[chronojump] Force sensor capture now time where force starts is always 0

[Xavier de Blas <xaviblas src gnome org>]

commit 18d72c05b6e70cc7c94f412c2d3b12178e2ad4f9
Author: Xavier de Blas <xaviblas gmail com>
Date:   Mon May 8 19:16:45 2017 +0200

    Force sensor capture now time where force starts is always 0

 src/gui/forceSensor.cs |   20 +++++++++++++++++---
 1 files changed, 17 insertions(+), 3 deletions(-)
---
diff --git a/src/gui/forceSensor.cs b/src/gui/forceSensor.cs
index 0519b6d..211bc34 100644
--- a/src/gui/forceSensor.cs
+++ b/src/gui/forceSensor.cs
@@ -104,6 +104,7 @@ public partial class ChronoJumpWindow
                capturingForce = forceStatus.STARTING;
                forceProcessFinish = false;
                forceProcessCancel = false;
+               forceSensorLast = 0;
                
                event_execute_ButtonFinish.Clicked -= new EventHandler(on_finish_clicked);
                event_execute_ButtonFinish.Clicked += new EventHandler(on_finish_clicked);
@@ -121,8 +122,8 @@ public partial class ChronoJumpWindow
        //non GTK on this method
        private void forceSensorCaptureDo()
        {
-               //lastChangedTime = 0;
-               SerialPort port = new SerialPort(forceSensorPortName, 115200);
+               lastChangedTime = 0;
+               SerialPort port = new SerialPort(forceSensorPortName, 115200); //forceSensor
                port.Open();
                Thread.Sleep(2500); //sleep to let arduino start reading
 
@@ -145,12 +146,24 @@ public partial class ChronoJumpWindow
                TextWriter writer = File.CreateText(fileName);
                writer.WriteLine("Time (s);Force(N)");
                str = "";
+               double firstTime = 0;
                while(! forceProcessFinish && ! forceProcessCancel)
                {
                        str = port.ReadLine();
+
                        string [] strFull = str.Split(new char[] {';'});
+                       //LogB.Information("str: " + str);
+
                        //needed to store double in user locale
                        double time = Convert.ToDouble(Util.ChangeDecimalSeparator(strFull[0]));
+
+                       //measurement does not start at 0 time. When we start receiving data, mark this as 
firstTime
+                       if(firstTime == 0)
+                               firstTime = time;
+
+                       //use this to have time starting at 0
+                       time -= firstTime;
+
                        double force = Convert.ToDouble(Util.ChangeDecimalSeparator(strFull[1]));
 
                        writer.WriteLine(time.ToString() + ";" + force.ToString());
@@ -159,6 +172,7 @@ public partial class ChronoJumpWindow
                        //changeSlideIfNeeded(time, force);
                }
                port.WriteLine("Stop");
+
                writer.Flush();
                writer.Close();
                ((IDisposable)writer).Dispose();
@@ -225,7 +239,7 @@ public partial class ChronoJumpWindow
                }
 
                Thread.Sleep (25);
-               LogB.Information(" ForceSensor:"+ forceThread.ThreadState.ToString());
+//             LogB.Information(" ForceSensor:"+ forceThread.ThreadState.ToString());
                return true;
        }