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#include <2geom/d2.h>
#include <2geom/sbasis.h>
#include <2geom/sbasis-2d.h>
#include <2geom/bezier-to-sbasis.h>
#include <2geom/sbasis-geometric.h>
#include <toys/path-cairo.h>
#include <toys/toy-framework-2.h>
#include <time.h>
using std::vector;
using namespace Geom;
using namespace std;
// TODO:
// use path2
// replace Ray stuff with path2 line segments.
//-----------------------------------------------
class CurvatureTester: public Toy {
PointSetHandle curve_handle;
PointHandle sample_point;
void draw(cairo_t *cr, std::ostringstream *notify, int width, int height, bool save, std::ostringstream *timer_stream) override {
D2<SBasis> B = curve_handle.asBezier();
cairo_set_line_width (cr, 1);
cairo_set_source_rgba (cr, 0., 0.5, 0., 1);
cairo_d2_sb(cr, B);
cairo_stroke(cr);
sample_point.pos[1]=400;
sample_point.pos[0]=std::max(150.,sample_point.pos[0]);
sample_point.pos[0]=std::min(450.,sample_point.pos[0]);
cairo_move_to(cr, Geom::Point(150,400));
cairo_line_to(cr, Geom::Point(450,400));
cairo_set_source_rgba (cr, 0., 0., 0.5, 0.8);
cairo_stroke(cr);
double t=std::max(0.,std::min(1.,(sample_point.pos[0]-150)/300.));
Timer tm;
tm.ask_for_timeslice();
tm.start();
Piecewise<SBasis> K = curvature(B);
Timer::Time als_time = tm.lap();
*timer_stream << "curvature " << als_time << std::endl;
for(unsigned ix = 0; ix < K.segs.size(); ix++) {
D2<SBasis> Kxy;
Kxy[1] = Linear(400) - K.segs[ix]*300;
Kxy[0] = Linear(300*K.cuts[ix] + 150, 300*K.cuts[ix+1] + 150);
cairo_d2_sb(cr, Kxy);
cairo_stroke(cr);
}
double radius = K(t);
*notify<<"K="<<radius<<std::endl;
if (fabs(radius)>1e-4){
radius=1./radius;
Geom::Point normal=unit_vector(derivative(B)(t));
normal=rot90(normal);
Geom::Point center=B(t)-radius*normal;
cairo_arc(cr, center[0], center[1],fabs(radius), 0, M_PI*2);
draw_handle(cr, center);
draw_handle(cr, B(t));
}else{
Geom::Point p=B(t);
Geom::Point v=derivative(B)(t);
draw_handle(cr, p);
cairo_move_to(cr, p-100*v);
cairo_line_to(cr, p+100*v);
}
cairo_set_source_rgba (cr, 0.5, 0.2, 0., 0.8);
cairo_stroke(cr);
Toy::draw(cr, notify, width, height, save,timer_stream);
}
public:
CurvatureTester(){
if(handles.empty()) {
handles.push_back(&curve_handle);
handles.push_back(&sample_point);
for(unsigned i = 0; i < 4; i++)
curve_handle.push_back(150+uniform()*300,150+uniform()*300);
sample_point.pos = Geom::Point(250,300);
}
}
};
int main(int argc, char **argv) {
std::cout << "testing unit_normal(multidim_sbasis) based offset." << std::endl;
init(argc, argv, new CurvatureTester);
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:expandtab:shiftwidth = 4:tabstop = 8:softtabstop = 4:encoding = utf-8:textwidth = 99 :
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