1 files changed, 100 insertions, 0 deletions
diff --git a/src/toys/pw-funcs.cpp b/src/toys/pw-funcs.cpp
new file mode 100644
index 0000000..f4c6471
--- /dev/null
+++ b/src/toys/pw-funcs.cpp
@@ -0,0 +1,100 @@
+#include <2geom/piecewise.h>
+#include <2geom/sbasis.h>
+#include <2geom/sbasis-math.h>
+#include <2geom/bezier-to-sbasis.h>
+
+#include <toys/path-cairo.h>
+#include <toys/toy-framework-2.h>
+
+#include <vector>
+
+using namespace Geom;
+using namespace std;
+
+void cairo_pw(cairo_t *cr, Piecewise<SBasis> p) {
+    for(unsigned i = 0; i < p.size(); i++) {
+        D2<SBasis> B;
+        B[0] = Linear(p.cuts[i], p.cuts[i+1]);
+        B[1] = p[i];
+        cairo_d2_sb(cr, B);
+    }
+}
+
+void cairo_horiz(cairo_t *cr, double y, vector<double> p) {
+    for(double i : p) {
+        cairo_move_to(cr, i, y);
+        cairo_rel_line_to(cr, 0, 10);
+    }
+}
+
+void cairo_vert(cairo_t *cr, double x, vector<double> p) {
+    for(double i : p) {
+        cairo_move_to(cr, x, i);
+        cairo_rel_line_to(cr, 10, 0);
+    }
+}
+
+Piecewise<SBasis> log(Interval in) {
+    Piecewise<SBasis> I = integral(Geom::reciprocal(Linear(in.min(), in.max())));
+    return I + Piecewise<SBasis> (-I.segs[0][0] + log(in.min()));
+}
+
+Piecewise<SBasis> xlogx(Interval in) {
+    Piecewise<SBasis> I = integral(log(in) + Piecewise<SBasis>(1));
+    return I + Piecewise<SBasis> (-I.segs[0][0] + in.min()*log(in.min()));
+}
+
+class PwToy: public Toy {
+    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., 0., 1);
+        cairo_set_line_width (cr, 1);
+        
+        Piecewise<SBasis> pws;
+        
+        //pws = Geom::cos(Linear(0,100)) + 3;
+        pws = Geom::sqrt(Linear(0,100));
+        //pws = log(Interval(1,8));
+        //Piecewise<SBasis> l(Linear(-100,100));
+        //Piecewise<SBasis> one(Linear(1,1));
+        //pws = Geom::reciprocal(l*l + one)*l + l;
+        //pws = xlogx(Interval(0.5,3));
+        //pws = Geom::reciprocal(pws);
+        //pws = -integral(Geom::reciprocal(Linear(1,2)))*Piecewise<SBasis>(Linear(1,2));
+        
+        pws = -pws*width/4 + width/2;
+        pws.scaleDomain(width/2);
+        pws.offsetDomain(width/4);
+
+        cairo_pw(cr, pws);
+
+        cairo_stroke(cr);
+        cairo_set_source_rgba (cr, 0., 0., .5, 1.);
+        cairo_horiz(cr, 500, pws.cuts);
+        cairo_stroke(cr);
+
+        *notify << "total pieces: " << pws.size();
+
+        Toy::draw(cr, notify, width, height, save,timer_stream);
+    }
+
+    bool should_draw_numbers() override { return false; }
+    int should_draw_bounds() override { return 2; }
+    public:
+    PwToy () {}
+};
+
+int main(int argc, char **argv) {
+    init(argc, argv, new PwToy());
+    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 :