From: Evert Timberg <evert.timberg@gmail.com>
Date: Sat, 16 May 2015 23:38:31 +0000 (-0400)
Subject: Some helper functions needed for better scales.
X-Git-Tag: v2.0-alpha~8^2~28
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=b5b00811084e618278550e69e3c247a44163d1fc;p=thirdparty%2FChart.js.git

Some helper functions needed for better scales.
---

diff --git a/src/Chart.Core.js b/src/Chart.Core.js
index 939fecf29..f60d7c2e7 100755
--- a/src/Chart.Core.js
+++ b/src/Chart.Core.js
@@ -360,6 +360,9 @@
         toRadians = helpers.radians = function(degrees) {
             return degrees * (Math.PI / 180);
         },
+		toDegrees = helpers.toDegrees = function(radians) {
+			return radians * (180 / Math.PI);
+		},
         // Gets the angle from vertical upright to the point about a centre.
         getAngleFromPoint = helpers.getAngleFromPoint = function(centrePoint, anglePoint) {
             var distanceFromXCenter = anglePoint.x - centrePoint.x,
@@ -479,6 +482,36 @@
             };
 
         },
+		// Implementation of the nice number algorithm used in determining where axis labels will go
+		niceNum = helpers.niceNum = function(range, round) {
+			var exponent = Math.floor(Math.log10(range));
+			var fraction = range / Math.pow(10, exponent);
+			var niceFraction;
+			
+			if (round) {
+				if (fraction < 1.5) {
+					niceFraction = 1;
+				} else if (fraction < 3) {
+					niceFraction = 2;
+				} else if (fraction < 7) {
+					niceFraction = 5;
+				} else {
+					niceFraction = 10;
+				}
+			} else {
+				if (fraction <= 1.0) {
+					niceFraction = 1;
+				} else if (fraction <= 2) {
+					niceFraction = 2;
+				} else if (fraction <= 5) {
+					niceFraction = 5;
+				} else {
+					niceFraction = 10;
+				}
+			}
+			
+			return niceFraction * Math.pow(10, exponent);
+		},
         /* jshint ignore:start */
         // Blows up jshint errors based on the new Function constructor
         //Templating methods