#lang scribble/manual
@(require (for-label racket))

@title{(decode-b2 numChannels w x y orientation)}


2D Ambisonic B-format decoder.

Decode a two dimensional ambisonic B-format signal to a set of
speakers in a regular polygon.  The outputs will be in clockwise
order. The position of the first speaker is either center or left
of center.

The number of output speakers is typically 4 to 8.

The parameters w, x and y are the B-format signals.

The parameter orientation should be zero if the front is a vertex
of the polygon. The first speaker will be directly in
front. Should be 0.5 if the front bisects a side of the
polygon. Then the first speaker will be the one left of
center. Default is 0.5.


@racketblock[
(let* ((p (pink-noise ar))
       (encoded (pan-b2 p (mouse-x kr -1 1 0 0.1) 0.1))
       (decoded (decode-b2 4
			  (mce-channel encoded 0)
			  (mce-channel encoded 1)
			  (mce-channel encoded 2)
			  0)))
  (audition (out 0 decoded)))
]