update to trunk

(bzr r12588.1.45)

1 files changed, 111 insertions, 46 deletions

diff --git a/src/2geom/curve.cpp b/src/2geom/curve.cpp
index c0f2bf883..b45228514 100644
--- a/src/2geom/curve.cpp
+++ b/src/2geom/curve.cpp
@@ -32,62 +32,26 @@
  */
 
 #include <2geom/curve.h>
-#include <2geom/nearest-point.h>
+#include <2geom/exception.h>
+#include <2geom/nearest-time.h>
 #include <2geom/sbasis-geometric.h>
+#include <2geom/sbasis-to-bezier.h>
 #include <2geom/ord.h>
+#include <2geom/path-sink.h>
+
+//#include <iostream>
 
 namespace Geom 
 {
 
-int CurveHelpers::root_winding(Curve const &c, Point p) {
-    std::vector<double> ts = c.roots(p[Y], Y);
-
-    if(ts.empty()) return 0;
-
-    double const fudge = 0.01; //fudge factor used on first and last
-
-    std::sort(ts.begin(), ts.end());
-
-    // winding determined by crossings at roots
-    int wind=0;
-    // previous time
-    double pt = ts.front() - fudge;
-    for ( std::vector<double>::iterator ti = ts.begin()
-        ; ti != ts.end()
-        ; ++ti )
-    {
-        double t = *ti;
-        if ( t <= 0. || t >= 1. ) continue; //skip endpoint roots 
-        if ( c.valueAt(t, X) > p[X] ) { // root is ray intersection
-            // Get t of next:
-            std::vector<double>::iterator next = ti;
-            ++next;
-            double nt;
-            if(next == ts.end()) nt = t + fudge; else nt = *next;
-            
-            // Check before in time and after in time for positions
-            // Currently we're using the average times between next and previous segs
-            Cmp after_to_ray =  cmp(c.valueAt((t + nt) / 2, Y), p[Y]);
-            Cmp before_to_ray = cmp(c.valueAt((t + pt) / 2, Y), p[Y]);
-            // if y is included, these will have opposite values, giving order.
-            Cmp dt = cmp(after_to_ray, before_to_ray);
-            if(dt != EQUAL_TO) //Should always be true, but yah never know..
-                wind += dt;
-            pt = t;
-        }
-    }
-    
-    return wind;
-}
-
-Coord Curve::nearestPoint(Point const& p, Coord a, Coord b) const
+Coord Curve::nearestTime(Point const& p, Coord a, Coord b) const
 {
-    return nearest_point(p, toSBasis(), a, b);
+    return nearest_time(p, toSBasis(), a, b);
 }
 
-std::vector<Coord> Curve::allNearestPoints(Point const& p, Coord from, Coord to) const
+std::vector<Coord> Curve::allNearestTimes(Point const& p, Coord from, Coord to) const
 {
-    return all_nearest_points(p, toSBasis(), from, to);
+    return all_nearest_times(p, toSBasis(), from, to);
 }
 
 Coord Curve::length(Coord tolerance) const
@@ -95,6 +59,97 @@ Coord Curve::length(Coord tolerance) const
     return ::Geom::length(toSBasis(), tolerance);
 }
 
+int Curve::winding(Point const &p) const
+{
+    try {
+        std::vector<Coord> ts = roots(p[Y], Y);
+        if(ts.empty()) return 0;
+        std::sort(ts.begin(), ts.end());
+
+        // skip endpoint roots when they are local maxima on the Y axis
+        // this follows the convention used in other winding routines,
+        // i.e. that the bottommost coordinate is not part of the shape
+        bool ingore_0 = unitTangentAt(0)[Y] <= 0;
+        bool ignore_1 = unitTangentAt(1)[Y] >= 0;
+
+        int wind = 0;
+        for (std::size_t i = 0; i < ts.size(); ++i) {
+            Coord t = ts[i];
+            //std::cout << t << std::endl;
+            if ((t == 0 && ingore_0) || (t == 1 && ignore_1)) continue;
+            if (valueAt(t, X) > p[X]) { // root is ray intersection
+                Point tangent = unitTangentAt(t);
+                if (tangent[Y] > 0) {
+                    // at the point of intersection, curve goes in +Y direction,
+                    // so it winds in the direction of positive angles
+                    ++wind;
+                } else if (tangent[Y] < 0) {
+                    --wind;
+                }
+            }
+        }
+        return wind;
+    } catch (InfiniteSolutions const &e) {
+        // this means we encountered a line segment exactly coincident with the point
+        // skip, since this will be taken care of by endpoint roots in other segments
+        return 0;
+    }
+}
+
+std::vector<CurveIntersection> Curve::intersect(Curve const &/*other*/, Coord /*eps*/) const
+{
+    // TODO: approximate as Bezier
+    THROW_NOTIMPLEMENTED();
+}
+
+std::vector<CurveIntersection> Curve::intersectSelf(Coord eps) const
+{
+    std::vector<CurveIntersection> result;
+    // Monotonic segments cannot have self-intersections.
+    // Thus, we can split the curve at roots and intersect the portions.
+    std::vector<Coord> splits;
+    std::auto_ptr<Curve> deriv(derivative());
+    splits = deriv->roots(0, X);
+    if (splits.empty()) {
+        return result;
+    }
+    deriv.reset();
+    splits.push_back(1.);
+
+    boost::ptr_vector<Curve> parts;
+    Coord previous = 0;
+    for (unsigned i = 0; i < splits.size(); ++i) {
+        if (splits[i] == 0.) continue;
+        parts.push_back(portion(previous, splits[i]));
+        previous = splits[i];
+    }
+
+    Coord prev_i = 0;
+    for (unsigned i = 0; i < parts.size()-1; ++i) {
+        Interval dom_i(prev_i, splits[i]);
+        prev_i = splits[i];
+
+        Coord prev_j = 0;
+        for (unsigned j = i+1; j < parts.size(); ++j) {
+            Interval dom_j(prev_j, splits[j]);
+            prev_j = splits[j];
+
+            std::vector<CurveIntersection> xs = parts[i].intersect(parts[j], eps);
+            for (unsigned k = 0; k < xs.size(); ++k) {
+                // to avoid duplicated intersections, skip values at exactly 1
+                if (xs[k].first == 1. || xs[k].second == 1.) continue;
+
+                Coord ti = dom_i.valueAt(xs[k].first);
+                Coord tj = dom_j.valueAt(xs[k].second);
+
+                CurveIntersection real(ti, tj, xs[k].point());
+                result.push_back(real);
+            }
+        }
+    }
+    return result;
+}
+
 Point Curve::unitTangentAt(Coord t, unsigned n) const
 {
     std::vector<Point> derivs = pointAndDerivatives(t, n);
@@ -108,6 +163,16 @@ Point Curve::unitTangentAt(Coord t, unsigned n) const
     return Point (0,0);
 };
 
+void Curve::feed(PathSink &sink, bool moveto_initial) const
+{
+    std::vector<Point> pts;
+    sbasis_to_bezier(pts, toSBasis(), 2); //TODO: use something better!
+    if (moveto_initial) {
+        sink.moveTo(initialPoint());
+    }
+    sink.curveTo(pts[0], pts[1], pts[2]);
+}
+
 } // namespace Geom
 
 /*