makeGizmos method

void makeGizmos(dynamic tbCenter, dynamic tbRadius)

• Creates the rotation gizmos matching trackball center and radius
• tbCenter The trackball center
• tbRadius The trackball radius

Implementation

void makeGizmos(tbCenter, tbRadius) {
    final curve = EllipseCurve(0, 0, tbRadius, tbRadius);
    final points = curve.getPoints(_curvePts);

    //geometry
    final curveGeometry = BufferGeometry().setFromPoints(points);

    //material
    final curveMaterialX = LineBasicMaterial.fromMap({'color': 0xff8080, 'fog': false, 'transparent': true, 'opacity': 0.6});
    final curveMaterialY = LineBasicMaterial.fromMap({'color': 0x80ff80, 'fog': false, 'transparent': true, 'opacity': 0.6});
    final curveMaterialZ = LineBasicMaterial.fromMap({'color': 0x8080ff, 'fog': false, 'transparent': true, 'opacity': 0.6});

    //line
    final gizmoX = Line(curveGeometry, curveMaterialX);
    final gizmoY = Line(curveGeometry, curveMaterialY);
    final gizmoZ = Line(curveGeometry, curveMaterialZ);

    const rotation = math.pi * 0.5;
    gizmoX.rotation.x = rotation;
    gizmoY.rotation.y = rotation;

    //setting state
    _gizmoMatrixState0.identity().setPosition(tbCenter.x, tbCenter.y, tbCenter.z);
    _gizmoMatrixState.setFrom(_gizmoMatrixState0);

    if (camera.zoom != 1) {
      //adapt gizmos size to camera zoom
      final size = 1 / camera.zoom;
      _scaleMatrix.makeScale(size, size, size);
      _translationMatrix.makeTranslation(-tbCenter.x, -tbCenter.y, -tbCenter.z);

      _gizmoMatrixState.premultiply(_translationMatrix).premultiply(_scaleMatrix);
      _translationMatrix.makeTranslation(tbCenter.x, tbCenter.y, tbCenter.z);
      _gizmoMatrixState.premultiply(_translationMatrix);
    }

    _gizmoMatrixState.decompose(
        _gizmos.position, _gizmos.quaternion, _gizmos.scale);

    _gizmos.clear();

    _gizmos.add(gizmoX);
    _gizmos.add(gizmoY);
    _gizmos.add(gizmoZ);
  }