<!DOCTYPE html>
<html>
<meta http-equiv="Content-Type" content="text/html;charset=UTF-8" >
<title> Rework the GStreamer Editing Services class hierarchy </title>
<xmp theme="cerulean" style="display:none;">

Reasoning:
----------

All the time (position) related concepts are shared between GESTimelineObject and GESTrackObject
and currently are repeated at the 2 levels.
Moreover, if we want to add the concept of Group we end up with something quite similare to the current
GESTimelineObject but that contains GESTimelineObject-s instead of GESTrackObject-s so we could share
those informations creating a new class aiming at containing the objects that have that
notion of timing.

At the same time, we want to clarify namings. First we should remove the word Object in class names,
we have been told various times that it sounds just "wrong" for people as Objects are instances and there
we are talking about Classes.

Class Hierarchy:
-------------

<pre><code>
<table>
<tr>
  <td>

Before:
-------

GESTimelineObject
    GESTimelineSource
        GESCustomTimelineSource
        GESTimelineTestSource
        GESTimelineFileSource
        GESTimelineTitleSource
    GESTimelineOperation
        GESTimelineOverlay
            GESTimelineTextOverlay
        GESTimelineTransition
            GESTimelineTransition
        GESTimelineEffect
            GESTimelineParseLaunchEffect
GESTimelineLayer
    GESSimpleTimelineLayer
GESTrackObject
    GESTrackSource
        GESTrackAudioTestSource
        GESTrackFileSource
        GESTrackImageSource
        GESTrackTitleSource
        GESTrackVideoTestSource
    GESTrackOperation
        GESTrackTransition
            GESTrackAudioTransition
            GESTrackVideoTransition
        GESTrackEffect
            GESTrackParseLaunchEffect
        GESTrackTextOverlay
  </td>
  <td>

After:
-------

GESTimelineElement
    GESContainer
        GESClip
            GESSourceClip
                GESCustomSourceClip
                GESTestClip
                GESUriClip
                GESTitleClip
            GESOperationClip
                GESOverlayClip
                    GESTextOverlayClip
                GESBaseTransitionClip
                    GESTransitionClip
                GESBaseEffectClip
                    GESEffectClip
        GESClipGroup
    GESTrackElement
        GESSource
            GESAudioTestSource
            GESUriSource
            GESImageSource
            GESTitleSource
            GESVideoTestSource
        GESOperation
            GESTransition
                GESAudioTransition
                GESVideoTransition
            GESBaseEffect
                GESEffect
            GESTextOverlay
    </td>
  </tr>
</table>
</code></pre>
</xmp>
<script src="http://strapdownjs.com/v/0.1/strapdown.js"></script>
</html>

Add an little explanation about the class hierarchie rework
docs: Add an little explanation about the class hierarchie rework
