Fix issue 139:set fill option by series rather than for entire graph

[dygraphs.git] / auto_tests / tests / per_series.js

diff --git a/auto_tests/tests/per_series.js b/auto_tests/tests/per_series.js
new file mode 100644 (file)
index 0000000..3b6ee54
--- /dev/null
+++ b/auto_tests/tests/per_series.js
@@ -0,0 +1,87 @@
+/**
+ * @fileoverview FILL THIS IN
+ *
+ * @author danvk@google.com (Dan Vanderkam)
+ */
+var perSeriesTestCase = TestCase("per-series");
+
+perSeriesTestCase.prototype.setUp = function() {
+  document.body.innerHTML = "<div id='graph'></div>";
+};
+
+perSeriesTestCase.prototype.tearDown = function() {
+};
+
+/**
+ * @constructor
+ */
+var PixelSampler = function(dygraph) {
+  this.dygraph_ = dygraph;
+
+  var canvas = dygraph.hidden_;
+  var ctx = canvas.getContext("2d");
+  this.imageData_ = ctx.getImageData(0, 0, canvas.width, canvas.height);
+};
+
+/**
+ * @param {number} x The screen x-coordinate at which to sample.
+ * @param {number} y The screen y-coordinate at which to sample.
+ * @return {Array.<number>} a 4D array: [R, G, B, alpha]. All four values
+ * are in [0, 255]. A pixel which has never been touched will be [0,0,0,0].
+ */
+PixelSampler.prototype.colorAtPixel = function(x, y) {
+  var i = 4 * (x + this.imageData_.width * y);
+  var d = this.imageData_.data;
+  return [d[i], d[i+1], d[i+2], d[i+3]];
+};
+
+/**
+ * The method samples a color using data coordinates (not screen coordinates).
+ * This will round your data coordinates to the nearest screen pixel before
+ * sampling.
+ * @param {number} x The data x-coordinate at which to sample.
+ * @param {number} y The data y-coordinate at which to sample.
+ * @return {Array.<number>} a 4D array: [R, G, B, alpha]. All four values
+ * are in [0, 255]. A pixel which has never been touched will be [0,0,0,0].
+ */
+PixelSampler.prototype.colorAtCoordinate = function(x, y) {
+  var dom_xy = this.dygraph_.toDomCoords(x, y);
+  return this.colorAtPixel(Math.round(dom_xy[0]), Math.round(dom_xy[1]));
+};
+
+
+perSeriesTestCase.prototype.testPerSeriesFill = function() {
+  var opts = {
+    width: 480,
+    height: 320,
+    drawXGrid: false,
+    drawYGrid: false,
+    drawXAxis: false,
+    drawYAxis: false,
+    Y: { fillGraph: true },
+    colors: [ '#FF0000', '#0000FF' ],
+    fillAlpha: 0.15
+  };
+  var data = "X,Y,Z\n" +
+      "1,0,0\n" +
+      "2,0,1\n" +
+      "3,0,1\n" +
+      "4,0,0\n" +
+      "5,0,0\n" +
+      "6,1,0\n" +
+      "7,1,0\n" +
+      "8,0,0\n"
+  ;
+
+  var graph = document.getElementById("graph");
+  g = new Dygraph(graph, data, opts);
+
+  var sampler = new PixelSampler(g);
+
+  // Inside of the "Z" bump -- no fill.
+  assertEquals([0,0,0,0], sampler.colorAtCoordinate(2.5, 0.5));
+
+  // Inside of the "Y" bump -- filled in.
+  assertEquals([255,0,0,38], sampler.colorAtCoordinate(6.5, 0.5));
+};
+