VBAP Ugens 3D config, azimuth = -90 and spread = 1 causes NANs

[miguel-negrao]

a = VBAPSpeakerArray.new(3, [
                    [ -25.400967366, 0 ],
                    [ 25.9660516833, 0 ],
                    [ -67.0576274588, 0 ],
                    [ 66.6879780945, 0 ],
                    [ -107.4110491464, 0 ],
                    [ 107.3832377266, 0 ],
                    [ -146.2172414806, 0 ],
                    [ 146.1054525865, 0 ],
                    [ -20.4495476108, 17.8750032812 ],
                    [ 20.571247071, 17.8150833255 ],
                    [ -65.6744247609, 24.0287030727 ],
                    [ 65.6416496995, 23.9189613576 ],
                    [ -108.1204280324, 24.7878302634 ],
                    [ 108.1462414292, 24.906009848 ],
                    [ -155.454155974, 23.6313179834 ],
                    [ 155.6036500106, 23.5605201117 ],
                    [ -27.5218854663, 52.7448792263 ],
                    [ 28.2311587404, 52.8541958285 ],
                    [ -74.594892688, 57.9362142825 ],
                    [ 73.451059145, 59.0965878748 ],
                    [ -113.1577815608, 57.1078901345 ],
                    [ 110.9030667368, 56.4426902381 ],
                    [ -151.3671810066, 54.2142657891 ],
                    [ 152.046597927, 52.8541958285 ],
                    [ -28.0372821602, -50.4062940572 ],
                    [ 28.0372821602, -50.4062940572 ],
                    [ -77.6309384741, -52.9029151782 ],
                    [ 77.1957339347, -53.8362268718 ],
                    [ -116.4957697362, -51.38202567 ],
                    [ 116.7749248886, -51.6531568981 ],
                    [ -159.9660768355, -50.2322714936 ],
                    [ 157.4926118991, -49.7580403359 ]
                ]); // zig zag partial dome

b = Buffer.sendCollection(s, a.getSetsAndMatrices);

(
// pan around the circle up and down
x = {
var source;
source = PinkNoise.ar(0.2);
VBAP.ar(32, source, b.bufnum, -90, 0, 1);
}.play;
)

trace on they synth:

unit 45 VBAP
in 0.0105448 0 -90 0 1
out nan nan nan nan nan nan nan nan nan nan nan nan nan nan nan nan nan nan nan nan nan nan nan nan nan nan nan nan nan nan nan nan

[blazpavlica]

This issue still exists. It only happens when elevation is 0 and azimuth is set to -90. Spread doesn't seem to matter for this error. Weirdly if you set the elevation to something not 0 and back to 0, it wont't happen. Here is a minimum code to reproduce:

(// evaluate this after booting
~directions= [
	[ 36.000002344437, -22.810909368454 ],
	[ 107.99997338035, -22.810900790441 ],
	[ -180.0, -22.810897559984 ],
	[ -107.99997338035, -22.810900790441 ],
	[ -36.000002344437, -22.810909368454 ],
	[ 0.0, 8.4078204108839 ],
	[ 71.999976488379, 8.4078411022254 ],
	[ 144.00004116466, 8.4078238253143 ],
	[ -144.00004116466, 8.4078238253143 ],
	[ -71.999976488379, 8.4078411022254 ],
	[ -36.000072811892, 40.60295346006 ],
	[ 36.000072811892, 40.60295346006 ],
	[ 90.0, 90.0 ],
	[ -180.0, 40.602838319582 ]
];
~vbapArray = VBAPSpeakerArray.new(3,~directions);
~vbapBuf = ~vbapArray.loadToBuffer;
~defineObjekt = { arg name;
	SynthDef(name, { arg azimuth=0, elevation=0,spread=72; // initial elevation has to be 0 for the error to happen
		var sig = VBAP.ar(
			~directions.size,
			SinOsc.ar(200)*0.05,
			~vbapBuf.bufnum,
			azimuth,
			elevation,
			spread
		);
		Out.ar(0,sig)
	}).send(s);
};
)

~defineObjekt.("obj1"); // define SytnhDef
~synth = Synth("obj1"); // add synth

~synth.set("azimuth",-90); // when this is set VBAP outputs -nan

~synth.set("elevation",1); // if you first change elevation to something else and back to 0,
~synth.set("elevation",0);
~synth.set("azimuth",-90); // then this will work

My quick fix is to start with elevation at 0.001.