manual/include/ruler.html

<figure>
    <img src="/images/ruler.png" alt="Ardour's Ruler">
    <figcaption>
      Ardour's Ruler
    </figcaption>
</figure>


<p>
  The <dfn>ruler</dfn> scales the session along time, allows navigating, and
  can be marked for different uses.
</p>
<p>
  One of its main uses is to move the playhead: clicking anywhere on the
  timeline will bring the playhead at this location in time. Also, using the
  mouse's scrollwheel while hovering the ruler will zoom in or out
  (<kbd class="mouse">&uArr;</kbd>/<kbd class="mouse">&dArr;</kbd> ).
</p>
<p>
  The ruler is made of a succession of rows, each having a special role related
  to time. Adding or removing rows can be done by <kbd class="mouse">right</kbd>
  clicking anywhere in the ruler's header on the left, and ticking any of:
</p>

<table class="dl">
  <tr>
    <th><dfn>Mins:Secs</dfn></th>
    <td>scaling the session with the Mins:Secs:mSec notation</td>
  </tr>
  <tr>
    <th><dfn>Timecode</dfn></th>
    <td>scaling the session with the Hours:Mins:Secs:Frames notation</td>
  </tr>
  <tr>
    <th><dfn>Samples</dfn></th>
    <td>scaling the session with the sample number notation</td>
  </tr>
  <tr>
    <th><dfn>Bars:Beats</dfn></th>
    <td>slicing the time according to the time signature</td>
  </tr>
	<tr>
    <th><dfn>Time Signature</dfb></th>
    <td>shows the time signature. It can be changed along the timeline, by
    <kbd class="mouse">Right-click</kbd> &gt;
    <kbd class="menu">New Time Signature</kbd>. The Bars:Beats ruler will
    reflect the change.</td>
  </tr>
	<tr>
    <th><dfn>Tempo</dfn></th>
    <td>shows the BPM. It can be changed along the timeline, by
    <kbd class="mouse">Right-click</kbd> &gt; <kbd class="menu">New Tempo</kbd>.
    The Bars:Beats ruler will reflect the change.</td>
  </tr>
	<tr>
    <th><dfn>Range Markers</dfn></th>
    <td>allow to create and modify ranges directly on the Ruler.</td>
  </tr>
	<tr>
    <th><dfn>Loop/Punch Ranges</dfn></th>
    <td>are special kind of ranges designed to be played as a loop and to do
    punch recording, i.e. recording on a precise section of time, respectively.</td>
  </tr>
	<tr>
    <th><dfn>CD Markers</dfn></th>
    <td>are markers designed to be used while creating a recording that has
    to be split in time, as an audio CD</td>
  </tr>
  <tr>
    <th><dfn>Location Markers</dfn></th>
    <td>is meant to receive any kind of marker, user generated or from Ardour
    itself.</td>
  </tr>
  <tr>
    <th><dfn>Cue Markers</dfn></th>
    <td>allows triggering entire cues from the grid in the <em>Cue</em>window</td>
  </tr>
  <tr>
    <th><dfn>Video Timeline</dfn></th>
    <td>shows thumbnails of the <a href="@@video-timeline-and-monitoring">video</a>
    in the timeline</td>
  </tr>
</table>

<p>
  Most rulers allow placing markers to serve a specific purpose: mark a point in
  time, define a loop range, or something else entirely.
</p>

<p>
  Most of the operations on the markers are described in <a
  href="@@working-with-markers">Working with Markers</a>, additional information
  on Time Signature, Tempo, Bars:Beats, and Timecode is available in the
  <a href="@@tempo-and-meter">Tempo and Time Signature</a> chapter.
</p>