From 70f76a25b7ad6214ab07ee0976072b6160032b94 Mon Sep 17 00:00:00 2001
From: wimrijnders <wrijnders@gmail.com>
Date: Mon, 24 Oct 2016 15:14:37 +0200
Subject: [PATCH] Added point draw method for style 'line' (#2227)

---
 lib/graph3d/Graph3d.js | 102 ++++++++++++++++-------------------------
 1 file changed, 39 insertions(+), 63 deletions(-)

diff --git a/lib/graph3d/Graph3d.js b/lib/graph3d/Graph3d.js
index f84908ef..10e5f5e8 100644
--- a/lib/graph3d/Graph3d.js
+++ b/lib/graph3d/Graph3d.js
@@ -804,6 +804,7 @@ Graph3d.prototype.setOptions = function (options) {
 
   Settings.setOptions(options, this);
 
+  this.setPointDrawingMethod();
   this.setSize(this.width, this.height);
 
   // re-load the data
@@ -819,42 +820,49 @@ Graph3d.prototype.setOptions = function (options) {
 
 
 /**
- * Determine which point drawing method to use
+ * Determine which point drawing method to use for the current graph style.
  */
-Graph3d.prototype.getPointDrawingMethod = function() {
-  var pointDrawingMethod = undefined;
+Graph3d.prototype.setPointDrawingMethod = function() {
+  var method = undefined;
 
   switch (this.style) {
     case Graph3d.STYLE.BAR:
-      pointDrawingMethod = Graph3d.prototype._redrawBarGraphPoint;
+      method = Graph3d.prototype._redrawBarGraphPoint;
       break;
     case Graph3d.STYLE.BARCOLOR:
-      pointDrawingMethod = Graph3d.prototype._redrawBarColorGraphPoint;
+      method = Graph3d.prototype._redrawBarColorGraphPoint;
       break;
     case Graph3d.STYLE.BARSIZE:
-      pointDrawingMethod = Graph3d.prototype._redrawBarSizeGraphPoint;
+      method = Graph3d.prototype._redrawBarSizeGraphPoint;
       break;
     case Graph3d.STYLE.DOT:
-      pointDrawingMethod = Graph3d.prototype._redrawDotGraphPoint;
+      method = Graph3d.prototype._redrawDotGraphPoint;
       break;
     case Graph3d.STYLE.DOTLINE:
-      pointDrawingMethod = Graph3d.prototype._redrawDotLineGraphPoint;
+      method = Graph3d.prototype._redrawDotLineGraphPoint;
       break;
     case Graph3d.STYLE.DOTCOLOR:
-      pointDrawingMethod = Graph3d.prototype._redrawDotColorGraphPoint;
+      method = Graph3d.prototype._redrawDotColorGraphPoint;
       break;
     case Graph3d.STYLE.DOTSIZE:
-      pointDrawingMethod = Graph3d.prototype._redrawDotSizeGraphPoint;
+      method = Graph3d.prototype._redrawDotSizeGraphPoint;
       break;
     case Graph3d.STYLE.SURFACE:
-      pointDrawingMethod = Graph3d.prototype._redrawSurfaceGraphPoint;
+      method = Graph3d.prototype._redrawSurfaceGraphPoint;
       break;
     case Graph3d.STYLE.GRID:
-      pointDrawingMethod = Graph3d.prototype._redrawGridGraphPoint;
+      method = Graph3d.prototype._redrawGridGraphPoint;
+      break;
+    case Graph3d.STYLE.LINE:
+      method = Graph3d.prototype._redrawLineGraphPoint;
+      break;
+    default:
+      throw new Error('Can not determine point drawing method '
+                    + 'for graph style \'' + this.style + '\'');
       break;
   }
 
-  return pointDrawingMethod;
+  this._pointDrawingMethod = method;
 };
 
 
@@ -872,23 +880,7 @@ Graph3d.prototype.redraw = function() {
   this._redrawClear();
   this._redrawAxis();
 
-  var pointDrawingMethod = this.getPointDrawingMethod();
-
-  if (pointDrawingMethod !== undefined) {
-    // Use generic drawing loop
-    // Pass the method reference here
-    this._redrawDataGraph(pointDrawingMethod);
-  } else {
-    // Use the old style drawing methods
-
-    if (this.style === Graph3d.STYLE.LINE) {
-      this._redrawDataLine();
-    }
-    else {
-      // Should not be reached any more.
-      throw new Error('Unknown graph style \'' + this.style + '\'');
-    }
-  }
+  this._redrawDataGraph();
 
   this._redrawInfo();
   this._redrawLegend();
@@ -1810,12 +1802,26 @@ Graph3d.prototype._redrawGridGraphPoint = function(ctx, point) {
 };
 
 
+/**
+ * Draw single datapoint for graph style 'line'.
+ */
+Graph3d.prototype._redrawLineGraphPoint = function(ctx, point) {
+  if (point.pointNext === undefined) {
+    return;
+  }
+
+  ctx.lineWidth   = this._getStrokeWidth(point);
+  ctx.strokeStyle = this.dataColor.stroke;
+
+  this._line(ctx, point.screen, point.pointNext.screen);
+};
+
+
 /**
  * Draw all datapoints for currently selected graph style.
  *
- * @param pointDrawMethod - method reference to draw a point in a specific graph style.
  */
-Graph3d.prototype._redrawDataGraph = function(pointDrawMethod) {
+Graph3d.prototype._redrawDataGraph = function() {
   var ctx = this._getContext();
   var i;
 
@@ -1828,7 +1834,7 @@ Graph3d.prototype._redrawDataGraph = function(pointDrawMethod) {
     var point = this.dataPoints[i];
 
     // Using call() ensures that the correct context is used
-    pointDrawMethod.call(this, ctx, point);
+    this._pointDrawingMethod.call(this, ctx, point);
   }
 };
 
@@ -1838,36 +1844,6 @@ Graph3d.prototype._redrawDataGraph = function(pointDrawMethod) {
 // -----------------------------------------------------------------------------
 
 
-/**
- * Draw a line through all datapoints.
- * This function can be used when the style is 'line'
- */
-Graph3d.prototype._redrawDataLine = function() {
-  var ctx = this._getContext(),
-    point, i;
-
-  if (this.dataPoints === undefined || this.dataPoints.length <= 0)
-    return;  // TODO: throw exception?
-
-  this._calcTranslations(this.dataPoints);
-
-  // start the line
-  if (this.dataPoints.length > 0) {
-    point = this.dataPoints[0];
-
-    ctx.lineWidth = this._getStrokeWidth(point);
-    ctx.strokeStyle = this.dataColor.stroke;
-
-    for (i = 0; i < this.dataPoints.length; i++) {
-      point = this.dataPoints[i];
-
-      if (point.pointNext !== undefined) {
-        this._line(ctx, point.screen, point.pointNext.screen);
-      }
-    }
-  }
-};
-
 /**
  * Start a moving operation inside the provided parent element
  * @param {Event}     event     The event that occurred (required for