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#include <2geom/d2.h>
#include <2geom/piecewise.h>
#include <2geom/sbasis.h>
#include <2geom/sbasis-geometric.h>
#include <2geom/bezier-to-sbasis.h>
#include <toys/path-cairo.h>
#include <toys/toy-framework-2.h>
#include <algorithm>
using std::vector;
using namespace Geom;
class PathAlongPathToy: public Toy {
PointSetHandle skel_handles, pat_handles;
PointHandle origin_handle;
bool should_draw_numbers() override{return false;}
void draw(cairo_t *cr, std::ostringstream *notify, int width, int height, bool save, std::ostringstream *timer_stream) override {
D2<SBasis> skeleton = skel_handles.asBezier();
D2<SBasis> pattern = pat_handles.asBezier();
cairo_set_line_width(cr,1.);
cairo_pw_d2_sb(cr, Piecewise<D2<SBasis> >(skeleton));
cairo_set_source_rgba(cr,0.0,0.0,1.0,1.0);
cairo_stroke(cr);
cairo_pw_d2_sb(cr, Piecewise<D2<SBasis> >(pattern));
cairo_set_source_rgba(cr,1.0,0.0,1.0,1.0);
cairo_stroke(cr);
origin_handle.pos[0]=150;
Geom::Point origin = origin_handle.pos;
Piecewise<D2<SBasis> > uskeleton = arc_length_parametrization(Piecewise<D2<SBasis> >(skeleton),2,.1);
uskeleton = remove_short_cuts(uskeleton,.01);
Piecewise<D2<SBasis> > n = rot90(derivative(uskeleton));
n = force_continuity(remove_short_cuts(n,.1));
Piecewise<SBasis> x=Piecewise<SBasis>(pattern[0]-origin[0]);
Piecewise<SBasis> y=Piecewise<SBasis>(pattern[1]-origin[1]);
Interval pattBnds = *bounds_exact(x);
int nbCopies = int(uskeleton.cuts.back()/pattBnds.extent());
//double pattWidth = uskeleton.cuts.back()/nbCopies;
double pattWidth = pattBnds.extent();
double offs = 0;
x-=pattBnds.min();
//x*=pattWidth/pattBnds.extent();
Piecewise<D2<SBasis> >output;
for (int i=0; i<nbCopies; i++){
output.concat(compose(uskeleton,x+offs)+y*compose(n,x+offs));
offs+=pattWidth;
}
//Perform cut for last segment
double tt = uskeleton.cuts.back() - offs;
if(tt > 0.) {
vector<double> rs = roots(x - tt);
rs.push_back(0); rs.push_back(1); //regard endpoints
std::sort(rs.begin(), rs.end());
std::unique(rs.begin(), rs.end());
//enumerate indices of sections to the left of the line
for(unsigned i = (x[0].at0()>tt ? 1 : 0); i < rs.size()-1; i+=2) {
Piecewise<SBasis> port = portion(x+offs, rs[i], rs[i+1]);
output.concat(compose(uskeleton,port)+portion(y, rs[i], rs[i+1])*compose(n,port));
}
}
cairo_pw_d2_sb(cr, output);
cairo_set_source_rgba(cr,1.0,0.0,1.0,1.0);
cairo_stroke(cr);
Toy::draw(cr, notify, width, height, save,timer_stream);
}
public:
PathAlongPathToy() : origin_handle(150,150) {
if(handles.empty()) {
handles.push_back(&skel_handles);
handles.push_back(&pat_handles);
for(int i = 0; i < 8; i++)
skel_handles.push_back(200+50*i,400);
for(int i = 0; i < 4; i++)
pat_handles.push_back(100+uniform()*400,
150+uniform()*100);
handles.push_back(&origin_handle);
}
}
};
int main(int argc, char **argv) {
init(argc, argv, new PathAlongPathToy);
return 0;
}
/*
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:fileencoding=utf-8:textwidth=99 :
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