X-Git-Url: https://adrianiainlam.tk/git/?a=blobdiff_plain;f=dygraph-canvas.js;h=2f8821e17fad93e0d16d743508c6e04eb2119f6c;hb=54425b14df388e9337a1d77876512bb60ba74c3b;hp=fb724e1e8bef01d23543dc6df0753058c6475c54;hpb=fb25c8b6d070c7e347b260ef39917220b6159e4e;p=dygraphs.git

diff --git a/dygraph-canvas.js b/dygraph-canvas.js
index fb724e1..2f8821e 100644
--- a/dygraph-canvas.js
+++ b/dygraph-canvas.js
@@ -4,7 +4,7 @@
 /**
  * @fileoverview Based on PlotKit, but modified to meet the needs of dygraphs.
  * In particular, support for:
- * - grid overlays 
+ * - grid overlays
  * - error bars
  * - dygraphs attribute system
  */
@@ -19,7 +19,7 @@ DygraphLayout = function(dygraph, options) {
   this.options = {};  // TODO(danvk): remove, use attr_ instead.
   Dygraph.update(this.options, options ? options : {});
   this.datasets = new Array();
-  this.annotations = new Array()
+  this.annotations = new Array();
 };
 
 DygraphLayout.prototype.attr_ = function(name) {
@@ -32,8 +32,9 @@ DygraphLayout.prototype.addDataset = function(setname, set_xy) {
 
 DygraphLayout.prototype.setAnnotations = function(ann) {
   // The Dygraph object's annotations aren't parsed. We parse them here and
-  // save a copy.
-  var parse = this.attr_('xValueParser');
+  // save a copy. If there is no parser, then the user must be using raw format.
+  this.annotations = [];
+  var parse = this.attr_('xValueParser') || function(x) { return x; };
   for (var i = 0; i < ann.length; i++) {
     var a = {};
     if (!ann[i].xval && !ann[i].x) {
@@ -69,20 +70,35 @@ DygraphLayout.prototype._evaluateLimits = function() {
     for (var name in this.datasets) {
       if (!this.datasets.hasOwnProperty(name)) continue;
       var series = this.datasets[name];
-      var x1 = series[0][0];
-      if (!this.minxval || x1 < this.minxval) this.minxval = x1;
-
-      var x2 = series[series.length - 1][0];
-      if (!this.maxxval || x2 > this.maxxval) this.maxxval = x2;
+      if (series.length > 1) {
+        var x1 = series[0][0];
+        if (!this.minxval || x1 < this.minxval) this.minxval = x1;
+  
+        var x2 = series[series.length - 1][0];
+        if (!this.maxxval || x2 > this.maxxval) this.maxxval = x2;
+      }
     }
   }
   this.xrange = this.maxxval - this.minxval;
   this.xscale = (this.xrange != 0 ? 1/this.xrange : 1.0);
 
-  this.minyval = this.options.yAxis[0];
-  this.maxyval = this.options.yAxis[1];
-  this.yrange = this.maxyval - this.minyval;
-  this.yscale = (this.yrange != 0 ? 1/this.yrange : 1.0);
+  for (var i = 0; i < this.options.yAxes.length; i++) {
+    var axis = this.options.yAxes[i];
+    axis.minyval = axis.computedValueRange[0];
+    axis.maxyval = axis.computedValueRange[1];
+    axis.yrange = axis.maxyval - axis.minyval;
+    axis.yscale = (axis.yrange != 0 ? 1.0 / axis.yrange : 1.0);
+
+    if (axis.g.attr_("logscale")) {
+      axis.ylogrange = Dygraph.log10(axis.maxyval) - Dygraph.log10(axis.minyval);
+      axis.ylogscale = (axis.ylogrange != 0 ? 1.0 / axis.ylogrange : 1.0);
+      if (!isFinite(axis.ylogrange) || isNaN(axis.ylogrange)) {
+        axis.g.error('axis ' + i + ' of graph at ' + axis.g +
+            ' can\'t be displayed in log scale for range [' +
+            axis.minyval + ' - ' + axis.maxyval + ']');
+      }
+    }
+  }
 };
 
 DygraphLayout.prototype._evaluateLineCharts = function() {
@@ -92,24 +108,26 @@ DygraphLayout.prototype._evaluateLineCharts = function() {
     if (!this.datasets.hasOwnProperty(setName)) continue;
 
     var dataset = this.datasets[setName];
+    var axis = this.options.yAxes[this.options.seriesToAxisMap[setName]];
+
     for (var j = 0; j < dataset.length; j++) {
       var item = dataset[j];
+
+      var yval;
+      if (axis.logscale) {
+        yval = 1.0 - ((Dygraph.log10(parseFloat(item[1])) - Dygraph.log10(axis.minyval)) * axis.ylogscale); // really should just be yscale.
+      } else {
+        yval = 1.0 - ((parseFloat(item[1]) - axis.minyval) * axis.yscale);
+      }
       var point = {
         // TODO(danvk): here
         x: ((parseFloat(item[0]) - this.minxval) * this.xscale),
-        y: 1.0 - ((parseFloat(item[1]) - this.minyval) * this.yscale),
+        y: yval,
         xval: parseFloat(item[0]),
         yval: parseFloat(item[1]),
         name: setName
       };
 
-      // limit the x, y values so they do not overdraw
-      if (point.y <= 0.0) {
-        point.y = 0.0;
-      }
-      if (point.y >= 1.0) {
-        point.y = 1.0;
-      }
       this.points.push(point);
     }
   }
@@ -127,12 +145,15 @@ DygraphLayout.prototype._evaluateLineTicks = function() {
   }
 
   this.yticks = new Array();
-  for (var i = 0; i < this.options.yTicks.length; i++) {
-    var tick = this.options.yTicks[i];
-    var label = tick.label;
-    var pos = 1.0 - (this.yscale * (tick.v - this.minyval));
-    if ((pos >= 0.0) && (pos <= 1.0)) {
-      this.yticks.push([pos, label]);
+  for (var i = 0; i < this.options.yAxes.length; i++ ) {
+    var axis = this.options.yAxes[i];
+    for (var j = 0; j < axis.ticks.length; j++) {
+      var tick = axis.ticks[j];
+      var label = tick.label;
+      var pos = this.dygraph_.toPercentYCoord(tick.v, i);
+      if ((pos >= 0.0) && (pos <= 1.0)) {
+        this.yticks.push([i, pos, label]);
+      }
     }
   }
 };
@@ -281,7 +302,9 @@ DygraphCanvasRenderer = function(dygraph, element, layout, options) {
   this.ylabels = new Array();
   this.annotations = new Array();
 
+  // TODO(danvk): consider all axes in this computation.
   this.area = {
+    // TODO(danvk): per-axis setting.
     x: this.options.yAxisLabelWidth + 2 * this.options.axisTickSize,
     y: 0
   };
@@ -289,8 +312,33 @@ DygraphCanvasRenderer = function(dygraph, element, layout, options) {
   this.area.h = this.height - this.options.axisLabelFontSize -
                 2 * this.options.axisTickSize;
 
+  // Shrink the drawing area to accomodate additional y-axes.
+  if (this.dygraph_.numAxes() == 2) {
+    // TODO(danvk): per-axis setting.
+    this.area.w -= (this.options.yAxisLabelWidth + 2 * this.options.axisTickSize);
+  } else if (this.dygraph_.numAxes() > 2) {
+    this.dygraph_.error("Only two y-axes are supported at this time. (Trying " +
+                        "to use " + this.dygraph_.numAxes() + ")");
+  }
+
   this.container.style.position = "relative";
   this.container.style.width = this.width + "px";
+
+  // Set up a clipping area for the canvas (and the interaction canvas).
+  // This ensures that we don't overdraw.
+  var ctx = this.dygraph_.canvas_.getContext("2d");
+  ctx.beginPath();
+  ctx.rect(this.area.x, this.area.y, this.area.w, this.area.h);
+  ctx.clip();
+
+  ctx = this.dygraph_.hidden_.getContext("2d");
+  ctx.beginPath();
+  ctx.rect(this.area.x, this.area.y, this.area.w, this.area.h);
+  ctx.clip();
+};
+
+DygraphCanvasRenderer.prototype.attr_ = function(x) {
+  return this.dygraph_.attr_(x);
 };
 
 DygraphCanvasRenderer.prototype.clear = function() {
@@ -316,15 +364,15 @@ DygraphCanvasRenderer.prototype.clear = function() {
 
   for (var i = 0; i < this.xlabels.length; i++) {
     var el = this.xlabels[i];
-    el.parentNode.removeChild(el);
+    if (el.parentNode) el.parentNode.removeChild(el);
   }
   for (var i = 0; i < this.ylabels.length; i++) {
     var el = this.ylabels[i];
-    el.parentNode.removeChild(el);
+    if (el.parentNode) el.parentNode.removeChild(el);
   }
   for (var i = 0; i < this.annotations.length; i++) {
     var el = this.annotations[i];
-    el.parentNode.removeChild(el);
+    if (el.parentNode) el.parentNode.removeChild(el);
   }
   this.xlabels = new Array();
   this.ylabels = new Array();
@@ -355,11 +403,16 @@ DygraphCanvasRenderer.isSupported = function(canvasName) {
  * Draw an X/Y grid on top of the existing plot
  */
 DygraphCanvasRenderer.prototype.render = function() {
-  // Draw the new X/Y grid
+  // Draw the new X/Y grid. Lines appear crisper when pixels are rounded to
+  // half-integers. This prevents them from drawing in two rows/cols.
   var ctx = this.element.getContext("2d");
+  function halfUp(x){return Math.round(x)+0.5};
+  function halfDown(y){return Math.round(y)-0.5};
 
   if (this.options.underlayCallback) {
-    this.options.underlayCallback(ctx, this.area, this.layout, this.dygraph_);
+    // NOTE: we pass the dygraph object to this callback twice to avoid breaking
+    // users who expect a deprecated form of this callback.
+    this.options.underlayCallback(ctx, this.area, this.dygraph_, this.dygraph_);
   }
 
   if (this.options.drawYGrid) {
@@ -368,8 +421,10 @@ DygraphCanvasRenderer.prototype.render = function() {
     ctx.strokeStyle = this.options.gridLineColor;
     ctx.lineWidth = this.options.axisLineWidth;
     for (var i = 0; i < ticks.length; i++) {
-      var x = this.area.x;
-      var y = this.area.y + ticks[i][0] * this.area.h;
+      // TODO(danvk): allow secondary axes to draw a grid, too.
+      if (ticks[i][0] != 0) continue;
+      var x = halfUp(this.area.x);
+      var y = halfDown(this.area.y + ticks[i][1] * this.area.h);
       ctx.beginPath();
       ctx.moveTo(x, y);
       ctx.lineTo(x + this.area.w, y);
@@ -384,8 +439,8 @@ DygraphCanvasRenderer.prototype.render = function() {
     ctx.strokeStyle = this.options.gridLineColor;
     ctx.lineWidth = this.options.axisLineWidth;
     for (var i=0; i<ticks.length; i++) {
-      var x = this.area.x + ticks[i][0] * this.area.w;
-      var y = this.area.y + this.area.h;
+      var x = halfUp(this.area.x + ticks[i][0] * this.area.w);
+      var y = halfDown(this.area.y + this.area.h);
       ctx.beginPath();
       ctx.moveTo(x, y);
       ctx.lineTo(x, this.area.y);
@@ -405,6 +460,10 @@ DygraphCanvasRenderer.prototype._renderAxis = function() {
   if (!this.options.drawXAxis && !this.options.drawYAxis)
     return;
 
+  // Round pixels to half-integer boundaries for crisper drawing.
+  function halfUp(x){return Math.round(x)+0.5};
+  function halfDown(y){return Math.round(y)-0.5};
+
   var context = this.element.getContext("2d");
 
   var labelStyle = {
@@ -437,14 +496,19 @@ DygraphCanvasRenderer.prototype._renderAxis = function() {
         var tick = this.layout.yticks[i];
         if (typeof(tick) == "function") return;
         var x = this.area.x;
-        var y = this.area.y + tick[0] * this.area.h;
+        var sgn = 1;
+        if (tick[0] == 1) {  // right-side y-axis
+          x = this.area.x + this.area.w;
+          sgn = -1;
+        }
+        var y = this.area.y + tick[1] * this.area.h;
         context.beginPath();
-        context.moveTo(x, y);
-        context.lineTo(x - this.options.axisTickSize, y);
+        context.moveTo(halfUp(x), halfDown(y));
+        context.lineTo(halfUp(x - sgn * this.options.axisTickSize), halfDown(y));
         context.closePath();
         context.stroke();
 
-        var label = makeDiv(tick[1]);
+        var label = makeDiv(tick[2]);
         var top = (y - this.options.axisLabelFontSize / 2);
         if (top < 0) top = 0;
 
@@ -453,8 +517,14 @@ DygraphCanvasRenderer.prototype._renderAxis = function() {
         } else {
           label.style.top = top + "px";
         }
-        label.style.left = "0px";
-        label.style.textAlign = "right";
+        if (tick[0] == 0) {
+          label.style.left = "0px";
+          label.style.textAlign = "right";
+        } else if (tick[0] == 1) {
+          label.style.left = (this.area.x + this.area.w +
+                              this.options.axisTickSize) + "px";
+          label.style.textAlign = "left";
+        }
         label.style.width = this.options.yAxisLabelWidth + "px";
         this.container.appendChild(label);
         this.ylabels.push(label);
@@ -472,11 +542,21 @@ DygraphCanvasRenderer.prototype._renderAxis = function() {
       }
     }
 
+    // draw a vertical line on the left to separate the chart from the labels.
     context.beginPath();
-    context.moveTo(this.area.x, this.area.y);
-    context.lineTo(this.area.x, this.area.y + this.area.h);
+    context.moveTo(halfUp(this.area.x), halfDown(this.area.y));
+    context.lineTo(halfUp(this.area.x), halfDown(this.area.y + this.area.h));
     context.closePath();
     context.stroke();
+
+    // if there's a secondary y-axis, draw a vertical line for that, too.
+    if (this.dygraph_.numAxes() == 2) {
+      context.beginPath();
+      context.moveTo(halfDown(this.area.x + this.area.w), halfDown(this.area.y));
+      context.lineTo(halfDown(this.area.x + this.area.w), halfDown(this.area.y + this.area.h));
+      context.closePath();
+      context.stroke();
+    }
   }
 
   if (this.options.drawXAxis) {
@@ -488,8 +568,8 @@ DygraphCanvasRenderer.prototype._renderAxis = function() {
         var x = this.area.x + tick[0] * this.area.w;
         var y = this.area.y + this.area.h;
         context.beginPath();
-        context.moveTo(x, y);
-        context.lineTo(x, y + this.options.axisTickSize);
+        context.moveTo(halfUp(x), halfDown(y));
+        context.lineTo(halfUp(x), halfDown(y + this.options.axisTickSize));
         context.closePath();
         context.stroke();
 
@@ -515,8 +595,8 @@ DygraphCanvasRenderer.prototype._renderAxis = function() {
     }
 
     context.beginPath();
-    context.moveTo(this.area.x, this.area.y + this.area.h);
-    context.lineTo(this.area.x + this.area.w, this.area.y + this.area.h);
+    context.moveTo(halfUp(this.area.x), halfDown(this.area.y + this.area.h));
+    context.lineTo(halfUp(this.area.x + this.area.w), halfDown(this.area.y + this.area.h));
     context.closePath();
     context.stroke();
   }
@@ -627,12 +707,13 @@ DygraphCanvasRenderer.prototype._renderAnnotations = function() {
  * Overrides the CanvasRenderer method to draw error bars
  */
 DygraphCanvasRenderer.prototype._renderLineChart = function() {
+  // TODO(danvk): use this.attr_ for many of these.
   var context = this.element.getContext("2d");
   var colorCount = this.options.colorScheme.length;
   var colorScheme = this.options.colorScheme;
   var fillAlpha = this.options.fillAlpha;
   var errorBars = this.layout.options.errorBars;
-  var fillGraph = this.layout.options.fillGraph;
+  var fillGraph = this.attr_("fillGraph");
   var stackedGraph = this.layout.options.stackedGraph;
   var stepPlot = this.layout.options.stepPlot;
 
@@ -658,8 +739,6 @@ DygraphCanvasRenderer.prototype._renderLineChart = function() {
   }
 
   // create paths
-  var isOK = function(x) { return x && !isNaN(x); };
-
   var ctx = context;
   if (errorBars) {
     if (fillGraph) {
@@ -668,6 +747,8 @@ DygraphCanvasRenderer.prototype._renderLineChart = function() {
 
     for (var i = 0; i < setCount; i++) {
       var setName = setNames[i];
+      var axis = this.layout.options.yAxes[
+        this.layout.options.seriesToAxisMap[setName]];
       var color = this.colors[setName];
 
       // setup graphics context
@@ -675,7 +756,7 @@ DygraphCanvasRenderer.prototype._renderLineChart = function() {
       var prevX = NaN;
       var prevY = NaN;
       var prevYs = [-1, -1];
-      var yscale = this.layout.yscale;
+      var yscale = axis.yscale;
       // should be same color as the lines but only 15% opaque.
       var rgb = new RGBColor(color);
       var err_color = 'rgba(' + rgb.r + ',' + rgb.g + ',' + rgb.b + ',' +
@@ -685,7 +766,7 @@ DygraphCanvasRenderer.prototype._renderLineChart = function() {
       for (var j = 0; j < this.layout.points.length; j++) {
         var point = this.layout.points[j];
         if (point.name == setName) {
-          if (!isOK(point.y)) {
+          if (!Dygraph.isOK(point.y)) {
             prevX = NaN;
             continue;
           }
@@ -723,23 +804,24 @@ DygraphCanvasRenderer.prototype._renderLineChart = function() {
       ctx.fill();
     }
   } else if (fillGraph) {
-    var axisY = 1.0 + this.layout.minyval * this.layout.yscale;
-    if (axisY < 0.0) axisY = 0.0;
-    else if (axisY > 1.0) axisY = 1.0;
-    axisY = this.area.h * axisY + this.area.y;
-
     var baseline = []  // for stacked graphs: baseline for filling
 
     // process sets in reverse order (needed for stacked graphs)
     for (var i = setCount - 1; i >= 0; i--) {
       var setName = setNames[i];
       var color = this.colors[setName];
+      var axis = this.layout.options.yAxes[
+        this.layout.options.seriesToAxisMap[setName]];
+      var axisY = 1.0 + axis.minyval * axis.yscale;
+      if (axisY < 0.0) axisY = 0.0;
+      else if (axisY > 1.0) axisY = 1.0;
+      axisY = this.area.h * axisY + this.area.y;
 
       // setup graphics context
       ctx.save();
       var prevX = NaN;
       var prevYs = [-1, -1];
-      var yscale = this.layout.yscale;
+      var yscale = axis.yscale;
       // should be same color as the lines but only 15% opaque.
       var rgb = new RGBColor(color);
       var err_color = 'rgba(' + rgb.r + ',' + rgb.g + ',' + rgb.b + ',' +
@@ -749,7 +831,7 @@ DygraphCanvasRenderer.prototype._renderLineChart = function() {
       for (var j = 0; j < this.layout.points.length; j++) {
         var point = this.layout.points[j];
         if (point.name == setName) {
-          if (!isOK(point.y)) {
+          if (!Dygraph.isOK(point.y)) {
             prevX = NaN;
             continue;
           }
@@ -796,7 +878,7 @@ DygraphCanvasRenderer.prototype._renderLineChart = function() {
     for (var j = 0; j < points.length; j++) {
       var point = points[j];
       if (point.name == setName) {
-        if (!isOK(point.canvasy)) {
+        if (!Dygraph.isOK(point.canvasy)) {
           if (stepPlot && prevX != null) {
             // Draw a horizontal line to the start of the missing data
             ctx.beginPath();
@@ -812,7 +894,7 @@ DygraphCanvasRenderer.prototype._renderLineChart = function() {
           // A point is "isolated" if it is non-null but both the previous
           // and next points are null.
           var isIsolated = (!prevX && (j == points.length - 1 ||
-                                       !isOK(points[j+1].canvasy)));
+                                       !Dygraph.isOK(points[j+1].canvasy)));
 
           if (!prevX) {
             prevX = point.canvasx;