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index a82da903bb4c7168ccb5f6b19e19b66057c4800a..bd9c0ca68b1c12a038bd78c6391ec1fc4164cdce 100644 (file)
*/
/*
* Authors:
- * Johan Engelen
+ * JF Barraud
*
-* Copyright (C) Johan Engelen 2007 <j.b.c.engelen@utwente.nl>
+* Copyright (C) JF Barraud 2007 <jf.barraud@gmail.com>
*
* Released under GNU GPL, read the file 'COPYING' for more information
*/
#include "display/curve.h"
#include <libnr/n-art-bpath.h>
-// You might need to include other 2geom files. You can add them here:
#include <2geom/path.h>
-#include <2geom/sbasis.h>
-#include <2geom/sbasis-geometric.h>
-#include <2geom/bezier-to-sbasis.h>
-#include <2geom/sbasis-to-bezier.h>
+//#include <2geom/sbasis.h>
+//#include <2geom/sbasis-geometric.h>
+//#include <2geom/bezier-to-sbasis.h>
+//#include <2geom/sbasis-to-bezier.h>
#include <2geom/d2.h>
-#include <2geom/sbasis-math.h>
-#include <2geom/piecewise.h>
+//#include <2geom/sbasis-math.h>
+//#include <2geom/piecewise.h>
#include <2geom/crossing.h>
#include <2geom/path-intersection.h>
}
-
-/* ########################
- * Choose to implement one of the doEffect functions. You can delete or comment out the others.
-*/
-
-/*
-void
-LPEKnot::doEffect (SPCurve * curve)
-{
- // spice this up to make the effect actually *do* something!
-}
-
-NArtBpath *
-LPEKnot::doEffect_nartbpath (NArtBpath * path_in)
-{
- NArtBpath *path_out;
- unsigned ret = 0;
- while ( path_in[ret].code != NR_END ) {
- ++ret;
- }
- unsigned len = ++ret;
- path_out = g_new(NArtBpath, len);
-
- memcpy(path_out, path_in, len * sizeof(NArtBpath)); // spice this up to make the effect actually *do* something!
-
- return path_out;
-}
-*/
-
+//remove an interval from an union of intervals.
std::vector<Geom::Interval> complementOf(Geom::Interval I, std::vector<Geom::Interval> domain){
std::vector<Geom::Interval> ret;
double min = domain.front().min();
return Interval(tmin,tmax);
}
+//Just a try; this should be moved to 2geom if ever it works.
+std::vector<Geom::Path>
+split_loopy_bezier (std::vector<Geom::Path> & path_in){
+
+ std::vector<Geom::Path> ret;
+ std::vector<Geom::Path>::iterator pi=path_in.begin();
+ for(; pi != path_in.end(); pi++) {
+ ret.push_back(Geom::Path());
+ for (Geom::Path::iterator curve(pi->begin()),end(pi->end()); curve != end; ++curve){
+
+ //is the current curve a cubic bezier?
+ if(Geom::CubicBezier const *cubic_bezier = dynamic_cast<Geom::CubicBezier const *>(&(*curve))){
+ Geom::CubicBezier theCurve = *cubic_bezier;
+ std::vector<Geom::Point> A = theCurve.points();
+
+ //is there a crossing in the polygon?
+ if( cross(A[2]-A[0],A[1]-A[0])*cross(A[3]-A[0],A[1]-A[0])<0 &&
+ cross(A[0]-A[3],A[2]-A[3])*cross(A[1]-A[3],A[2]-A[3])<0){
+
+ //split the curve where the tangent is parallel to the chord through end points.
+ double a = cross(A[3]-A[0],A[1]-A[2]);
+ double c = cross(A[3]-A[0],A[1]-A[0]);
+ double t; //where to split; solution of 3*at^2-(a+c)t +c = 0.
+ //TODO: don't we have a clean deg 2 equation solver?...
+ if (fabs(a)<.0001){
+ t = .5;
+ }else{
+ double delta = a*a-a*c+c*c;
+ t = ((a+c)-sqrt(delta))/2/a;
+ if ( t<0 || t>1 ) {t = ((a+c)+sqrt(delta))/2/a;}
+ }
+ //TODO: shouldn't Path have subdivide method?
+ std::pair<Geom::BezierCurve<3>, Geom::BezierCurve<3> > splitCurve;
+ splitCurve = theCurve.subdivide(t);
+ ret.back().append(splitCurve.first);
+ ret.back().append(splitCurve.second);
+
+ }else{//cubic bezier but no crossing.
+ ret.back().append(*curve);
+ }
+ }else{//not cubic bezier.
+ ret.back().append(*curve);
+ }
+ }
+ }
+ return ret;
+}
+
std::vector<Geom::Path>
LPEKnot::doEffect_path (std::vector<Geom::Path> & path_in)
std::vector<Geom::Path> path_out;
double width = interruption_width;
+ path_in = split_loopy_bezier(path_in);
+
CrossingSet crossingTable = crossings_among(path_in);
for (unsigned i = 0; i < crossingTable.size(); i++){
std::vector<Interval> dom;
assert(dom.at(comp).min() >=0 and dom.at(comp).max() < path_in.at(i).size());
path_out.push_back(path_in.at(i).portion(dom.at(comp)));
}
-
-// std::vector<Point> MV = path_in[0][0].pointAndDerivatives(crossingTable[0][0].getTime(0),2);
-// Point U = unit_vector(MV[1]);
-// Point N = U.cw();
-// Point A = MV[0]-10.*width*U, B = MV[0]+10*width*U;
-
-// Geom::Path cutter;
-// cutter = Geom::Path();
-// cutter.append( LineSegment(A+width*N,B+width*N));
-// path_out.push_back(cutter);
-// cutter = Geom::Path();
-// cutter.append( LineSegment(A-width*N,B-width*N));
-// path_out.push_back(cutter);
-
}
return path_out;
}