adsk-forge-LevelSectionPanel-step13

getCutPlaneParam( idx, n ) {
    if( idx < 0 || !n ) return;

    const level = this.levels[idx];

    if( !level ) return;

    const model = this.viewer.model;

    const globalOffset = model.getData().globalOffset;
    const units = model.getUnitString();
    const elevRaw = Autodesk.Viewing.Private.convertUnits( level.units, units, 1, level.elevation );

    let d = elevRaw - globalOffset.z;

    if( n == 1 )
        d = -1 * d;

     return new THREE.Vector4( 0, 0, n, d );
}