toolkit/javascript/d3/examples/zoom/zoom.html
changeset 47 c0b4a8b5a012
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/toolkit/javascript/d3/examples/zoom/zoom.html	Thu Apr 10 14:20:23 2014 +0200
@@ -0,0 +1,162 @@
+<!DOCTYPE html>
+<html>
+  <head>
+    <meta http-equiv="Content-Type" content="text/html;charset=utf-8">
+    <title>Zoom</title>
+    <script type="text/javascript" src="../../d3.js"></script>
+    <script type="text/javascript" src="../../d3.csv.js"></script>
+    <script type="text/javascript" src="../../d3.time.js"></script>
+    <style type="text/css">
+
+path {
+  fill: steelblue;
+}
+
+line {
+  stroke: #000;
+  shape-rendering: crispEdges;
+}
+
+    </style>
+  </head>
+  <body>
+    <script type="text/javascript">
+
+var w = 960,
+    h1 = 400,
+    h2 = 40,
+    p = 20,
+    x0, // start of focus region
+    x1, // end of focus region
+    xx, // drag state
+    time = d3.time.format("%Y-%m-%d"),
+    x = d3.scale.linear().range([0, w]),
+    y1 = d3.scale.linear().range([h1 - p, 0]),
+    y2 = d3.scale.linear().range([h2, 0]);
+
+var svg = d3.select("body")
+  .append("svg:svg")
+    .attr("width", w)
+    .attr("height", h1 + h2);
+
+// Focus view.
+var focus = svg.append("svg:g");
+
+// Context view.
+var context = svg.append("svg:g")
+    .attr("transform", "translate(0," + h1 + ")");
+
+d3.csv("dji.csv", function(csv) {
+  var minX,
+      maxX,
+      maxY = -Infinity;
+
+  // Compute x- and y-extent.
+  csv.reverse();
+  for (var i = 0, n = csv.length, o; i < n; i++) {
+    o = csv[i];
+    o = csv[i] = {x: +time.parse(o.Date), y: +o.Close};
+    if (o.y > maxY) maxY = o.y;
+  }
+  minX = csv[0].x;
+  maxX = csv[n - 1].x;
+
+  // Update x- and y-scales.
+  x.domain([minX, maxX]);
+  y1.domain([0, maxY]);
+  y2.domain([0, maxY]);
+
+  // Focus view.
+  focus.append("svg:path")
+      .data([csv])
+      .attr("d", d3.svg.area()
+      .x(function(d) { return x(d.x); })
+      .y0(y1(0))
+      .y1(function(d) { return y1(d.y); }));
+
+  focus.append("svg:line")
+      .attr("x1", 0)
+      .attr("x2", w)
+      .attr("y1", y1(0))
+      .attr("y2", y1(0));
+
+  // Context view.
+  context.append("svg:rect")
+      .attr("width", w)
+      .attr("height", h2)
+      .attr("fill", "none")
+      .attr("pointer-events", "all")
+      .attr("cursor", "crosshair")
+      .on("mousedown", mousedown);
+
+  context.append("svg:path")
+      .data([csv])
+      .attr("pointer-events", "none")
+      .attr("d", d3.svg.area()
+      .x(function(d) { return x(d.x); })
+      .y0(y2(0))
+      .y1(function(d) { return y2(d.y); }));
+
+  context.append("svg:line")
+      .attr("x1", 0)
+      .attr("x2", w)
+      .attr("y1", y2(0))
+      .attr("y2", y2(0));
+
+  // Active focus region.
+  active = context.append("svg:rect")
+      .attr("pointer-events", "none")
+      .attr("id", "active")
+      .attr("x", x(x0 = minX))
+      .attr("y", 0)
+      .attr("height", h2)
+      .attr("width", x(x1 = (minX + 1e11)) - x(x0))
+      .attr("fill", "lightcoral")
+      .attr("fill-opacity", .5);
+});
+
+d3.select(window)
+    .on("mousemove", mousemove)
+    .on("mouseup", mouseup);
+
+function mousedown() {
+  xx = x.invert(d3.svg.mouse(this)[0]);
+}
+
+function mousemove() {
+  if (xx != null) {
+
+    // Compute the new (clamped) focus region.
+    var xy = x.invert(d3.svg.mouse(active[0][0])[0]);
+    if (xx < xy) { x0 = xx; x1 = xy; }
+    else if (xx > xy) { x0 = xy; x1 = xx; }
+    else return;
+    x0 = Math.max(x.domain()[0], x0);
+    x1 = Math.min(x.domain()[1], x1);
+
+    // Update the x-scale. TODO Recycle this scale?
+    var tx = d3.scale.linear()
+        .domain([x0, x1])
+        .range([0, w]);
+
+    // Recompute the focus path.
+    focus.select("path")
+        .attr("d", d3.svg.area()
+        .x(function(d) { return tx(d.x); })
+        .y0(y1(0))
+        .y1(function(d) { return y1(d.y); }));
+
+    // Reposition the active region rect.
+    active
+        .attr("x", x(x0))
+        .attr("width", x(x1) - x(x0));
+  }
+}
+
+function mouseup() {
+  xx = null;
+}
+
+    </script>
+  </body>
+</html>