manual/include/editing-clocks.html

<h2>Clock Modes</h2>

<p>
  Every clock in Ardour has four different, selectable <dfn>clock
  modes</dfn>. Each mode displays time using different units.
  The clock mode can be changed by <kbd class="mouse">Right</kbd>-clicking
  on the clock and selecting the desired mode from the menu. Some clocks are
  entirely independent of any other clock's mode; others are linked so that
  changing one changes all clocks in that group. The different modes are:
</p>

<table class="dl">
  <tr><th>Timecode</th><td>Time is shown as <dfn><abbr title="Society of Motion Picture and Television
  Engineers">SMPTE</abbr> timecode</dfn> in Hours:Minutes:Seconds:Frames,
  measured from the timecode zero point on the timeline (which may not
  correspond to the session start and/or absolute zero on the timeline,
  depending on configurable timecode offsets).
  The frames value is dictated by either the session <abbr title="Frames Per
  Second">FPS</abbr> setting, or, if slaved to an external timecode master,
  the master's setting. In the transport clocks, the FPS value is shown below
  the time display, along with an indication of the current timecode source
  (<samp>INT</samp> means that Ardour is its own timecode source).</td></tr>
  <tr><th>BBT</th><td>Time is shown as Bars:Beats:Ticks, indicating <dfn>musical time</dfn> measured
  from the start of the session. The transport clocks show the current tempo
  in <abbr title="Beats Per Minute">bpm</abbr> and meter below the time
  display.</td></tr>
  <tr><th>Minutes:Seconds</th><td>Time is shown as Hours:Minutes:Seconds.Milliseconds, measured from the
  absolute start of the timeline (ignoring the session start and any timecode
  offsets).</td></tr>
  <tr><th>Samples</th><td>Time is shown as a <dfn>sample count</dfn> from the absolute start of the timeline
  (ignoring the session start and any timecode offsets). The number of
  samples per second is given by the current sample rate, and in the transport
  clocks, this rate is shown below the time display along with any
  pullup/pulldown adjustment.</td></tr>
</table>

<h2>Changing clock values with the keyboard</h2>

<p>
  New values for the clock can be typed in after clicking on the relevant clock.
  Clicking on the clock will show a thin vertical cursor bar just to the right
  of the next character to be overwritten. Time should be typed in the same
  order as the current clock mode&mdash;if the clock is in Timecode mode, it
  should be hours, minutes, seconds, frames. So, to change to a time of
  12:15:20:15 one would type
  <kbd>1</kbd><kbd>2</kbd><kbd>1</kbd><kbd>5</kbd><kbd>2</kbd><kbd>0</kbd><kbd>1</kbd><kbd>5</kbd>.
  Each number typed will appear in a different color, from right to left,
  overwriting the existing value. Mid-edit, after typing <kbd>3</kbd><kbd>2</kbd><kbd>2</kbd><kbd>2</kbd> the clock might look like this:
</p>

<figure>
    <img src="/images/clockedit.png" alt="A clock being edited in Ardour">
    <figcaption>
      A clock being edited in Ardour
    </figcaption>
</figure>

<p>
  Finishing the edit is done by pressing <kbd>&crarr;</kbd> or <kbd>Tab</kbd>.
  The <kbd>ESC</kbd> key allows to exit an edit without changing the clock. If an
  entry is mis-typed  so that the new value would be illegal (for example,
  resulting in more than 30 frames when Timecode is set to 30 frames per second),
  the clock will reset at the end of the edit, and move the cursor back to the
  start to allow for another try.
</p>

<h2>Avoiding the mouse entirely</h2>

<p>
  There is a shortcut available to edit the transport
  clocks entirely without the mouse. It can be found in
  <kbd class="menu">Window &gt; Keyboard Shortcuts &gt; Transport &gt; Focus On
  Clock</kbd>. If bound to a key (<kbd>&divide;</kbd> on the numerical
  keypad is the
  default), then pressing that key is equivalent to clicking on the primary (left)
  transport clock, and editing can begin immediately.
</p>

<h2>Entering Partial Times</h2>

<p>
  One detail of the editing design that is not immediately obvious is that it is
  possible to enter part of a full time value.
</p>
<p>
  As an example, supposing that the clock is in BBT mode, displaying
  <samp>024|03|0029</samp>, altering the value to the first beat of the current
  bar can be done by clicking on the clock and typing
  <kbd>0</kbd><kbd>1</kbd><kbd>0</kbd><kbd>0</kbd><kbd>0</kbd><kbd>0</kbd>.
  Similarly, if it is in Minutes:Seconds mode, displaying
  <samp>02:03:04.456</samp>, getting to exactly 2 hours can be achieved by
  clicking on the clock and typing
  <kbd>0</kbd><kbd>0</kbd><kbd>0</kbd><kbd>0</kbd><kbd>0</kbd><kbd>0</kbd><kbd>0</kbd>
  to reset the minutes, seconds and milliseconds fields.
</p>

<h2>Entering Delta Times</h2>

<p>
  Values can also be typed into the clock that are intended as a relative change,
  rather than a new absolute value, by ending the edit by pressing
  <kbd>+</kbd> or <kbd>-</kbd> (the ones on any keypad will also work). The plus
  key will add the entered value to the current value of the clock, minus will
  subtract it. For example, if the clock is in Samples mode and displays
  <samp>2917839</samp>, moving it back 2000 samples is done by typing
  <kbd>2</kbd><kbd>0</kbd><kbd>0</kbd><kbd>0</kbd> and <kbd>-</kbd>, rather than
  ending with <kbd>Enter</kbd> or <kbd>Tab</kbd>.
</p>

<h2>Changing clock values with the mouse</h2>

<h3>Using a scroll wheel</h3>

<p>
  With the mouse pointer over the clock, moving the scroll wheel changes the
  clock values. Moving the scroll wheel up (<kbd class="mouse">&uArr;</kbd>)
  increases the value shown on the clock, moving it down  (<kbd
  class="mouse">&dArr;</kbd>) decreases it. The step size is equal to the unit
  of the field hovered over (seconds, hours, etc.).
</p>

<h3>Dragging the mouse</h3>

<p>
  With the mouse pointer over the clock, pressing the left mouse button and
  dragging also affects the clocks: dragging upwards increases the value shown
  on the clock, dragging downwards decreases it, again with a step size equal to
  the unit of the field where the drag began on.
</p>