From: Dan Vanderkam <dan@dygraphs.com>
Date: Fri, 6 Jul 2012 03:26:49 +0000 (-0700)
Subject: Axes mostly working; some remaining issues with secondary y-axis and space reservation
X-Git-Tag: v1.0.0~245
X-Git-Url: https://adrianiainlam.tk/git/?a=commitdiff_plain;h=f8540c66c5b87d5e88d31a800dc7af237bf01213;p=dygraphs.git

Axes mostly working; some remaining issues with secondary y-axis and space reservation
---

diff --git a/dygraph-canvas.js b/dygraph-canvas.js
index 8c44f56..7acaa19 100644
--- a/dygraph-canvas.js
+++ b/dygraph-canvas.js
@@ -228,7 +228,7 @@ DygraphCanvasRenderer.prototype.render = function() {
 
   // Do the ordinary rendering, as before
   this._renderLineChart();
-  this._renderAxis();
+  // this._renderAxis();
 };
 
 DygraphCanvasRenderer.prototype._createIEClipArea = function() {
diff --git a/dygraph-dev.js b/dygraph-dev.js
index 21bc470..05ff1b5 100644
--- a/dygraph-dev.js
+++ b/dygraph-dev.js
@@ -28,6 +28,7 @@
     "dygraph-range-selector.js",
     "dygraph-tickers.js",
     "plugins/base.js",
+    "plugins/axes.js",
     "plugins/legend.js",
     "plugins/chart-labels.js",
     "plugins/annotations.js",
diff --git a/dygraph-layout.js b/dygraph-layout.js
index c6d8297..fe831a6 100644
--- a/dygraph-layout.js
+++ b/dygraph-layout.js
@@ -63,9 +63,12 @@ DygraphLayout.prototype.computePlotArea_ = function() {
     x: 0,
     y: 0
   };
+
+  /*
   if (this.attr_('drawYAxis')) {
    area.x = this.attr_('yAxisLabelWidth') + 2 * this.attr_('axisTickSize');
   }
+  */
 
   area.w = this.dygraph_.width_ - area.x - this.attr_('rightGap');
   area.h = this.dygraph_.height_;
@@ -121,6 +124,7 @@ DygraphLayout.prototype.computePlotArea_ = function() {
   };
   this.dygraph_.cascadeEvents_('layout', e);
 
+  /*
   if (this.attr_('drawXAxis')) {
     if (this.attr_('xAxisHeight')) {
       area.h -= this.attr_('xAxisHeight');
@@ -128,6 +132,7 @@ DygraphLayout.prototype.computePlotArea_ = function() {
       area.h -= this.attr_('axisLabelFontSize') + 2 * this.attr_('axisTickSize');
     }
   }
+  */
 
   // Shrink the drawing area to accomodate additional y-axes.
   if (this.dygraph_.numAxes() == 2) {
diff --git a/generate-combined.sh b/generate-combined.sh
index a065ffa..c8cda6c 100755
--- a/generate-combined.sh
+++ b/generate-combined.sh
@@ -17,6 +17,7 @@ dygraph-tickers.js \
 rgbcolor/rgbcolor.js \
 strftime/strftime-min.js \
 plugins/base.js \
+plugins/axes.js \
 plugins/legend.js \
 plugins/chart-labels \
 plugins/annotations.js \
diff --git a/plugins/axes.js b/plugins/axes.js
new file mode 100644
index 0000000..0c81759
--- /dev/null
+++ b/plugins/axes.js
@@ -0,0 +1,272 @@
+/**
+ * @license
+ * Copyright 2012 Dan Vanderkam (danvdk@gmail.com)
+ * MIT-licensed (http://opensource.org/licenses/MIT)
+ */
+
+Dygraph.Plugins.Axes = (function() {
+
+/*
+
+Bits of jankiness:
+- Direct layout access
+- Direct area access
+- Should include calculation of ticks, not just the drawing.
+
+*/
+
+/**
+ * Draws the axes. This includes the labels on the x- and y-axes, as well
+ * as the tick marks on the axes.
+ * It does _not_ draw the grid lines which span the entire chart.
+ */
+var axes = function() {
+  this.xlabels_ = [];
+  this.ylabels_ = [];
+};
+
+axes.prototype.toString = function() {
+  return "Axes Plugin";
+};
+
+axes.prototype.activate = function(g) {
+  return {
+    layout: this.layout,
+    clearChart: this.clearChart,
+    drawChart: this.drawChart
+  };
+};
+
+axes.prototype.layout = function(e) {
+  var g = e.dygraph;
+
+  if (g.getOption('drawYAxis')) {
+    var w = g.getOption('yAxisLabelWidth') + 2 * g.getOption('axisTickSize');
+    var y_axis_rect = e.reserveSpaceLeft(w);
+  }
+
+  if (g.getOption('drawXAxis')) {
+    var h;
+    if (g.getOption('xAxisHeight')) {
+      h = g.getOption('xAxisHeight');
+    } else {
+      h = g.getOption('axisLabelFontSize') + 2 * g.getOption('axisTickSize');
+    }
+    var x_axis_rect = e.reserveSpaceBottom(h);
+  }
+
+  if (g.numAxes() == 2) {
+    // TODO(danvk): per-axis setting.
+    var w = g.getOption('yAxisLabelWidth') + 2 * g.getOption('axisTickSize');
+    var y2_axis_rect = e.reserveSpaceRight(w);
+  } else if (g.numAxes() > 2) {
+    g.error("Only two y-axes are supported at this time. (Trying " +
+            "to use " + g.numAxes() + ")");
+  }
+};
+
+axes.prototype.detachLabels = function() {
+  function removeArray(ary) {
+    for (var i = 0; i < ary.length; i++) {
+      var el = ary[i];
+      if (el.parentNode) el.parentNode.removeChild(el);
+    }
+  }
+
+  removeArray(this.xlabels_);
+  removeArray(this.ylabels_);
+  this.xlabels_ = [];
+  this.ylabels_ = [];
+};
+
+axes.prototype.clearChart = function(e) {
+  var g = e.dygraph;
+  this.detachLabels();
+}
+
+axes.prototype.drawChart = function(e) {
+  var g = e.dygraph;
+  if (!g.getOption('drawXAxis') && !g.getOption('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 = e.drawingContext;
+  var containerDiv = e.canvas.parentNode;
+
+  var label, x, y, tick, i;
+
+  var labelStyle = {
+    position: "absolute",
+    fontSize: g.getOption('axisLabelFontSize') + "px",
+    zIndex: 10,
+    color: g.getOption('axisLabelColor'),
+    width: g.getOption('axisLabelWidth') + "px",
+    // height: this.attr_('axisLabelFontSize') + 2 + "px",
+    lineHeight: "normal",  // Something other than "normal" line-height screws up label positioning.
+    overflow: "hidden"
+  };
+  var makeDiv = function(txt, axis, prec_axis) {
+    var div = document.createElement("div");
+    for (var name in labelStyle) {
+      if (labelStyle.hasOwnProperty(name)) {
+        div.style[name] = labelStyle[name];
+      }
+    }
+    var inner_div = document.createElement("div");
+    inner_div.className = 'dygraph-axis-label' +
+                          ' dygraph-axis-label-' + axis +
+                          (prec_axis ? ' dygraph-axis-label-' + prec_axis : '');
+    inner_div.innerHTML = txt;
+    div.appendChild(inner_div);
+    return div;
+  };
+
+  // axis lines
+  context.save();
+  context.strokeStyle = g.getOption('axisLineColor');
+  context.lineWidth = g.getOption('axisLineWidth');
+
+  var layout = g.layout_;
+  var area = e.dygraph.plotter_.area;
+
+  if (g.getOption('drawYAxis')) {
+    if (layout.yticks && layout.yticks.length > 0) {
+      var num_axes = g.numAxes();
+      for (i = 0; i < layout.yticks.length; i++) {
+        tick = layout.yticks[i];
+        if (typeof(tick) == "function") return;
+        x = area.x;
+        var sgn = 1;
+        var prec_axis = 'y1';
+        if (tick[0] == 1) {  // right-side y-axis
+          x = area.x + area.w;
+          sgn = -1;
+          prec_axis = 'y2';
+        }
+        y = area.y + tick[1] * area.h;
+
+        /* Tick marks are currently clipped, so don't bother drawing them.
+        context.beginPath();
+        context.moveTo(halfUp(x), halfDown(y));
+        context.lineTo(halfUp(x - sgn * this.attr_('axisTickSize')), halfDown(y));
+        context.closePath();
+        context.stroke();
+        */
+
+        label = makeDiv(tick[2], 'y', num_axes == 2 ? prec_axis : null);
+        var top = (y - g.getOption('axisLabelFontSize') / 2);
+        if (top < 0) top = 0;
+
+        if (top + g.getOption('axisLabelFontSize') + 3 > this.height) {
+          label.style.bottom = "0px";
+        } else {
+          label.style.top = top + "px";
+        }
+        if (tick[0] === 0) {
+          label.style.left = (area.x - g.getOption('yAxisLabelWidth') - g.getOption('axisTickSize')) + "px";
+          label.style.textAlign = "right";
+        } else if (tick[0] == 1) {
+          label.style.left = (area.x + area.w +
+                              g.getOption('axisTickSize')) + "px";
+          label.style.textAlign = "left";
+        }
+        label.style.width = g.getOption('yAxisLabelWidth') + "px";
+        containerDiv.appendChild(label);
+        this.ylabels_.push(label);
+      }
+
+      // The lowest tick on the y-axis often overlaps with the leftmost
+      // tick on the x-axis. Shift the bottom tick up a little bit to
+      // compensate if necessary.
+      var bottomTick = this.ylabels_[0];
+      var fontSize = g.getOption('axisLabelFontSize');
+      var bottom = parseInt(bottomTick.style.top, 10) + fontSize;
+      if (bottom > this.height - fontSize) {
+        bottomTick.style.top = (parseInt(bottomTick.style.top, 10) -
+            fontSize / 2) + "px";
+      }
+    }
+
+    // draw a vertical line on the left to separate the chart from the labels.
+    var axisX;
+    if (g.getOption('drawAxesAtZero')) {
+      var r = this.dygraph_.toPercentXCoord(0);
+      if (r > 1 || r < 0) r = 0;
+      axisX = halfUp(area.x + r * area.w);
+    } else {
+      axisX = halfUp(area.x);
+    }
+    context.beginPath();
+    context.moveTo(axisX, halfDown(area.y));
+    context.lineTo(axisX, halfDown(area.y + area.h));
+    context.closePath();
+    context.stroke();
+
+    // if there's a secondary y-axis, draw a vertical line for that, too.
+    if (g.numAxes() == 2) {
+      context.beginPath();
+      context.moveTo(halfDown(area.x + area.w), halfDown(area.y));
+      context.lineTo(halfDown(area.x + area.w), halfDown(area.y + area.h));
+      context.closePath();
+      context.stroke();
+    }
+  }
+
+  if (g.getOption('drawXAxis')) {
+    if (layout.xticks) {
+      for (i = 0; i < layout.xticks.length; i++) {
+        tick = layout.xticks[i];
+        x = area.x + tick[0] * area.w;
+        y = area.y + area.h;
+
+        /* Tick marks are currently clipped, so don't bother drawing them.
+        context.beginPath();
+        context.moveTo(halfUp(x), halfDown(y));
+        context.lineTo(halfUp(x), halfDown(y + this.attr_('axisTickSize')));
+        context.closePath();
+        context.stroke();
+        */
+
+        label = makeDiv(tick[1], 'x');
+        label.style.textAlign = "center";
+        label.style.top = (y + g.getOption('axisTickSize')) + 'px';
+
+        var left = (x - g.getOption('axisLabelWidth')/2);
+        if (left + g.getOption('axisLabelWidth') > this.width) {
+          left = this.width - g.getOption('xAxisLabelWidth');
+          label.style.textAlign = "right";
+        }
+        if (left < 0) {
+          left = 0;
+          label.style.textAlign = "left";
+        }
+
+        label.style.left = left + "px";
+        label.style.width = g.getOption('xAxisLabelWidth') + "px";
+        containerDiv.appendChild(label);
+        this.xlabels_.push(label);
+      }
+    }
+
+    context.beginPath();
+    var axisY;
+    if (g.getOption('drawAxesAtZero')) {
+      var r = g.toPercentYCoord(0, 0);
+      if (r > 1 || r < 0) r = 1;
+      axisY = halfDown(area.y + r * area.h);
+    } else {
+      axisY = halfDown(area.y + area.h);
+    }
+    context.moveTo(halfUp(area.x), axisY);
+    context.lineTo(halfUp(area.x + area.w), axisY);
+    context.closePath();
+    context.stroke();
+  }
+
+  context.restore();
+}
+
+return axes;
+})();
diff --git a/plugins/install.js b/plugins/install.js
index 4e962a1..c87b06e 100644
--- a/plugins/install.js
+++ b/plugins/install.js
@@ -1,6 +1,16 @@
+// This file defines the ordering of the plugins.
+//
+// The ordering is from most-general to most-specific.
+// This means that, in an event cascade, plugins which have registered for that
+// event will be called in reverse order.
+//
+// This is most relevant for plugins which register a layout event, e.g.
+// Axes, Legend and ChartLabels.
+
 // TODO(danvk): move this into the top-level directory. Only plugins here.
 Dygraph.PLUGINS.push(
   Dygraph.Plugins.Legend,
+  Dygraph.Plugins.Axes,
   Dygraph.Plugins.ChartLabels,
   Dygraph.Plugins.Annotations
 );