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#include <2geom/sbasis.h>
#include <2geom/bezier-to-sbasis.h>
#include <2geom/solver.h>
#include <2geom/sbasis-poly.h>
#include "../2geom/orphan-code/nearestpoint.cpp" // FIXME: This looks like it may give problems later, (including a .cpp file)
#include <2geom/path.h>
#include <toys/path-cairo.h>
#include <toys/toy-framework-2.h>
#define ZROOTS_TEST 0
#if ZROOTS_TEST
#include <2geom/zroots.c>
#endif
using std::swap;
namespace Geom{
extern void subdiv_sbasis(SBasis const & s,
std::vector<double> & roots,
double left, double right);
};
double eval_bernstein(double* w, double t, unsigned N) {
double Vtemp[2*N];
//const int degree = N-1;
for (unsigned i = 0; i < N; i++)
Vtemp[i] = w[i];
/* Triangle computation */
const double omt = (1-t);
//Left[0] = Vtemp[0];
//Right[degree] = Vtemp[degree];
double *prev_row = Vtemp;
double *row = Vtemp + N;
for (unsigned i = 1; i < N; i++) {
for (unsigned j = 0; j < N - i; j++) {
row[j] = omt*prev_row[j] + t*prev_row[j+1];
}
//Left[i] = row[0];
//Right[degree-i] = row[degree-i];
swap(prev_row, row);
}
return prev_row[0];
}
#include <vector>
using std::vector;
using namespace Geom;
#ifdef HAVE_GSL
#include <complex>
using std::complex;
#endif
class RootFinderComparer: public Toy {
public:
PointSetHandle psh;
void draw(cairo_t *cr, std::ostringstream *notify, int width, int height, bool save, std::ostringstream *timer_stream) override {
std::vector<Geom::Point> trans;
trans.resize(psh.size());
for(unsigned i = 0; i < handles.size(); i++) {
trans[i] = psh.pts[i] - Geom::Point(0, height/2);
}
Timer tm;
std::vector<double> solutions;
solutions.resize(6);
tm.ask_for_timeslice();
tm.start();
FindRoots(&trans[0], 5, &solutions[0], 0);
Timer::Time als_time = tm.lap();
*notify << "original time = " << als_time << std::endl;
D2<SBasis> test_sb = psh.asBezier();//handles_to_sbasis(handles.begin(),5);
Interval bs = *bounds_exact(test_sb[1]);
cairo_move_to(cr, test_sb[0](0), bs.min());
cairo_line_to(cr, test_sb[0](1), bs.min());
cairo_move_to(cr, test_sb[0](0), bs.max());
cairo_line_to(cr, test_sb[0](1), bs.max());
cairo_stroke(cr);
*notify << "sb bounds = "<<bs.min()<< ", " <<bs.max()<<std::endl;
Poly ply = sbasis_to_poly(test_sb[1]);
ply = Poly(height/2) - ply;
cairo_move_to(cr, 0, height/2);
cairo_line_to(cr, width, height/2);
cairo_stroke(cr);
#ifdef HAVE_GSL
vector<complex<double> > complex_solutions;
complex_solutions = solve(ply);
#if 1
*notify << "gsl: ";
std::copy(complex_solutions.begin(), complex_solutions.end(), std::ostream_iterator<std::complex<double> >(*notify, ",\t"));
*notify << std::endl;
#endif
#endif
#if ZROOTS_TEST
fcomplex a[ply.size()];
for(unsigned i = 0; i < ply.size(); i++) {
a[i] = ply[i];
}
//copy(a, a+ply.size(), ply.begin());
fcomplex rts[ply.size()];
zroots(a, ply.size(), rts, true);
for(unsigned i = 0; i < ply.size(); i++) {
if(! a[i].imag())
solutions[i] = a[i].real();
}
#endif
#ifdef HAVE_GSL
tm.ask_for_timeslice();
tm.start();
solve(ply);
als_time = tm.lap();
*timer_stream << "gsl poly = " << als_time << std::endl;
#endif
#if ZROOTS_TEST
tm.ask_for_timeslice();
tm.start();
zroots(a, ply.size(), rts, false);
als_time = tm.lap();
*timer_stream << "zroots poly = " << als_time << std::endl;
#endif
#if LAGUERRE_TEST
tm.ask_for_timeslice();
tm.start();
Laguerre(ply);
als_time = tm.lap();
*timer_stream << "Laguerre poly = " << als_time << std::endl;
complex_solutions = Laguerre(ply);
#endif
#define SBASIS_SUBDIV_TEST 0
#if SBASIS_SUBDIV_TEST
tm.ask_for_timeslice();
tm.start();
subdiv_sbasis(-test_sb[1] + Linear(3*width/4),
rts, 0, 1);
als_time = tm.lap();
*timer_stream << "sbasis subdivision = " << als_time << std::endl;
#endif
#if 0
tm.ask_for_timeslice();
tm.start();
solutions.resize(0);
find_parametric_bezier_roots(&trans[0], 5, solutions, 0);
als_time = tm.lap();
*timer_stream << "solver parametric = " << als_time << std::endl;
#endif
double ys[trans.size()];
for(unsigned i = 0; i < trans.size(); i++) {
ys[i] = trans[i][1];
double x = double(i)/(trans.size()-1);
x = (1-x)*height/4 + x*height*3/4;
draw_handle(cr, Geom::Point(x, height/2 + ys[i]));
}
solutions.resize(0);
tm.ask_for_timeslice();
tm.start();
find_bernstein_roots(ys, 5, solutions, 0, 0, 1, false);
als_time = tm.lap();
*notify << "found sub solutions at:\n";
std::copy(solutions.begin(), solutions.end(), std::ostream_iterator<double >(*notify, ","));
*notify << "solver 1d bernstein subdivision n_slns = " << solutions.size()
<< ", time = " << als_time << std::endl;
solutions.resize(0);
tm.ask_for_timeslice();
tm.start();
find_bernstein_roots(ys, 5, solutions, 0, 0, 1, true);
als_time = tm.lap();
*notify << "solver 1d bernstein secant subdivision slns" << solutions.size()
<< ", time = " << als_time << std::endl;
*notify << "found secant solutions at:\n";
std::copy(solutions.begin(), solutions.end(), std::ostream_iterator<double >(*notify, ","));
*notify << "solver 1d bernstein subdivision accuracy:"
<< std::endl;
for(double solution : solutions) {
*notify << solution << ":" << eval_bernstein(ys, solution, trans.size()) << ",";
}
tm.ask_for_timeslice();
tm.start();
solutions = roots( -test_sb[1] + Linear(height/2));
als_time = tm.lap();
#if 1
*notify << "sbasis roots: ";
std::copy(solutions.begin(), solutions.end(), std::ostream_iterator<double>(*notify, ",\t"));
*notify << "\n time = " << als_time << std::endl;
#endif
for(double solution : solutions) {
double x = test_sb[0](solution);
draw_cross(cr, Geom::Point(x, height/2));
}
*notify << "found " << solutions.size() << "solutions at:\n";
std::copy(solutions.begin(), solutions.end(), std::ostream_iterator<double >(*notify, ","));
D2<SBasis> B = psh.asBezier();//handles_to_sbasis(handles.begin(), 5);
Geom::Path pb;
pb.append(B);
pb.close(false);
cairo_path(cr, pb);
B[0] = Linear(width/4, 3*width/4);
cairo_d2_sb(cr, B);
Toy::draw(cr, notify, width, height, save,timer_stream);
}
RootFinderComparer(unsigned degree)
{
for(unsigned i = 0; i < degree; i++) psh.push_back(Geom::Point(uniform()*400, uniform()*400));
handles.push_back(&psh);
}
};
int main(int argc, char **argv) {
unsigned bez_ord = 6;
if(argc > 1)
sscanf(argv[1], "%d", &bez_ord);
init(argc, argv, new RootFinderComparer(bez_ord));
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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