lpe-perp_bisector.cpp revision 78f31011c08503bf0d95da30e5f6326d4dd10f8a
#define INKSCAPE_LPE_PERP_BISECTOR_CPP
/** \file
* LPE <perp_bisector> implementation.
*/
/*
* Authors:
* Maximilian Albert
* Johan Engelen
*
* Copyright (C) Johan Engelen 2007 <j.b.c.engelen@utwente.nl>
* Copyright (C) Maximilin Albert 2008 <maximilian.albert@gmail.com>
*
* Released under GNU GPL, read the file 'COPYING' for more information
*/
#include "live_effects/lpe-perp_bisector.h"
#include "display/curve.h"
#include <libnr/n-art-bpath.h>
#include "sp-path.h"
#include "line-geometry.h"
#include "sp-lpe-item.h"
#include <2geom/path.h>
namespace Inkscape {
namespace LivePathEffect {
/* FIXME: We should make these member functions of LPEPerpBisector.
Is there an easy way to register member functions with knotholder?
KNOWN BUG: Because of the above, this effect does not work well when in an LPE stack
*/
NR::Point bisector_left_end_get(SPItem *item) {
Inkscape::LivePathEffect::LPEPerpBisector *lpe =
dynamic_cast<Inkscape::LivePathEffect::LPEPerpBisector *> (sp_lpe_item_get_current_lpe(SP_LPE_ITEM(item)));
if (lpe)
return NR::Point(lpe->C);
else
return NR::Point(0,0);
}
NR::Point bisector_right_end_get(SPItem *item) {
Inkscape::LivePathEffect::LPEPerpBisector *lpe =
dynamic_cast<Inkscape::LivePathEffect::LPEPerpBisector *> (sp_lpe_item_get_current_lpe(SP_LPE_ITEM(item)));
if (lpe)
return NR::Point(lpe->D);
else
return NR::Point(0,0);
}
void
bisector_end_set(SPItem *item, NR::Point const &p, bool left) {
Inkscape::LivePathEffect::LPEPerpBisector *lpe =
dynamic_cast<Inkscape::LivePathEffect::LPEPerpBisector *> (sp_lpe_item_get_current_lpe(SP_LPE_ITEM(item)));
if (!lpe)
return;
double lambda = Geom::nearest_point(p.to_2geom(), lpe->M, lpe->perp_dir);
if (left) {
lpe->C = lpe->M + lpe->perp_dir * lambda;
lpe->length_left.param_set_value(lambda);
} else {
lpe->D = lpe->M + lpe->perp_dir * lambda;
lpe->length_right.param_set_value(-lambda);
}
// 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), true, true);
}
void
bisector_left_end_set(SPItem *item, NR::Point const &p, NR::Point const &/*origin*/, guint /*state*/) {
bisector_end_set(item, p);
}
void
bisector_right_end_set(SPItem *item, NR::Point const &p, NR::Point const &/*origin*/, guint /*state*/) {
bisector_end_set(item, p, false);
}
NR::Point path_start_get(SPItem *item) {
Inkscape::LivePathEffect::LPEPerpBisector *lpe =
dynamic_cast<Inkscape::LivePathEffect::LPEPerpBisector *> (sp_lpe_item_get_current_lpe(SP_LPE_ITEM(item)));
if (lpe)
return NR::Point(lpe->A);
else
return NR::Point(0,0);
}
NR::Point path_end_get(SPItem *item) {
Inkscape::LivePathEffect::LPEPerpBisector *lpe =
dynamic_cast<Inkscape::LivePathEffect::LPEPerpBisector *> (sp_lpe_item_get_current_lpe(SP_LPE_ITEM(item)));
if (lpe)
return NR::Point(lpe->B);
else
return NR::Point(0,0);
}
void
path_set_start_end(SPItem *item, NR::Point const &p, bool start) {
SPCurve* curve = sp_path_get_curve_for_edit (SP_PATH(item)); // TODO: Should we use sp_shape_get_curve()?
NR::Matrix const i2d (sp_item_i2d_affine (SP_ITEM(item)));
Geom::Point A, B;
if (start) {
A = p.to_2geom();
B = (curve->last_point()).to_2geom();
} else {
A = (curve->first_point()).to_2geom();
B = (p.to_2geom());
}
SPCurve *c = new SPCurve();
c->moveto(A);
c->lineto(B);
sp_path_set_original_curve(SP_PATH(item), c, TRUE, true);
c->unref();
}
void path_start_set(SPItem *item, NR::Point const &p, NR::Point const &/*origin*/, guint /*state*/) {
path_set_start_end(item, p);
}
void path_end_set(SPItem *item, NR::Point const &p, NR::Point const &/*origin*/, guint /*state*/) {
path_set_start_end(item, p, false);
}
LPEPerpBisector::LPEPerpBisector(LivePathEffectObject *lpeobject) :
Effect(lpeobject),
length_left(_("Length left"), _("Specifies the left end of the bisector"), "length-left", &wr, this, 200),
length_right(_("Length right"), _("Specifies the right end of the bisector"), "length-right", &wr, this, 200),
A(0,0), B(0,0), M(0,0), C(0,0), D(0,0), perp_dir(0,0)
{
// register all your parameters here, so Inkscape knows which parameters this effect has:
registerParameter( dynamic_cast<Parameter *>(&length_left) );
registerParameter( dynamic_cast<Parameter *>(&length_right) );
registerKnotHolderHandle(path_start_set, path_start_get);
registerKnotHolderHandle(path_end_set, path_end_get);
registerKnotHolderHandle(bisector_left_end_set, bisector_left_end_get);
registerKnotHolderHandle(bisector_right_end_set, bisector_right_end_get);
}
LPEPerpBisector::~LPEPerpBisector()
{
}
void
LPEPerpBisector::doOnApply (SPLPEItem *lpeitem)
{
/* make the path a straight line */
SPCurve* curve = sp_path_get_curve_for_edit (SP_PATH(lpeitem)); // TODO: Should we use sp_shape_get_curve()?
Geom::Point A((curve->first_point()).to_2geom());
Geom::Point B((curve->last_point()).to_2geom());
SPCurve *c = new SPCurve();
c->moveto(A);
c->lineto(B);
// TODO: Why doesn't sp_path_set_original_curve(SP_PATH(lpeitem), c, TRUE, true) work?
SP_PATH(lpeitem)->original_curve = c->ref();
c->unref();
}
Geom::Piecewise<Geom::D2<Geom::SBasis> >
LPEPerpBisector::doEffect_pwd2 (Geom::Piecewise<Geom::D2<Geom::SBasis> > const & pwd2_in)
{
using namespace Geom;
Piecewise<D2<SBasis> > output;
A = pwd2_in.firstValue();
B = pwd2_in.lastValue();
M = (A + B)/2;
perp_dir = unit_vector((B - A).ccw());
C = M + perp_dir * length_left;
D = M - perp_dir * length_right;
output = Piecewise<D2<SBasis> >(D2<SBasis>(Linear(C[X], D[X]), Linear(C[Y], D[Y])));
return output;
}
/* ######################## */
} //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 :