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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;
//-----------------------------------------------
class CurvatureTester: public Toy {
PointSetHandle curve_handle;
Path current_curve;
void draw(cairo_t *cr, std::ostringstream *notify, int width, int height, bool save, std::ostringstream *timer_stream) override {
cairo_set_line_width (cr, 1);
current_curve = Path();
for(int base_i = 0; base_i < int(curve_handle.pts.size()/2) - 1; base_i++) {
for(int i = 0; i < 2; i++) {
Geom::Point center=curve_handle.pts[1+2*i+base_i*2];
Geom::Point normal=center- curve_handle.pts[2*i+base_i*2];
double radius = Geom::L2(normal);
*notify<<"K="<<radius<<std::endl;
if (fabs(radius)>1e-4){
double ang = atan2(-normal);
cairo_arc(cr, center[0], center[1],fabs(radius), ang-0.3, ang+0.3);
cairo_set_source_rgba (cr, 0.75, 0.89, 1., 1);
cairo_stroke(cr);
//draw_handle(cr, center);
}else{
}
{
cairo_save(cr);
double dashes[2] = {10, 10};
cairo_set_dash(cr, dashes, 2, 0);
cairo_move_to(cr, center);
cairo_line_to(cr, center-normal);
cairo_stroke(cr);
cairo_restore(cr);
}
}
cairo_set_source_rgba (cr, 0., 0, 0., 1);
Geom::Point A = curve_handle.pts[0+base_i*2];
Geom::Point B = curve_handle.pts[2+base_i*2];
D2<SBasis> best_c = D2<SBasis>(SBasis(Linear(A[X],B[X])),SBasis(Linear(A[Y],B[Y])));
double error = -1;
for(int i = 0; i < 16; i++) {
Geom::Point dA = curve_handle.pts[1+base_i*2]-A;
Geom::Point dB = curve_handle.pts[3+base_i*2]-B;
std::vector<D2<SBasis> > candidates =
cubics_fitting_curvature(curve_handle.pts[0+base_i*2],curve_handle.pts[2+base_i*2],
(i&2)?rot90(dA):-rot90(dA),
(i&1)?rot90(dB):-rot90(dB),
((i&4)?-1:1)*L2sq(dA), ((i&8)?-1:1)*L2sq(dB));
if (candidates.empty()) {
} else {
//TODO: I'm sure std algorithm could do that for me...
unsigned best = 0;
for (unsigned i=0; i<candidates.size(); i++){
Piecewise<SBasis> K = arcLengthSb(candidates[i]);
double l = Geom::length(candidates[i]);
//double l = K.segs.back().at1();//Geom::length(candidates[i]);
//printf("l = %g\n", l);
if ( l < error || error < 0 ){
error = l;
best = i;
best_c = candidates[best];
}
}
}
}
if(error >= 0) {
//cairo_d2_sb(cr, best_c);
current_curve.append(best_c);
}
}
cairo_path(cr, current_curve);
cairo_stroke(cr);
Toy::draw(cr, notify, width, height, save,timer_stream);
}
void canvas_click(Geom::Point at, int button) override {
std::cout << "clicked at:" << at << " with button " << button << std::endl;
if(button == 1) {
double dist;
double t = current_curve.nearestTime(at, &dist).asFlatTime();
if(dist > 5) {
curve_handle.push_back(at);
curve_handle.push_back(at+Point(100,100));
} else {
// split around t
Piecewise<D2<SBasis> > pw = current_curve.toPwSb();
std::vector<Point > vnd = pw.valueAndDerivatives(t, 2);
Point on_curve = current_curve(t);
Point normal = rot90(vnd[1]);
Piecewise<SBasis > K = curvature(pw);
Point ps[2] = {on_curve, on_curve+unit_vector(normal)/K(t)};
curve_handle.pts.insert(curve_handle.pts.begin()+2*(int(t)+1), ps, ps+2);
}
}
}
public:
CurvatureTester(){
if(handles.empty()) {
handles.push_back(&curve_handle);
for(unsigned i = 0; i < 4; i++)
curve_handle.push_back(150+uniform()*300,150+uniform()*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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