el.sampleseq(props, t)

The sampleseq node is similar in spirit to the sparseq2, but for sequencing sample playback over time.

To see why this is helpful, let's consider that we can already sequence sample playback using el.sample if we build a sequence of triggers using sparseq2:

let seq = el.sparseq2({
  seq: [
    { time: 0.0, value: 1 },
    { time: 0.5, value: 0 },
    { time: 1.0, value: 1 },
    { time: 1.5, value: 0 },
  ]
}, el.div(el.time(), el.sr()));
 
let sequencedSample = el.sample({path}, seq, 1);

This example works great when time moves forward consistently, but breaks down if our time signal were to jump around (i.e. in the case of running against a timeline where the user has control to move the playhead). In our example code here, if time suddenly jumped from 0.4s to 0.0s, the sparseq2 node would not change its output because at both of these points in time it should emit 1. But el.sample does not know to retrigger if it has not received a 0 (it only triggers on the rising edge of an incoming pulse signal).

Here is exactly where sampleseq plays a role. Using sampleseq we can effectively merge the above example into one node, so that if our input time does jump around, we can effectively reposition the playhead within the sample buffer that we're playing.

let sequencedSample = el.sampleseq({
  seq: [
    { time: 0.0, value: 1 },
    { time: 0.5, value: 0 },
    { time: 1.0, value: 1 },
    { time: 1.5, value: 0 },
  ],
  path,
  duration: 4,
}, el.div(el.time(), el.sr()));

So sampleseq expects a sparsely defined sequence given as an array of { time, value } pairs as the seq prop, and a single input signal giving the current time value. The specific units of time are at your discretion, but you should be sure that the values given in the seq prop are in the same units as the input signal. Similar to the idea of el.sample, a value of 1 in the sequence of values represents triggering the sample, and a value of 0 represents muting the sample.

sampleseq also expects a path prop equivalent to that of el.sample, as well as a duration prop which represents the sample's duration in the same units as the input time signal.

Props