seam.basic.lib

SEAM Basics library. Its official prefix is sba.

Reusable low-level building blocks that EXTEND the standard Faust basics.lib: only elements not already provided upstream are kept here.

References

Sweep Functions

Ramp/counter generators used across SEAM instruments.

(sba.)sweep

Repeating sample counter. Differs from ba.sweep: it counts from 0 to (p*t)-1 (via the 1' seed) rather than starting at 1, and uses p*t as the period.

Usage

sweep(p,t) : _

Where:

  • p: base period in samples
  • t: period multiplier (final period is p*t)

Test

sba = library("seam.basic.lib");
sweep_test = sba.sweep(1,10);

(sba.)lsweep

Linear sweep from 0 up to Nyquist (ma.SR/2), repeating every sec seconds.

Usage

lsweep(sec,t) : _

Where:

  • sec: sweep duration in seconds
  • t: period multiplier

Test

sba = library("seam.basic.lib");
lsweep_test = sba.lsweep(0.01,1);

(sba.)zsweep

Zero-padded sweep: a sweep of length p preceded by p samples of zero, yielding a 2p+1 frame useful for zero-padded spectral analysis.

Usage

zsweep(p) : _

Where:

  • p: sweep length in samples

Test

sba = library("seam.basic.lib");
zsweep_test = sba.zsweep(10);

(sba.)zerox

One-sample pulse on a rising zero crossing (negative -> non-negative). A directional variant of ma.zc, which fires on any crossing.

Usage

_ : zerox : _

Where the input is any signal; output is 1 for one sample at each upward zero crossing, 0 otherwise.

Test

os = library("oscillators.lib");
sba = library("seam.basic.lib");
zerox_test = os.osc(1000) : sba.zerox;

List Functions

(sba.)revlist

Parallel bus of n constants counting DOWN: n, n-1, ... , 1.

Usage

revlist(n)

Where:

  • n: number of parallel outputs (compile-time constant)

Test

sba = library("seam.basic.lib");
revlist_test = sba.revlist(23);

Scaling

(sba.)scalel

Linear (affine) rescale of x from input range [a,b] to output range [c,d].

Usage

_ : scalel(a,b,c,d) : _

Where:

  • a, b: input range (min, max)
  • c, d: output range (min, max)

Test

os = library("oscillators.lib");
sba = library("seam.basic.lib");
scalel_test = os.osc(1000) : sba.scalel(-1,1,0,1);

Routing

(sba.)vstin

Input manager: pass the first y channels through, block the next n.

Usage

si.bus(y+n) : vstin(y,n) : si.bus(y)

Where:

  • y: number of channels to pass
  • n: number of channels to block

Test

sba = library("seam.basic.lib");
vstin_test = sba.vstin(1,3);