HoaYPR | SuperCollider 3.13.0 Help

Description

Rotate a Higher Order Ambisonic signal (HOA) around the z, y' and x" axes.

Compound rotations: yaw, pitch, roll.

NOTE: Mixed intrinsic (z-axis), extrinsic (y' & x"-axes) rotations. This rotation differs from HoaRTT, which is extrinsic.

Class Methods

.ar

Arguments:

in	The input signal.
yaw	Rotation angle around z-axis, in radians.
pitch	Rotation angle around y'-axis, in radians.
roll	Rotation angle around x"-axis, in radians.
order	Ambisonic order.

Discussion:

Transform is equivalent to extrinsic rotations HoaRoll followed by HoaPitch and then HoaYaw.

Examples

Rotate around z, y' and x" axes

// Inspect the ATK's speed of sound reference
"Speed of sound: % m/s".format(AtkHoa.speedOfSound);

// Inspect the ATK's reference radius
"Reference radius: % m".format(AtkHoa.refRadius);

// Inspect the ATK's channel/coefficient ordering
"Coefficient ordering: %".format(AtkHoa.ordering);

// Inspect the ATK's channel/coefficient ordering
"Coefficient normalisation: %".format(AtkHoa.normalisation);

// simple test...

// boot rt server
s.boot;

// choose Ambisonic order
~order = 1
~order = 2
~order = 3

// choose an outbus, if need be
~outbus = 0

// open scope
s.scope(~order.asHoaOrder.size, ~outbus);

// audition
(
{
    // saw params
    var freq = 110.0;
    var gain = -12;

// azimuth & elevation
    var theta = 0.0;
    var phi = 0.0;
    var rotateRate = 0.25;

// radius
    // var radius = 1.0;  // inside reference radius
    var radius = 1.5;  // at reference radius
    // var radius = 2.0;  // beyond reference radius

// signals
    var sig;
    var sigHoa;
    var sigHoaRot;
    var ypr;

sig = Saw.ar(freq, gain.dbamp);

ypr = LFSaw.kr(LFNoise2.kr(1.dup(3)).range(0.75 * rotateRate, 1.25 * rotateRate), mul: pi);

// encode
    sigHoa = HoaEncodeDirection.ar(sig, theta, phi, radius, ~order);

// rotate
    sigHoaRot = HoaYPR.ar(
        sigHoa,
        ypr[0],
        ypr[1],
        ypr[2],
        ~order
    );

// out
    sigHoaRot
}.play(outbus: ~outbus)
)

// quit rt server
s.quit

helpfile source: HelpSource/Classes/HoaYPR.schelp
link::atk-sc3/Classes/HoaYPR::

HoaYPRExtension