New failure case

[gkjohnson]

const w = 0.45;
const h = 0.45;
const l = 0.45;
const e = ( w + h + l ) / 30;

const b1 = new Brush( new SphereGeometry( 1, 17, 5 ) );
b1.scale.set( l - e, h - e, w + 1e-4 );
b1.updateMatrixWorld();

const b2 = new Brush( b1.geometry );
b2.scale.set( l + 1e-4, h - e, w - e );
b2.updateMatrixWorld();

const evaluator = new Evaluator();
evaluator.debug.enabled = true;

const result = evaluator.evaluate( b1, b2, ADDITION );

[gkjohnson]

Triangle 117 has the issue:

And is partially inverted:

It looks like the only intersection point is at one vertex: