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/**
* elliptics via C-curves. (njh)
* Limited to 180 degrees (by end point and tangent matching criteria)
* Also represents cycloids
*/
#include <2geom/d2.h>
#include <2geom/sbasis.h>
#include <2geom/bezier-to-sbasis.h>
#include <2geom/sbasis-to-bezier.h>
#include <2geom/sbasis-math.h>
#include <toys/path-cairo.h>
#include <toys/toy-framework-2.h>
using std::vector;
using namespace Geom;
Linear z0(0.5,1.);
unsigned total_pieces;
double sinC(double t) { return t - sin(t);}
double cosC(double t) { return 1 - cos(t);}
double tanC(double t) { return sinC(t) / cosC(t);}
class Conic3: public Toy {
PointSetHandle psh;
public:
Conic3 () {
psh.push_back(100, 500);
psh.push_back(100, 500 - 200*M_PI/2);
psh.push_back(500, 500 - 200*M_PI/2);
psh.push_back(500, 500);
handles.push_back(&psh);
}
void draw(cairo_t *cr, std::ostringstream *notify, int width, int height, bool save, std::ostringstream *timer_stream) override {
cairo_set_source_rgba (cr, 0., 0., 0, 0.8);
cairo_set_line_width (cr, 0.5);
cairo_stroke(cr);
Geom::Point a[2] = {psh.pts[0] - psh.pts[1],
psh.pts[2] - psh.pts[1]};
double angle = Geom::angle_between(a[0], a[1]);
double len = std::max(Geom::L2(a[0]),
Geom::L2(a[1]));
for(auto & i : a)
i = len*unit_vector(i);
*notify << "angle = " << angle;
*notify << " sinC = " << sinC(angle);
*notify << " cosC = " << cosC(angle);
*notify << " tanC = " << tanC(angle);
vector<Geom::Point> e_a_h = psh.pts;
double alpha = M_PI;
Piecewise<SBasis> pw(Linear(0, alpha));
Piecewise<SBasis> C = cos(pw);
Piecewise<SBasis> S = sin(pw);
Piecewise<SBasis> sinC = pw - S;
Piecewise<SBasis> cosC = Piecewise<SBasis>(1) - C;
Piecewise<SBasis> Z3 = sinC/sinC(1);
Piecewise<SBasis> Z0 = reverse(Z3);
Piecewise<SBasis> Z2 = cosC/cosC(1) - Z3;
Piecewise<SBasis> Z1 = reverse(Z2);
Piecewise<SBasis> Z[4] = {Z0, Z1, Z2, Z3};
D2<Piecewise<SBasis> > B;
for(unsigned dim = 0; dim < 2; dim++) {
B[dim] = Piecewise<SBasis>(0);
for(unsigned i = 0; i < 4; i++) {
B[dim] += Z[i]*e_a_h[i][dim];
}
}
cairo_d2_pw_sb(cr, B);
Toy::draw(cr, notify, width, height, save,timer_stream);
}
};
int main(int argc, char **argv) {
init(argc, argv, new Conic3());
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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