manual/include/automation-modes.html

<p>
  Ardour offers two modes for interpolating automation control points: <kbd
  class="menu">Linear</kbd> and <kbd class="menu">Discrete</kbd>. The mode is
  changed by a <kbd class="mouse">Right</kbd> click on the automation lane header
  and choosing the mode from the mode menu.
</p>

<figure>
  <img src="/images/automation-linear.png" alt="Automation - linear">
  <img src="/images/automation-discrete.png" alt="Automation - discrete">
  <figcaption>Automation : linear vs discrete.</figcaption>
</figure>

<p>
  <kbd class="menu">Linear</kbd> mode interpolates values between control points
  in a given automation curve by connecting them with straight lines; the values
  played back are derived from the points that lie on the lines thus defined.
  Typically, this is what is desired and is the default mode for all automation
  lanes.
</p>

<p>
  <kbd class="menu">Discrete</kbd> mode does <em>no</em> interpolation between
  control points in a given automation curve. The values set by the control
  points do not change until the following control point is reached at which
  time the value is then set to its value; this continues on until there are no
  more control points. Typically this is used for parameters such as mute or
  sustain pedal (e.g., on a MIDI piano track).
</p>

<p class="note">
  When recording automation via MIDI (e.g., pitch bend from a MIDI keyboard),
  Ardour always uses discrete mode.
</p>