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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/choose.h>
#include <2geom/convex-hull.h>
#include <2geom/path.h>
#include <toys/path-cairo.h>
#include <toys/toy-framework-2.h>
#include <vector>
using std::vector;
using namespace Geom;
extern unsigned total_steps, total_subs;
double& handle_to_sb(unsigned i, unsigned n, SBasis &sb) {
assert(i < n);
assert(n <= sb.size()*2);
unsigned k = i;
if(k >= n/2) {
k = n - k - 1;
return sb[k][1];
} else
return sb[k][0];
}
double handle_to_sb_t(unsigned i, unsigned n) {
double k = i;
if(i >= n/2)
k = n - k - 1;
double t = k/(2*k+1);
if(i >= n/2)
return 1 - t;
else
return t;
}
class Sb1d: public Toy {
public:
PointSetHandle hand;
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., 0.5, 0, 1);
cairo_set_line_width (cr, 1);
if(!save) {
for(unsigned i = 0; i < hand.pts.size(); i++) {
hand.pts[i][0] = width*handle_to_sb_t(i, hand.pts.size())/2 + width/4;
if(i)
cairo_line_to(cr, hand.pts[i]);
else
cairo_move_to(cr, hand.pts[i]);
}
}
D2<SBasis> B;
B[0] = Linear(width/4, 3*width/4);
B[1].resize(hand.pts.size()/2);
for(auto & i : B) {
i = Linear(0);
}
for(unsigned i = 0; i < hand.pts.size(); i++) {
handle_to_sb(i, hand.pts.size(), B[1]) = 3*width/4 - hand.pts[i][1];
}
for(unsigned i = 1; i < B[1].size(); i++) {
B[1][i] = B[1][i]*choose<double>(2*i+1, i);
}
Interval bs = *bounds_fast(B[1]);
double lo, hi;
lo = 3*width/4 - bs.min();
hi = 3*width/4 - bs.max();
cairo_move_to(cr, B[0](0), lo);
cairo_line_to(cr, B[0](1), lo);
cairo_move_to(cr, B[0](0), hi);
cairo_line_to(cr, B[0](1), hi);
cairo_stroke(cr);
*notify << "sb bounds = "<<lo << ", " <<hi<<std::endl;
//B[1] = SBasis(Linear(3*width/4)) - B[1];
*notify << B[0] << ", ";
*notify << B[1];
Geom::Path pb;
B[1] = SBasis(Linear(3*width/4)) - B[1];
pb.append(B);
pb.close(false);
cairo_path(cr, pb);
cairo_set_source_rgba (cr, 0., 0.125, 0, 1);
cairo_stroke(cr);
Geom::ConvexHull ch(hand.pts);
cairo_move_to(cr, ch.back());
for(auto i : ch) {
cairo_line_to(cr, i);
}
Toy::draw(cr, notify, width, height, save,timer_stream);
}
public:
Sb1d () {
hand.pts.emplace_back(0,450);
for(unsigned i = 0; i < 4; i++)
hand.pts.emplace_back(uniform()*400, uniform()*400);
hand.pts.emplace_back(0,450);
handles.push_back(&hand);
}
};
int main(int argc, char **argv) {
init(argc, argv, new Sb1d());
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 :
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