diff -r efd9c589177a -r c0b4a8b5a012 toolkit/javascript/d3/src/svg/line.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/toolkit/javascript/d3/src/svg/line.js	Thu Apr 10 14:20:23 2014 +0200
@@ -0,0 +1,415 @@
+function d3_svg_line(projection) {
+  var x = d3_svg_lineX,
+      y = d3_svg_lineY,
+      interpolate = "linear",
+      interpolator = d3_svg_lineInterpolators[interpolate],
+      tension = .7;
+
+  function line(d) {
+    return d.length < 1 ? null : "M" + interpolator(projection(d3_svg_linePoints(this, d, x, y)), tension);
+  }
+
+  line.x = function(v) {
+    if (!arguments.length) return x;
+    x = v;
+    return line;
+  };
+
+  line.y = function(v) {
+    if (!arguments.length) return y;
+    y = v;
+    return line;
+  };
+
+  line.interpolate = function(v) {
+    if (!arguments.length) return interpolate;
+    interpolator = d3_svg_lineInterpolators[interpolate = v];
+    return line;
+  };
+
+  line.tension = function(v) {
+    if (!arguments.length) return tension;
+    tension = v;
+    return line;
+  };
+
+  return line;
+}
+
+d3.svg.line = function() {
+  return d3_svg_line(Object);
+};
+
+// Converts the specified array of data into an array of points
+// (x-y tuples), by evaluating the specified `x` and `y` functions on each
+// data point. The `this` context of the evaluated functions is the specified
+// "self" object; each function is passed the current datum and index.
+function d3_svg_linePoints(self, d, x, y) {
+  var points = [],
+      i = -1,
+      n = d.length,
+      fx = typeof x === "function",
+      fy = typeof y === "function",
+      value;
+  if (fx && fy) {
+    while (++i < n) points.push([
+      x.call(self, value = d[i], i),
+      y.call(self, value, i)
+    ]);
+  } else if (fx) {
+    while (++i < n) points.push([x.call(self, d[i], i), y]);
+  } else if (fy) {
+    while (++i < n) points.push([x, y.call(self, d[i], i)]);
+  } else {
+    while (++i < n) points.push([x, y]);
+  }
+  return points;
+}
+
+// The default `x` property, which references d[0].
+function d3_svg_lineX(d) {
+  return d[0];
+}
+
+// The default `y` property, which references d[1].
+function d3_svg_lineY(d) {
+  return d[1];
+}
+
+// The various interpolators supported by the `line` class.
+var d3_svg_lineInterpolators = {
+  "linear": d3_svg_lineLinear,
+  "step-before": d3_svg_lineStepBefore,
+  "step-after": d3_svg_lineStepAfter,
+  "basis": d3_svg_lineBasis,
+  "basis-open": d3_svg_lineBasisOpen,
+  "basis-closed": d3_svg_lineBasisClosed,
+  "bundle": d3_svg_lineBundle,
+  "cardinal": d3_svg_lineCardinal,
+  "cardinal-open": d3_svg_lineCardinalOpen,
+  "cardinal-closed": d3_svg_lineCardinalClosed,
+  "monotone": d3_svg_lineMonotone
+};
+
+// Linear interpolation; generates "L" commands.
+function d3_svg_lineLinear(points) {
+  var i = 0,
+      n = points.length,
+      p = points[0],
+      path = [p[0], ",", p[1]];
+  while (++i < n) path.push("L", (p = points[i])[0], ",", p[1]);
+  return path.join("");
+}
+
+// Step interpolation; generates "H" and "V" commands.
+function d3_svg_lineStepBefore(points) {
+  var i = 0,
+      n = points.length,
+      p = points[0],
+      path = [p[0], ",", p[1]];
+  while (++i < n) path.push("V", (p = points[i])[1], "H", p[0]);
+  return path.join("");
+}
+
+// Step interpolation; generates "H" and "V" commands.
+function d3_svg_lineStepAfter(points) {
+  var i = 0,
+      n = points.length,
+      p = points[0],
+      path = [p[0], ",", p[1]];
+  while (++i < n) path.push("H", (p = points[i])[0], "V", p[1]);
+  return path.join("");
+}
+
+// Open cardinal spline interpolation; generates "C" commands.
+function d3_svg_lineCardinalOpen(points, tension) {
+  return points.length < 4
+      ? d3_svg_lineLinear(points)
+      : points[1] + d3_svg_lineHermite(points.slice(1, points.length - 1),
+        d3_svg_lineCardinalTangents(points, tension));
+}
+
+// Closed cardinal spline interpolation; generates "C" commands.
+function d3_svg_lineCardinalClosed(points, tension) {
+  return points.length < 3
+      ? d3_svg_lineLinear(points)
+      : points[0] + d3_svg_lineHermite((points.push(points[0]), points),
+        d3_svg_lineCardinalTangents([points[points.length - 2]]
+        .concat(points, [points[1]]), tension));
+}
+
+// Cardinal spline interpolation; generates "C" commands.
+function d3_svg_lineCardinal(points, tension, closed) {
+  return points.length < 3
+      ? d3_svg_lineLinear(points)
+      : points[0] + d3_svg_lineHermite(points,
+        d3_svg_lineCardinalTangents(points, tension));
+}
+
+// Hermite spline construction; generates "C" commands.
+function d3_svg_lineHermite(points, tangents) {
+  if (tangents.length < 1
+      || (points.length != tangents.length
+      && points.length != tangents.length + 2)) {
+    return d3_svg_lineLinear(points);
+  }
+
+  var quad = points.length != tangents.length,
+      path = "",
+      p0 = points[0],
+      p = points[1],
+      t0 = tangents[0],
+      t = t0,
+      pi = 1;
+
+  if (quad) {
+    path += "Q" + (p[0] - t0[0] * 2 / 3) + "," + (p[1] - t0[1] * 2 / 3)
+        + "," + p[0] + "," + p[1];
+    p0 = points[1];
+    pi = 2;
+  }
+
+  if (tangents.length > 1) {
+    t = tangents[1];
+    p = points[pi];
+    pi++;
+    path += "C" + (p0[0] + t0[0]) + "," + (p0[1] + t0[1])
+        + "," + (p[0] - t[0]) + "," + (p[1] - t[1])
+        + "," + p[0] + "," + p[1];
+    for (var i = 2; i < tangents.length; i++, pi++) {
+      p = points[pi];
+      t = tangents[i];
+      path += "S" + (p[0] - t[0]) + "," + (p[1] - t[1])
+          + "," + p[0] + "," + p[1];
+    }
+  }
+
+  if (quad) {
+    var lp = points[pi];
+    path += "Q" + (p[0] + t[0] * 2 / 3) + "," + (p[1] + t[1] * 2 / 3)
+        + "," + lp[0] + "," + lp[1];
+  }
+
+  return path;
+}
+
+// Generates tangents for a cardinal spline.
+function d3_svg_lineCardinalTangents(points, tension) {
+  var tangents = [],
+      a = (1 - tension) / 2,
+      p0,
+      p1 = points[0],
+      p2 = points[1],
+      i = 1,
+      n = points.length;
+  while (++i < n) {
+    p0 = p1;
+    p1 = p2;
+    p2 = points[i];
+    tangents.push([a * (p2[0] - p0[0]), a * (p2[1] - p0[1])]);
+  }
+  return tangents;
+}
+
+// B-spline interpolation; generates "C" commands.
+function d3_svg_lineBasis(points) {
+  if (points.length < 3) return d3_svg_lineLinear(points);
+  var i = 1,
+      n = points.length,
+      pi = points[0],
+      x0 = pi[0],
+      y0 = pi[1],
+      px = [x0, x0, x0, (pi = points[1])[0]],
+      py = [y0, y0, y0, pi[1]],
+      path = [x0, ",", y0];
+  d3_svg_lineBasisBezier(path, px, py);
+  while (++i < n) {
+    pi = points[i];
+    px.shift(); px.push(pi[0]);
+    py.shift(); py.push(pi[1]);
+    d3_svg_lineBasisBezier(path, px, py);
+  }
+  i = -1;
+  while (++i < 2) {
+    px.shift(); px.push(pi[0]);
+    py.shift(); py.push(pi[1]);
+    d3_svg_lineBasisBezier(path, px, py);
+  }
+  return path.join("");
+}
+
+// Open B-spline interpolation; generates "C" commands.
+function d3_svg_lineBasisOpen(points) {
+  if (points.length < 4) return d3_svg_lineLinear(points);
+  var path = [],
+      i = -1,
+      n = points.length,
+      pi,
+      px = [0],
+      py = [0];
+  while (++i < 3) {
+    pi = points[i];
+    px.push(pi[0]);
+    py.push(pi[1]);
+  }
+  path.push(d3_svg_lineDot4(d3_svg_lineBasisBezier3, px)
+    + "," + d3_svg_lineDot4(d3_svg_lineBasisBezier3, py));
+  --i; while (++i < n) {
+    pi = points[i];
+    px.shift(); px.push(pi[0]);
+    py.shift(); py.push(pi[1]);
+    d3_svg_lineBasisBezier(path, px, py);
+  }
+  return path.join("");
+}
+
+// Closed B-spline interpolation; generates "C" commands.
+function d3_svg_lineBasisClosed(points) {
+  var path,
+      i = -1,
+      n = points.length,
+      m = n + 4,
+      pi,
+      px = [],
+      py = [];
+  while (++i < 4) {
+    pi = points[i % n];
+    px.push(pi[0]);
+    py.push(pi[1]);
+  }
+  path = [
+    d3_svg_lineDot4(d3_svg_lineBasisBezier3, px), ",",
+    d3_svg_lineDot4(d3_svg_lineBasisBezier3, py)
+  ];
+  --i; while (++i < m) {
+    pi = points[i % n];
+    px.shift(); px.push(pi[0]);
+    py.shift(); py.push(pi[1]);
+    d3_svg_lineBasisBezier(path, px, py);
+  }
+  return path.join("");
+}
+
+function d3_svg_lineBundle(points, tension) {
+  var n = points.length - 1,
+      x0 = points[0][0],
+      y0 = points[0][1],
+      dx = points[n][0] - x0,
+      dy = points[n][1] - y0,
+      i = -1,
+      p,
+      t;
+  while (++i <= n) {
+    p = points[i];
+    t = i / n;
+    p[0] = tension * p[0] + (1 - tension) * (x0 + t * dx);
+    p[1] = tension * p[1] + (1 - tension) * (y0 + t * dy);
+  }
+  return d3_svg_lineBasis(points);
+}
+
+// Returns the dot product of the given four-element vectors.
+function d3_svg_lineDot4(a, b) {
+  return a[0] * b[0] + a[1] * b[1] + a[2] * b[2] + a[3] * b[3];
+}
+
+// Matrix to transform basis (b-spline) control points to bezier
+// control points. Derived from FvD 11.2.8.
+var d3_svg_lineBasisBezier1 = [0, 2/3, 1/3, 0],
+    d3_svg_lineBasisBezier2 = [0, 1/3, 2/3, 0],
+    d3_svg_lineBasisBezier3 = [0, 1/6, 2/3, 1/6];
+
+// Pushes a "C" Bézier curve onto the specified path array, given the
+// two specified four-element arrays which define the control points.
+function d3_svg_lineBasisBezier(path, x, y) {
+  path.push(
+      "C", d3_svg_lineDot4(d3_svg_lineBasisBezier1, x),
+      ",", d3_svg_lineDot4(d3_svg_lineBasisBezier1, y),
+      ",", d3_svg_lineDot4(d3_svg_lineBasisBezier2, x),
+      ",", d3_svg_lineDot4(d3_svg_lineBasisBezier2, y),
+      ",", d3_svg_lineDot4(d3_svg_lineBasisBezier3, x),
+      ",", d3_svg_lineDot4(d3_svg_lineBasisBezier3, y));
+}
+
+// Computes the slope from points p0 to p1.
+function d3_svg_lineSlope(p0, p1) {
+  return (p1[1] - p0[1]) / (p1[0] - p0[0]);
+}
+
+// Compute three-point differences for the given points.
+// http://en.wikipedia.org/wiki/Cubic_Hermite_spline#Finite_difference
+function d3_svg_lineFiniteDifferences(points) {
+  var i = 0,
+      j = points.length - 1,
+      m = [],
+      p0 = points[0],
+      p1 = points[1],
+      d = m[0] = d3_svg_lineSlope(p0, p1);
+  while (++i < j) {
+    m[i] = d + (d = d3_svg_lineSlope(p0 = p1, p1 = points[i + 1]));
+  }
+  m[i] = d;
+  return m;
+}
+
+// Interpolates the given points using Fritsch-Carlson Monotone cubic Hermite
+// interpolation. Returns an array of tangent vectors. For details, see
+// http://en.wikipedia.org/wiki/Monotone_cubic_interpolation
+function d3_svg_lineMonotoneTangents(points) {
+  var tangents = [],
+      d,
+      a,
+      b,
+      s,
+      m = d3_svg_lineFiniteDifferences(points),
+      i = -1,
+      j = points.length - 1;
+
+  // The first two steps are done by computing finite-differences:
+  // 1. Compute the slopes of the secant lines between successive points.
+  // 2. Initialize the tangents at every point as the average of the secants.
+
+  // Then, for each segment…
+  while (++i < j) {
+    d = d3_svg_lineSlope(points[i], points[i + 1]);
+
+    // 3. If two successive yk = y{k + 1} are equal (i.e., d is zero), then set
+    // mk = m{k + 1} = 0 as the spline connecting these points must be flat to
+    // preserve monotonicity. Ignore step 4 and 5 for those k.
+
+    if (Math.abs(d) < 1e-6) {
+      m[i] = m[i + 1] = 0;
+    } else {
+      // 4. Let ak = mk / dk and bk = m{k + 1} / dk.
+      a = m[i] / d;
+      b = m[i + 1] / d;
+
+      // 5. Prevent overshoot and ensure monotonicity by restricting the
+      // magnitude of vector <ak, bk> to a circle of radius 3.
+      s = a * a + b * b;
+      if (s > 9) {
+        s = d * 3 / Math.sqrt(s);
+        m[i] = s * a;
+        m[i + 1] = s * b;
+      }
+    }
+  }
+
+  // Compute the normalized tangent vector from the slopes. Note that if x is
+  // not monotonic, it's possible that the slope will be infinite, so we protect
+  // against NaN by setting the coordinate to zero.
+  i = -1; while (++i <= j) {
+    s = (points[Math.min(j, i + 1)][0] - points[Math.max(0, i - 1)][0])
+      / (6 * (1 + m[i] * m[i]));
+    tangents.push([s || 0, m[i] * s || 0]);
+  }
+
+  return tangents;
+}
+
+function d3_svg_lineMonotone(points) {
+  return points.length < 3
+      ? d3_svg_lineLinear(points)
+      : points[0] +
+        d3_svg_lineHermite(points, d3_svg_lineMonotoneTangents(points));
+}