1 files changed, 83 insertions, 0 deletions
diff --git a/src/toys/sb2d.cpp b/src/toys/sb2d.cpp
new file mode 100644
index 0000000..b449d01
--- /dev/null
+++ b/src/toys/sb2d.cpp
@@ -0,0 +1,83 @@
+#include <2geom/sbasis.h>
+#include <2geom/sbasis-2d.h>
+#include <2geom/bezier-to-sbasis.h>
+
+#include <toys/path-cairo.h>
+#include <toys/toy-framework-2.h>
+
+using std::vector;
+using namespace Geom;
+
+unsigned total_pieces_sub;
+unsigned total_pieces_inc;
+
+class Sb2d: public Toy {
+public:
+    PointSetHandle hand;
+    Sb2d() {
+        handles.push_back(&hand);
+    }
+    void draw(cairo_t *cr, std::ostringstream *notify, int width, int height, bool save, std::ostringstream *timer_stream) override {
+        SBasis2d sb2;
+        sb2.us = 2;
+        sb2.vs = 2;
+        const int depth = sb2.us*sb2.vs;
+        const int surface_handles = 4*depth;
+        sb2.resize(depth, Linear2d(0));
+        vector<Geom::Point> display_handles(surface_handles);
+        Geom::Point dir(1,-2);
+        if(hand.pts.empty()) {
+            for(unsigned vi = 0; vi < sb2.vs; vi++)
+             for(unsigned ui = 0; ui < sb2.us; ui++)
+              for(unsigned iv = 0; iv < 2; iv++)
+               for(unsigned iu = 0; iu < 2; iu++)
+                   hand.pts.emplace_back((2*(iu+ui)/(2.*ui+1)+1)*width/4.,
+                                                 (2*(iv+vi)/(2.*vi+1)+1)*width/4.);
+        
+            hand.pts.push_back(Geom::Point(3*width/4., width/4.) + 30*dir);
+        }
+        dir = (hand.pts[surface_handles] - Geom::Point(3*width/4., width/4.)) / 30;
+        if(!save) {
+            cairo_move_to(cr, 3*width/4., width/4.);
+            cairo_line_to(cr, hand.pts[surface_handles]);
+        }
+        for(unsigned vi = 0; vi < sb2.vs; vi++)
+         for(unsigned ui = 0; ui < sb2.us; ui++)
+          for(unsigned iv = 0; iv < 2; iv++)
+           for(unsigned iu = 0; iu < 2; iu++) {
+               unsigned corner = iu + 2*iv;
+               unsigned i = ui + vi*sb2.us;
+               Geom::Point base((2*(iu+ui)/(2.*ui+1)+1)*width/4.,
+               (2*(iv+vi)/(2.*vi+1)+1)*width/4.);
+               double dl = dot((hand.pts[corner+4*i] - base), dir)/dot(dir,dir);
+               display_handles[corner+4*i] = dl*dir + base;
+               sb2[i][corner] = dl*10/(width/2)*pow(4.,(double)ui+vi);
+           }
+        cairo_sb2d(cr, sb2, dir*0.1, width);
+    
+        *notify << "bo = " << sb2.index(0,0); 
+    
+        cairo_set_source_rgba (cr, 0., 0.125, 0, 1);
+        cairo_stroke(cr);
+        if(!save)
+            for(auto & display_handle : display_handles)
+                draw_circ(cr, display_handle);
+        Toy::draw(cr, notify, width, height, save,timer_stream);
+    }
+};
+
+int main(int argc, char **argv) {
+        init(argc, argv, new Sb2d());
+        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 :