath() override
+ {
+ LPEBendPath *lpe = dynamic_cast<LPEBendPath *> (_effect);
+ lpe->_knot_entity = nullptr;
+ }
+ void knot_set(Geom::Point const &p, Geom::Point const &origin, guint state) override;
+ Geom::Point knot_get() const override;
+ };
+} // BeP
+
+LPEBendPath::LPEBendPath(LivePathEffectObject *lpeobject) :
+ Effect(lpeobject),
+ bend_path(_("Bend path:"), _("Path along which to bend the original path"), "bendpath", &wr, this, "M0,0 L1,0"),
+ original_height(0.0),
+ prop_scale(_("_Width:"), _("Width of the path"), "prop_scale", &wr, this, 1.0),
+ scale_y_rel(_("W_idth in units of length"), _("Scale the width of the path in units of its length"), "scale_y_rel", &wr, this, false),
+ vertical_pattern(_("_Original path is vertical"), _("Rotates the original 90 degrees, before bending it along the bend path"), "vertical", &wr, this, false),
+ hide_knot(_("Hide width knot"), _("Hide width knot"),"hide_knot", &wr, this, false)
+{
+ registerParameter( &bend_path );
+ registerParameter( &prop_scale);
+ registerParameter( &scale_y_rel);
+ registerParameter( &vertical_pattern);
+ registerParameter(&hide_knot);
+
+ prop_scale.param_set_digits(3);
+ prop_scale.param_set_increments(0.01, 0.10);
+
+ _knot_entity = nullptr;
+ _provides_knotholder_entities = true;
+ apply_to_clippath_and_mask = true;
+ concatenate_before_pwd2 = true;
+}
+
+LPEBendPath::~LPEBendPath()
+= default;
+
+
+bool
+LPEBendPath::doOnOpen(SPLPEItem const *lpeitem)
+{
+ if (!is_load || is_applied) {
+ return false;
+ }
+ bend_path.reload();
+ return false;
+}
+
+
+void
+LPEBendPath::doBeforeEffect (SPLPEItem const* lpeitem)
+{
+ // get the item bounding box
+ original_bbox(lpeitem, false, true);
+ original_height = boundingbox_Y.max() - boundingbox_Y.min();
+ if (is_load) {
+ bend_path.reload();
+ }
+ if (_knot_entity) {
+ if (hide_knot) {
+ helper_path.clear();
+ _knot_entity->knot->hide();
+ } else {
+ _knot_entity->knot->show();
+ }
+ _knot_entity->update_knot();
+ }
+}
+
+void LPEBendPath::transform_multiply(Geom::Affine const &postmul, bool /*set*/)
+{
+ Inkscape::Selection * selection = nullptr;
+ SPItem *linked = nullptr;
+ if (SP_ACTIVE_DESKTOP) {
+ selection = SP_ACTIVE_DESKTOP->getSelection();
+ linked = dynamic_cast<SPItem *>(bend_path.getObject());
+ }
+ if (linked) {
+ linked->requestDisplayUpdate(SP_OBJECT_MODIFIED_FLAG);
+ return;
+ }
+ if (sp_lpe_item && sp_lpe_item->pathEffectsEnabled() && sp_lpe_item->optimizeTransforms()) {
+ bend_path.param_transform_multiply(postmul, false);
+ } else if( //this allow transform user spected way when lpeitem and pathparamenter are both selected
+ sp_lpe_item &&
+ sp_lpe_item->pathEffectsEnabled() &&
+ linked &&
+ (selection->includes(linked)))
+ {
+ Geom::Affine transformlpeitem = sp_item_transform_repr(sp_lpe_item).inverse() * postmul;
+ sp_lpe_item->transform *= transformlpeitem.inverse();
+ sp_lpe_item->requestDisplayUpdate(SP_OBJECT_MODIFIED_FLAG);
+ }
+}
+
+Geom::Piecewise<Geom::D2<Geom::SBasis> >
+LPEBendPath::doEffect_pwd2 (Geom::Piecewise<Geom::D2<Geom::SBasis> > const & pwd2_in)
+{
+ using namespace Geom;
+
+ /* Much credit should go to jfb and mgsloan of lib2geom development for the code below! */
+ Geom::Affine affine = bend_path.get_relative_affine();
+
+ if (bend_path.changed) {
+ uskeleton = arc_length_parametrization(Piecewise<D2<SBasis> >(bend_path.get_pwd2() * affine),2,.1);
+ uskeleton = remove_short_cuts(uskeleton,.01);
+ n = rot90(derivative(uskeleton));
+ n = force_continuity(remove_short_cuts(n,.01));
+
+ bend_path.changed = false;
+ }
+
+ if (uskeleton.empty()) {
+ return pwd2_in; /// \todo or throw an exception instead? might be better to throw an exception so that the UI can display an error message or smth
+ }
+
+ D2<Piecewise<SBasis> > patternd2 = make_cuts_independent(pwd2_in);
+ Piecewise<SBasis> x = vertical_pattern.get_value() ? Piecewise<SBasis>(patternd2[1]) : Piecewise<SBasis>(patternd2[0]);
+ Piecewise<SBasis> y = vertical_pattern.get_value() ? Piecewise<SBasis>(patternd2[0]) : Piecewise<SBasis>(patternd2[1]);
+
+ Interval bboxHorizontal = vertical_pattern.get_value() ? boundingbox_Y : boundingbox_X;
+ Interval bboxVertical = vertical_pattern.get_value() ? boundingbox_X : boundingbox_Y;
+
+ //+0.1 in x fix bug #1658855
+ //We use the group bounding box size or the path bbox size to translate well x and y
+ x-= bboxHorizontal.min() + 0.1;
+ y-= bboxVertical.middle();
+
+ double scaling = uskeleton.cuts.back()/bboxHorizontal.extent();
+
+ if (scaling != 1.0) {
+ x*=scaling;
+ }
+
+ if ( scale_y_rel.get_value() ) {
+ y*=(scaling*prop_scale);
+ } else {
+ if (prop_scale != 1.0) y *= prop_scale;
+ }
+
+ Piecewise<D2<SBasis> > output = compose(uskeleton,x) + y*compose(n,x);
+ return output;
+}
+
+void
+LPEBendPath::resetDefaults(SPItem const* item)
+{
+ Effect::resetDefaults(item);
+ original_bbox(SP_LPE_ITEM(item), false, true);
+
+ Geom::Point start(boundingbox_X.min(), (boundingbox_Y.max()+boundingbox_Y.min())/2);
+ Geom::Point end(boundingbox_X.max(), (boundingbox_Y.max()+boundingbox_Y.min())/2);
+
+ if ( Geom::are_near(start,end) ) {
+ end += Geom::Point(1.,0.);
+ }
+
+ Geom::Path path;
+ path.start( start );
+ path.appendNew<Geom::LineSegment>( end );
+ bend_path.set_new_value( path.toPwSb(), true );
+}
+
+void
+LPEBendPath::addCanvasIndicators(SPLPEItem const */*lpeitem*/, std::vector<Geom::PathVector> &hp_vec)
+{
+ hp_vec.push_back(helper_path);
+}
+
+void
+LPEBendPath::addKnotHolderEntities(KnotHolder *knotholder, SPItem *item)
+{
+ _knot_entity = new BeP::KnotHolderEntityWidthBendPath(this);
+ _knot_entity->create(nullptr, item, knotholder, Inkscape::CANVAS_ITEM_CTRL_TYPE_LPE, "LPE:WidthBend",
+ _("Change the width"));
+ knotholder->add(_knot_entity);
+ if (hide_knot) {
+ _knot_entity->knot->hide();
+ _knot_entity->update_knot();
+ }
+}
+
+namespace BeP {
+
+void
+KnotHolderEntityWidthBendPath::knot_set(Geom::Point const &p, Geom::Point const& /*origin*/, guint state)
+{
+ LPEBendPath *lpe = dynamic_cast<LPEBendPath *> (_effect);
+
+ Geom::Point const s = snap_knot_position(p, state);
+ Geom::Path path_in = lpe->bend_path.get_pathvector().pathAt(Geom::PathVectorTime(0, 0, 0.0));
+ Geom::Point ptA = path_in.pointAt(Geom::PathTime(0, 0.0));
+ Geom::Point B = path_in.pointAt(Geom::PathTime(1, 0.0));
+ Geom::Curve const *first_curve = &path_in.curveAt(Geom::PathTime(0, 0.0));
+ Geom::CubicBezier const *cubic = dynamic_cast<Geom::CubicBezier const *>(&*first_curve);
+ Geom::Ray ray(ptA, B);
+ if (cubic) {
+ ray.setPoints(ptA, (*cubic)[1]);
+ }
+ ray.setAngle(ray.angle() + Geom::rad_from_deg(90));
+ Geom::Point knot_pos = this->knot->pos * item->i2dt_affine().inverse();
+ Geom::Coord nearest_to_ray = ray.nearestTime(knot_pos);
+ if(nearest_to_ray == 0){
+ lpe->prop_scale.param_set_value(-Geom::distance(s , ptA)/(lpe->original_height/2.0));
+ } else {
+ lpe->prop_scale.param_set_value(Geom::distance(s , ptA)/(lpe->original_height/2.0));
+ }
+ if (!lpe->original_height) {
+ lpe->prop_scale.param_set_value(0);
+ }
+ Inkscape::Preferences *prefs = Inkscape::Preferences::get();
+ prefs->setDouble("/live_effects/bend_path/width", lpe->prop_scale);
+
+ sp_lpe_item_update_patheffect (SP_LPE_ITEM(item), false, true);
+}
+
+Geom::Point
+KnotHolderEntityWidthBendPath::knot_get() const
+{
+ LPEBendPath *lpe = dynamic_cast<LPEBendPath *> (_effect);
+ Geom::Path path_in = lpe->bend_path.get_pathvector().pathAt(Geom::PathVectorTime(0, 0, 0.0));
+ Geom::Point ptA = path_in.pointAt(Geom::PathTime(0, 0.0));
+ Geom::Point B = path_in.pointAt(Geom::PathTime(1, 0.0));
+ Geom::Curve const *first_curve = &path_in.curveAt(Geom::PathTime(0, 0.0));
+ Geom::CubicBezier const *cubic = dynamic_cast<Geom::CubicBezier const *>(&*first_curve);
+ Geom::Ray ray(ptA, B);
+ if (cubic) {
+ ray.setPoints(ptA, (*cubic)[1]);
+ }
+ ray.setAngle(ray.angle() + Geom::rad_from_deg(90));
+ Geom::Point result_point = Geom::Point::polar(ray.angle(), (lpe->original_height/2.0) * lpe->prop_scale) + ptA;
+ lpe->helper_path.clear();
+ if (!lpe->hide_knot) {
+ Geom::Path hp(result_point);
+ hp.appendNew<Geom::LineSegment>(ptA);
+ lpe->helper_path.push_back(hp);
+ hp.clear();
+ }
+ return result_point;
+}
+} // namespace BeP
+} // 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 :