[chronojump] Fixed forceSensor GetForceInPx when max(force) <= 0

[Xavier de Blas <xaviblas src gnome org>]

commit 84ff61854bca871896955ff8c406221348038d00
Author: Xavier de Blas <xaviblas gmail com>
Date:   Mon Oct 30 13:21:33 2017 +0100

    Fixed forceSensor GetForceInPx when max(force) <= 0

 src/forceSensor.cs |    6 ++++--
 src/util.cs        |    9 +++++++++
 2 files changed, 13 insertions(+), 2 deletions(-)
---
diff --git a/src/forceSensor.cs b/src/forceSensor.cs
index db13bb9..ec91459 100644
--- a/src/forceSensor.cs
+++ b/src/forceSensor.cs
@@ -75,8 +75,10 @@ public class ForceSensorCapturePoints
 
        public int GetForceInPx(double force)
        {
-               return Convert.ToInt32( (heightG/2) - ( force * heightG / RealHeightG) );
-               //return Convert.ToInt32( heightG - ( force * heightG / RealHeightG) -100 );
+               return Convert.ToInt32(
+                               (heightG/2)
+                               - ( Util.DivideSafe((force * heightG), (1.0 * RealHeightG)) )
+                               );
        }
 
        private Gdk.Point getLastPoint()
diff --git a/src/util.cs b/src/util.cs
index 30545cd..b1ad7d7 100644
--- a/src/util.cs
+++ b/src/util.cs
@@ -1793,6 +1793,15 @@ public class Util
                return DivideSafeFraction(Convert.ToDouble(val1), Convert.ToDouble(val2));
        }
 
+       //Not restricted to values 0-1
+       public static double DivideSafe (double val1, double val2)
+       {
+               if(val1 == 0 || val2 == 0)
+                       return 0;
+
+               return val1 / val2;
+       }
+
        /*
        //converts all values to positive
        public static string StringValuesAbsolute (string myString) {