1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
|
#include <2geom/d2.h>
#include <2geom/sbasis.h>
#include <toys/path-cairo.h>
#include <toys/toy-framework-2.h>
using namespace Geom;
#define SIZE 4
class SBZeros: public Toy {
PointSetHandle pB1, pB2;
void draw(cairo_t *cr, std::ostringstream *notify, int width, int height, bool save, std::ostringstream *timer_stream) override {
D2<SBasis> B1 = pB1.asBezier();
D2<SBasis> B2 = pB2.asBezier();
Piecewise<D2<SBasis> >B;
B.concat(Piecewise<D2<SBasis> >(B1));
B.concat(Piecewise<D2<SBasis> >(B2));
std::vector<Point> e;
std::vector<Piecewise<D2<SBasis> > > s;
s.push_back(derivative(B));
for(int j = 0; j < 5; j++) s.push_back(derivative(s.back()));
for(int j = 0; j <= 5; j++) {
for(unsigned d = 0; d < 2; d++) {
std::vector<double> r = roots(make_cuts_independent(s[j])[d]);
for(double k : r) e.push_back(B.valueAt(k));
}
}
for(auto & i : e) draw_cross(cr, i);
cairo_set_line_width (cr, .5);
cairo_set_source_rgba (cr, 0., 0.5, 0., 1);
cairo_pw_d2_sb(cr, B);
cairo_stroke(cr);
Toy::draw(cr, notify, width, height, save,timer_stream);
}
public:
SBZeros () {
for(unsigned i = 0; i < SIZE; i++)
pB1.push_back(150+uniform()*300,150+uniform()*300);
for(unsigned i = 0; i < SIZE; i++)
pB2.push_back(150+uniform()*300,150+uniform()*300);
handles.push_back(&pB1);
handles.push_back(&pB2);
}
};
int main(int argc, char **argv) {
init(argc, argv, new SBZeros());
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=4:softtabstop=4:fileencoding=utf-8:textwidth=99 :
|
