1 files changed, 113 insertions, 0 deletions
diff --git a/src/toys/center-warp.cpp b/src/toys/center-warp.cpp
new file mode 100644
index 0000000..4c0f750
--- /dev/null
+++ b/src/toys/center-warp.cpp
@@ -0,0 +1,113 @@
+#include <2geom/bezier-to-sbasis.h>
+#include <2geom/d2.h>
+#include <2geom/path.h>
+#include <2geom/sbasis-2d.h>
+#include <2geom/sbasis-geometric.h>
+#include <2geom/sbasis.h>
+#include <2geom/sbasis-math.h>
+#include <2geom/svg-path-parser.h>
+#include <2geom/transforms.h>
+
+#include <toys/path-cairo.h>
+#include <toys/toy-framework-2.h>
+
+#include <vector>
+using std::vector;
+using namespace Geom;
+
+unsigned total_pieces_sub;
+unsigned total_pieces_inc;
+
+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);
+    }
+}
+
+class CentreWarp: public Toy {
+    Path path_a;
+    D2<SBasis2d> sb2;
+    Piecewise<D2<SBasis> >  path_a_pw;
+    PointHandle brush_handle;
+    void draw(cairo_t *cr, std::ostringstream *notify, int width, int height, bool save, std::ostringstream *timer_stream) override {
+        Geom::Point dir(1,-2);
+
+	D2<Piecewise<SBasis> > B = make_cuts_independent(path_a_pw);
+
+	cairo_set_source_rgba (cr, 0., 0.125, 0, 1);
+
+        if(0) {
+            D2<Piecewise<SBasis> > tB(cos(B[0]*0.1)*(brush_handle.pos[0]/100) + B[0], 
+                                      cos(B[1]*0.1)*(brush_handle.pos[1]/100) + B[1]);
+	
+            cairo_d2_pw_sb(cr, tB);
+        } else  {
+            Piecewise<SBasis> r2 = (dot(path_a_pw - brush_handle.pos, path_a_pw - brush_handle.pos));
+            Piecewise<SBasis> rc;
+            rc.push_cut(0);
+            rc.push(SBasis(Linear(1, 1)), 2);
+            rc.push(SBasis(Linear(1, 0)), 4);
+            rc.push(SBasis(Linear(0, 0)), 30);
+            rc *= 10;
+            rc.scaleDomain(1000);
+            Piecewise<SBasis> swr;
+            swr.push_cut(0);
+            swr.push(SBasis(Linear(0, 1)), 2);
+            swr.push(SBasis(Linear(1, 0)), 4);
+            swr.push(SBasis(Linear(0, 0)), 30);
+            swr *= 10;
+            swr.scaleDomain(1000);
+            cairo_pw(cr, swr);// + (height - 100));
+            D2<Piecewise<SBasis> >  uB = make_cuts_independent(unitVector(path_a_pw - brush_handle.pos));
+        
+            D2<Piecewise<SBasis> > tB(compose(rc, (r2))*uB[0] + B[0], 
+                                      compose(rc, (r2))*uB[1] + B[1]);
+            cairo_d2_pw_sb(cr, tB);
+            //path_a_pw = sectionize(tB);
+	}
+	cairo_stroke(cr);
+        
+        *notify << path_a_pw.size();
+        
+        Toy::draw(cr, notify, width, height, save,timer_stream);
+    }
+    void first_time(int argc, char** argv) override {
+        const char *path_a_name="star.svgd";
+        if(argc > 1)
+            path_a_name = argv[1];
+        PathVector paths_a = read_svgd(path_a_name);
+        assert(!paths_a.empty());
+        path_a = paths_a[0];
+        
+	path_a.close(true);
+        path_a_pw = path_a.toPwSb();
+        for(unsigned dim = 0; dim < 2; dim++) {
+            sb2[dim].us = 2;
+            sb2[dim].vs = 2;
+            const int depth = sb2[dim].us*sb2[dim].vs;
+            sb2[dim].resize(depth, Linear2d(0));
+        }
+        
+        handles.push_back(&brush_handle);
+        brush_handle.pos = Point(100,100);
+    }
+};
+
+int main(int argc, char **argv) {
+    init(argc, argv, new CentreWarp);
+    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 :