[pitivi] elements: keyframe: Display real value in the tooltip

[Alexandru Băluț <alexbalut src gnome org>]

commit 41626dbf1aad4d5e16449689529c9de64ed687a9
Author: Thibault Saunier <tsaunier gnome org>
Date:   Wed Feb 3 10:11:55 2016 +0100

    elements: keyframe: Display real value in the tooltip
    
    instead of displaying it in a [0-1] scale
    
    Differential Revision: https://phabricator.freedesktop.org/D734

 pitivi/timeline/elements.py |    4 ++++
 1 files changed, 4 insertions(+), 0 deletions(-)
---
diff --git a/pitivi/timeline/elements.py b/pitivi/timeline/elements.py
index 4fd4ce6..63ed010 100644
--- a/pitivi/timeline/elements.py
+++ b/pitivi/timeline/elements.py
@@ -101,6 +101,7 @@ class KeyframeCurve(FigureCanvas, Loggable):
         self.__source.connect("value-removed", self.__controlSourceChangedCb)
         self.__source.connect("value-changed", self.__controlSourceChangedCb)
         self.__propertyName = binding.props.name
+        self.__paramspec = binding.pspec
         self.__resetTooltip()
         self.get_style_context().add_class("KeyframeCurve")
 
@@ -250,6 +251,9 @@ class KeyframeCurve(FigureCanvas, Loggable):
         if event.xdata:
             res, value = self.__source.control_source_get_value(event.xdata)
             assert res
+            pmin = self.__paramspec.minimum
+            pmax = self.__paramspec.maximum
+            value = value * (pmax - pmin) + pmin
             self.set_tooltip_markup(_("Property: %s\nTimestamp: %s\nValue: %s")
                                     % (self.__propertyName,
                                        Gst.TIME_ARGS(event.xdata),