Make seriesToPoints_ and stackPoints_ private. They are being rendered as part of...

[dygraphs.git] / dygraph-canvas.js

diff --git a/dygraph-canvas.js b/dygraph-canvas.js
index e531ece..cba4f44 100644 (file)
--- a/dygraph-canvas.js
+++ b/dygraph-canvas.js
@@ -39,8 +39,8 @@
  * The chart canvas has already been created by the Dygraph object. The
  * renderer simply gets a drawing context.
  *
- * @param {Dyraph} dygraph The chart to which this renderer belongs.
- * @param {Canvas} element The <canvas> DOM element on which to draw.
+ * @param {Dygraph} dygraph The chart to which this renderer belongs.
+ * @param {HTMLCanvasElement} element The <canvas> DOM element on which to draw.
  * @param {CanvasRenderingContext2D} elementContext The drawing context.
  * @param {DygraphLayout} layout The chart's DygraphLayout object.
  *
@@ -57,9 +57,8 @@ var DygraphCanvasRenderer = function(dygraph, element, elementContext, layout) {
   this.height = this.element.height;
   this.width = this.element.width;
 
-  this.elementContext.save();
-
   // --- check whether everything is ok before we return
+  // NOTE(konigsberg): isIE is never defined in this object. Bug of some sort.
   if (!this.isIE && !(DygraphCanvasRenderer.isSupported(this.element)))
       throw "Canvas is not supported.";
 
@@ -127,11 +126,6 @@ DygraphCanvasRenderer.prototype.clear = function() {
   context.clearRect(0, 0, this.width, this.height);
 };
 
-DygraphCanvasRenderer.prototype.onDoneDrawing = function() {
-  // balances the save called in the constructor.
-  this.elementContext.restore();
-}
-
 /**
  * Checks whether the browser supports the <canvas> tag.
  * @private
@@ -380,7 +374,7 @@ DygraphCanvasRenderer._drawSeries = function(e,
         ctx.moveTo(point.canvasx, point.canvasy);
       }
       if (drawPoints || isIsolated) {
-        pointsOnLine.push([point.canvasx, point.canvasy]);
+        pointsOnLine.push([point.canvasx, point.canvasy, point.idx]);
       }
       prevCanvasX = point.canvasx;
       prevCanvasY = point.canvasy;
@@ -405,7 +399,7 @@ DygraphCanvasRenderer._drawPointsOnLine = function(
     var cb = pointsOnLine[idx];
     ctx.save();
     drawPointCallback(
-        e.dygraph, e.setName, ctx, cb[0], cb[1], color, pointSize);
+        e.dygraph, e.setName, ctx, cb[0], cb[1], color, pointSize, cb[2]);
     ctx.restore();
   }
 };
@@ -440,14 +434,16 @@ DygraphCanvasRenderer.prototype._updatePoints = function() {
 
 /**
  * Add canvas Actually draw the lines chart, including error bars.
- * If opt_seriesName is specified, only that series will be drawn.
- * (This is used for expedited redrawing with highlightSeriesOpts)
- * Lines are typically drawn in the non-interactive dygraph canvas. If opt_ctx
- * is specified, they can be drawn elsewhere.
  *
  * This function can only be called if DygraphLayout's points array has been
  * updated with canvas{x,y} attributes, i.e. by
  * DygraphCanvasRenderer._updatePoints.
+ *
+ * @param {string=} opt_seriesName when specified, only that series will
+ *     be drawn. (This is used for expedited redrawing with highlightSeriesOpts)
+ * @param {CanvasRenderingContext2D} opt_ctx when specified, the drawing
+ *     context.  However, lines are typically drawn on the object's
+ *     elementContext.
  * @private
  */
 DygraphCanvasRenderer.prototype._renderLineChart = function(opt_seriesName, opt_ctx) {
@@ -482,7 +478,7 @@ DygraphCanvasRenderer.prototype._renderLineChart = function(opt_seriesName, opt_
 
     for (var j = 0; j < sets.length; j++) {
       setName = setNames[j];
-      if (opt_seriesName && !(is_last && setName == opt_seriesName)) continue;
+      if (opt_seriesName && setName != opt_seriesName) continue;
 
       var points = sets[j];
 
@@ -514,6 +510,7 @@ DygraphCanvasRenderer.prototype._renderLineChart = function(opt_seriesName, opt_
         plotArea: this.area,
         seriesIndex: j,
         seriesCount: sets.length,
+        singleSeriesName: opt_seriesName,
         allSeriesPoints: sets
       });
       ctx.restore();
@@ -671,6 +668,9 @@ DygraphCanvasRenderer._errorPlotter = function(e) {
  * @private
  */
 DygraphCanvasRenderer._fillPlotter = function(e) {
+  // Skip if we're drawing a single series for interactive highlight overlay.
+  if (e.singleSeriesName) return;
+
   // We'll handle all the series at once, not one-by-one.
   if (e.seriesIndex !== 0) return;
 
@@ -702,7 +702,14 @@ DygraphCanvasRenderer._fillPlotter = function(e) {
   var stackedGraph = g.getOption("stackedGraph");
   var colors = g.getColors();
 
-  var baseline = {};  // for stacked graphs: baseline for filling
+  // For stacked graphs, track the baseline for filling.
+  //
+  // The filled areas below graph lines are trapezoids with two
+  // vertical edges. The top edge is the line segment being drawn, and
+  // the baseline is the bottom edge. Each baseline corresponds to the
+  // top line segment from the previous stacked line. In the case of
+  // step plots, the trapezoids are rectangles.
+  var baseline = {};
   var currBaseline;
   var prevStepPlot;  // for different line drawing modes (line/step) per series
 
@@ -734,13 +741,24 @@ DygraphCanvasRenderer._fillPlotter = function(e) {
         'rgba(' + rgb.r + ',' + rgb.g + ',' + rgb.b + ',' + fillAlpha + ')';
     ctx.fillStyle = err_color;
     ctx.beginPath();
-    while(iter.hasNext) {
+    var last_x, is_first = true;
+    while (iter.hasNext) {
       var point = iter.next();
       if (!Dygraph.isOK(point.y)) {
         prevX = NaN;
+        if (point.y_stacked !== null && !isNaN(point.y_stacked)) {
+          baseline[point.canvasx] = area.h * point.y_stacked + area.y;
+        }
         continue;
       }
       if (stackedGraph) {
+        if (!is_first && last_x == point.xval) {
+          continue;
+        } else {
+          is_first = false;
+          last_x = point.xval;
+        }
+
         currBaseline = baseline[point.canvasx];
         var lastY;
         if (currBaseline === undefined) {