stroke.cs

// Untested Tilt Brush script
// Try running this in a tool script.
// Gleaned from ParametricStrokeCreator.cs and PointerManager.cs

var xfPointer_CS = App.Scene.ActiveCanvas.AsCanvas[rAttachPoint];
ParametricStrokeCreator currentCreator = new CircleCreator(xfPointer_CS);
PointerScript script = PointerManager.m_Instance.MainPointer;
script.CreateNewLine(
    App.Scene.ActiveCanvas,
    xfPointer_CS,
    currentCreator
);
script.SetControlPoint(xfPointer_CS, isKeeper: true);