Use "legend" option with "follow" value. Hide legend on deselect.

[dygraphs.git] / dygraph.js

diff --git a/dygraph.js b/dygraph.js
index 1e4891b..d95f9be 100644 (file)
--- a/dygraph.js
+++ b/dygraph.js
@@ -288,6 +288,7 @@ Dygraph.DEFAULT_ATTRS = {
 
   // TODO(danvk): support 'onmouseover' and 'never', and remove synonyms.
   legend: 'onmouseover',  // the only relevant value at the moment is 'always'.
+  legendFollow: false,
 
   stepPlot: false,
   avoidMinZero: false,
@@ -585,6 +586,22 @@ Dygraph.prototype.cascadeEvents_ = function(name, extra_props) {
 };
 
 /**
+ * Fetch a plugin instance of a particular class. Only for testing.
+ * @private
+ * @param {!Class} type The type of the plugin.
+ * @return {Object} Instance of the plugin, or null if there is none.
+ */
+Dygraph.prototype.getPluginInstance_ = function(type) {
+  for (var i = 0; i < this.plugins_.length; i++) {
+    var p = this.plugins_[i];
+    if (p.plugin instanceof type) {
+      return p.plugin;
+    }
+  }
+  return null;
+};
+
+/**
  * Returns the zoomed status of the chart for one or both axes.
  *
  * Axis is an optional parameter. Can be set to 'x' or 'y'.
@@ -1042,11 +1059,11 @@ Dygraph.prototype.createInterface_ = function() {
   // ... and for static parts of the chart.
   this.hidden_ = this.createPlotKitCanvas_(this.canvas_);
 
-  this.resizeElements_();
-
   this.canvas_ctx_ = Dygraph.getContext(this.canvas_);
   this.hidden_ctx_ = Dygraph.getContext(this.hidden_);
 
+  this.resizeElements_();
+
   // The interactive parts of the graph are drawn on top of the chart.
   this.graphDiv.appendChild(this.hidden_);
   this.graphDiv.appendChild(this.canvas_);
@@ -1092,14 +1109,24 @@ Dygraph.prototype.createInterface_ = function() {
 Dygraph.prototype.resizeElements_ = function() {
   this.graphDiv.style.width = this.width_ + "px";
   this.graphDiv.style.height = this.height_ + "px";
-  this.canvas_.width = this.width_;
-  this.canvas_.height = this.height_;
+
+  var canvasScale = Dygraph.getContextPixelRatio(this.canvas_ctx_);
+  this.canvas_.width = this.width_ * canvasScale;
+  this.canvas_.height = this.height_ * canvasScale;
   this.canvas_.style.width = this.width_ + "px";    // for IE
   this.canvas_.style.height = this.height_ + "px";  // for IE
-  this.hidden_.width = this.width_;
-  this.hidden_.height = this.height_;
+  if (canvasScale !== 1) {
+    this.canvas_ctx_.scale(canvasScale, canvasScale);
+  }
+
+  var hiddenScale = Dygraph.getContextPixelRatio(this.hidden_ctx_);
+  this.hidden_.width = this.width_ * hiddenScale;
+  this.hidden_.height = this.height_ * hiddenScale;
   this.hidden_.style.width = this.width_ + "px";    // for IE
   this.hidden_.style.height = this.height_ + "px";  // for IE
+  if (hiddenScale !== 1) {
+    this.hidden_ctx_.scale(hiddenScale, hiddenScale);
+  }
 };
 
 /**
@@ -2011,7 +2038,7 @@ Dygraph.prototype.updateSelection_ = function(opt_animFraction) {
       ctx.lineWidth = this.getNumericOption('strokeWidth', pt.name);
       ctx.strokeStyle = color;
       ctx.fillStyle = color;
-      callback(this.g, pt.name, ctx, canvasx, pt.canvasy,
+      callback(this, pt.name, ctx, canvasx, pt.canvasy,
           color, circleSize, pt.idx);
     }
     ctx.restore();
@@ -2350,18 +2377,22 @@ Dygraph.stackPoints_ = function(
 
     var actualYval = point.yval;
     if (isNaN(actualYval) || actualYval === null) {
-      // Interpolate/extend for stacking purposes if possible.
-      updateNextPoint(i);
-      if (prevPoint && nextPoint && fillMethod != 'none') {
-        // Use linear interpolation between prevPoint and nextPoint.
-        actualYval = prevPoint.yval + (nextPoint.yval - prevPoint.yval) *
-            ((xval - prevPoint.xval) / (nextPoint.xval - prevPoint.xval));
-      } else if (prevPoint && fillMethod == 'all') {
-        actualYval = prevPoint.yval;
-      } else if (nextPoint && fillMethod == 'all') {
-        actualYval = nextPoint.yval;
-      } else {
+      if(fillMethod == 'none') {
         actualYval = 0;
+      } else {
+        // Interpolate/extend for stacking purposes if possible.
+        updateNextPoint(i);
+        if (prevPoint && nextPoint && fillMethod != 'none') {
+          // Use linear interpolation between prevPoint and nextPoint.
+          actualYval = prevPoint.yval + (nextPoint.yval - prevPoint.yval) *
+              ((xval - prevPoint.xval) / (nextPoint.xval - prevPoint.xval));
+        } else if (prevPoint && fillMethod == 'all') {
+          actualYval = prevPoint.yval;
+        } else if (nextPoint && fillMethod == 'all') {
+          actualYval = nextPoint.yval;
+        } else {
+          actualYval = 0;
+        }
       }
     } else {
       prevPoint = point;