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#define INKSCAPE_LPE_BSPLINE_C
/*
* Released under GNU GPL, read the file 'COPYING' for more information
*/
#include "live_effects/lpe-bspline.h"
#include "display/curve.h"
#include <typeinfo>
#include <2geom/pathvector.h>
#include <2geom/affine.h>
#include <2geom/bezier-curve.h>
#include "helper/geom-curves.h"
// For handling un-continuous paths:
#include "message-stack.h"
#include "inkscape.h"
#include "desktop.h"
namespace Inkscape {
namespace LivePathEffect {
LPEBSpline::LPEBSpline(LivePathEffectObject *lpeobject) :
Effect(lpeobject)
{
}
LPEBSpline::~LPEBSpline()
{
}
void
LPEBSpline::doEffect(SPCurve * curve)
{
if(curve->get_segment_count() < 2)
return;
// Make copy of old path as it is changed during processing
Geom::PathVector const original_pathv = curve->get_pathvector();
curve->reset();
//Recorremos todos los paths a los que queremos aplicar el efecto, hasta el penúltimo
for(Geom::PathVector::const_iterator path_it = original_pathv.begin(); path_it != original_pathv.end(); ++path_it) {
//Si está vacío...
if (path_it->empty())
continue;
//Itreadores
Geom::Path::const_iterator curve_it1 = path_it->begin(); // incoming curve
Geom::Path::const_iterator curve_it2 = ++(path_it->begin()); // outgoing curve
Geom::Path::const_iterator curve_endit = path_it->end_default(); // this determines when the loop has to stop
//Creamos las lineas rectas que unen todos los puntos del trazado y donde se calcularán
//los puntos clave para los manejadores.
//Esto hace que la curva BSpline no pierda su condición aunque se trasladen
//dichos manejadores
SPCurve *nCurve = new SPCurve();
Geom::Point previousNode(0,0);
Geom::Point node(0,0);
Geom::Point pointAt1(0,0);
Geom::Point pointAt2(0,0);
Geom::Point nextPointAt1(0,0);
Geom::Point nextPointAt2(0,0);
Geom::Point nextPointAt3(0,0);
Geom::D2< Geom::SBasis > SBasisIn;
Geom::D2< Geom::SBasis > SBasisOut;
Geom::D2< Geom::SBasis > SBasisHelper;
Geom::CubicBezier const *cubic = NULL;
if (path_it->closed()) {
// if the path is closed, maybe we have to stop a bit earlier because the closing line segment has zerolength.
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();
}
}
//Si la curva está cerrada calculamos el punto donde
//deveria estar el nodo BSpline de cierre/inicio de la curva
//en posible caso de que se cierre con una linea recta creando un nodo BSPline
//Recorremos todos los segmentos menos el último
while ( curve_it2 != curve_endit )
{
//previousPointAt3 = pointAt3;
//Calculamos los puntos que dividirían en tres segmentos iguales el path recto de entrada y de salida
SPCurve * in = new SPCurve();
in->moveto(curve_it1->initialPoint());
in->lineto(curve_it1->finalPoint());
cubic = dynamic_cast<Geom::CubicBezier const*>(&*curve_it1);
if(cubic){
SBasisIn = in->first_segment()->toSBasis();
pointAt1 = SBasisIn.valueAt(Geom::nearest_point((*cubic)[1],*in->first_segment()));
pointAt2 = SBasisIn.valueAt(Geom::nearest_point((*cubic)[2],*in->first_segment()));
}else{
pointAt1 = in->first_segment()->initialPoint();
pointAt2 = in->first_segment()->finalPoint();
}
in->reset();
delete in;
//Y hacemos lo propio con el path de salida
//nextPointAt0 = curveOut.valueAt(0);
SPCurve * out = new SPCurve();
out->moveto(curve_it2->initialPoint());
out->lineto(curve_it2->finalPoint());
cubic = dynamic_cast<Geom::CubicBezier const*>(&*curve_it2);
if(cubic){
SBasisOut = out->first_segment()->toSBasis();
nextPointAt1 = SBasisOut.valueAt(Geom::nearest_point((*cubic)[1],*out->first_segment()));
nextPointAt2 = SBasisOut.valueAt(Geom::nearest_point((*cubic)[2],*out->first_segment()));;
nextPointAt3 = (*cubic)[3];
}else{
nextPointAt1 = out->first_segment()->initialPoint();
nextPointAt2 = out->first_segment()->finalPoint();
nextPointAt3 = out->first_segment()->finalPoint();
}
out->reset();
delete out;
//La curva BSpline se forma calculando el centro del segmanto de unión
//de el punto situado en las 2/3 partes de el segmento de entrada
//con el punto situado en la posición 1/3 del segmento de salida
//Estos dos puntos ademas estan posicionados en el lugas correspondiente de
//los manejadores de la curva
SPCurve *lineHelper = new SPCurve();
lineHelper->moveto(pointAt2);
lineHelper->lineto(nextPointAt1);
SBasisHelper = lineHelper->first_segment()->toSBasis();
lineHelper->reset();
delete lineHelper;
//almacenamos el punto del anterior bucle -o el de cierre- que nos hara de principio de curva
previousNode = node;
//Y este hará de final de curva
node = SBasisHelper.valueAt(0.5);
SPCurve *curveHelper = new SPCurve();
curveHelper->moveto(previousNode);
curveHelper->curveto(pointAt1, pointAt2, node);
//añadimos la curva generada a la curva pricipal
nCurve->append_continuous(curveHelper, 0.0625);
curveHelper->reset();
delete curveHelper;
//aumentamos los valores para el siguiente paso en el bucle
++curve_it1;
++curve_it2;
}
//Aberiguamos la ultima parte de la curva correspondiente al último segmento
SPCurve *curveHelper = new SPCurve();
curveHelper->moveto(node);
//Si está cerrada la curva, la cerramos sobre el valor guardado previamente
//Si no finalizamos en el punto final
Geom::Point startNode(0,0);
if (path_it->closed()) {
SPCurve * start = new SPCurve();
start->moveto(path_it->begin()->initialPoint());
start->lineto(path_it->begin()->finalPoint());
Geom::D2< Geom::SBasis > SBasisStart = start->first_segment()->toSBasis();
SPCurve *lineHelper = new SPCurve();
cubic = dynamic_cast<Geom::CubicBezier const*>(&*path_it->begin());
if(cubic){
lineHelper->moveto(SBasisStart.valueAt(Geom::nearest_point((*cubic)[1],*start->first_segment())));
}else{
lineHelper->moveto(start->first_segment()->initialPoint());
}
start->reset();
delete start;
SPCurve * end = new SPCurve();
end->moveto(curve_it1->initialPoint());
end->lineto(curve_it1->finalPoint());
Geom::D2< Geom::SBasis > SBasisEnd = end->first_segment()->toSBasis();
//Geom::BezierCurve const *bezier = dynamic_cast<Geom::BezierCurve const*>(&*curve_endit);
cubic = dynamic_cast<Geom::CubicBezier const*>(&*curve_it1);
if(cubic){
lineHelper->lineto(SBasisEnd.valueAt(Geom::nearest_point((*cubic)[2],*end->first_segment())));
}else{
lineHelper->lineto(end->first_segment()->finalPoint());
}
end->reset();
delete end;
SBasisHelper = lineHelper->first_segment()->toSBasis();
lineHelper->reset();
delete lineHelper;
//Guardamos el principio de la curva
startNode = SBasisHelper.valueAt(0.5);
curveHelper->curveto(nextPointAt1, nextPointAt2, startNode);
nCurve->append_continuous(curveHelper, 0.0625);
nCurve->move_endpoints(startNode,startNode);
}else{
SPCurve * start = new SPCurve();
start->moveto(path_it->begin()->initialPoint());
start->lineto(path_it->begin()->finalPoint());
startNode = start->first_segment()->initialPoint();
start->reset();
delete start;
curveHelper->curveto(nextPointAt1, nextPointAt2, nextPointAt3);
nCurve->append_continuous(curveHelper, 0.0625);
nCurve->move_endpoints(startNode,nextPointAt3);
}
curveHelper->reset();
delete curveHelper;
//y cerramos la curva
if (path_it->closed()) {
nCurve->closepath_current();
}
curve->append(nCurve,false);
nCurve->reset();
delete nCurve;
}
}
}; //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 :
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