1 files changed, 110 insertions, 0 deletions
diff --git a/src/3rdparty/2geom/src/toys/curvature-test.cpp b/src/3rdparty/2geom/src/toys/curvature-test.cpp
new file mode 100644
index 0000000..c209fe3
--- /dev/null
+++ b/src/3rdparty/2geom/src/toys/curvature-test.cpp
@@ -0,0 +1,110 @@
+#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;
+
+// TODO: 
+// use path2
+// replace Ray stuff with path2 line segments.
+
+//-----------------------------------------------
+
+class CurvatureTester: public Toy {
+    PointSetHandle curve_handle;
+    PointHandle sample_point;
+    void draw(cairo_t *cr, std::ostringstream *notify, int width, int height, bool save, std::ostringstream *timer_stream) override {
+    
+        D2<SBasis> B = curve_handle.asBezier();
+
+        cairo_set_line_width (cr, 1);
+        cairo_set_source_rgba (cr, 0., 0.5, 0., 1);
+        cairo_d2_sb(cr, B);
+        cairo_stroke(cr);
+
+	sample_point.pos[1]=400;
+	sample_point.pos[0]=std::max(150.,sample_point.pos[0]);
+	sample_point.pos[0]=std::min(450.,sample_point.pos[0]);
+	cairo_move_to(cr, Geom::Point(150,400));
+	cairo_line_to(cr, Geom::Point(450,400));
+	cairo_set_source_rgba (cr, 0., 0., 0.5, 0.8);
+	cairo_stroke(cr);
+
+	double t=std::max(0.,std::min(1.,(sample_point.pos[0]-150)/300.));
+        Timer tm;
+        tm.ask_for_timeslice();
+        tm.start();
+        
+        Piecewise<SBasis> K = curvature(B);
+        Timer::Time als_time = tm.lap();
+        *timer_stream << "curvature " << als_time << std::endl;
+        
+        for(unsigned ix = 0; ix < K.segs.size(); ix++) {
+            D2<SBasis> Kxy;
+            Kxy[1] = Linear(400) - K.segs[ix]*300;
+            Kxy[0] = Linear(300*K.cuts[ix] + 150, 300*K.cuts[ix+1] + 150);
+            cairo_d2_sb(cr, Kxy);
+            cairo_stroke(cr);
+        }
+        
+	double radius = K(t);
+	*notify<<"K="<<radius<<std::endl;
+	if (fabs(radius)>1e-4){
+	  radius=1./radius;
+	  Geom::Point normal=unit_vector(derivative(B)(t));
+	  normal=rot90(normal);
+	  Geom::Point center=B(t)-radius*normal;
+	  
+	  cairo_arc(cr, center[0], center[1],fabs(radius), 0, M_PI*2);
+	  draw_handle(cr, center);
+	  draw_handle(cr, B(t));
+	}else{
+	  Geom::Point p=B(t);
+	  Geom::Point v=derivative(B)(t);
+	  draw_handle(cr, p);
+	  cairo_move_to(cr, p-100*v);
+	  cairo_line_to(cr, p+100*v);
+	}
+	cairo_set_source_rgba (cr, 0.5, 0.2, 0., 0.8);
+	cairo_stroke(cr);
+        Toy::draw(cr, notify, width, height, save,timer_stream);
+    }        
+  
+public:
+    CurvatureTester(){
+        if(handles.empty()) {
+            handles.push_back(&curve_handle);
+            handles.push_back(&sample_point);
+            for(unsigned i = 0; i < 4; i++)
+                curve_handle.push_back(150+uniform()*300,150+uniform()*300);
+            sample_point.pos = Geom::Point(250,300);
+        }
+    }
+};
+
+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 :
+
+