Add a line-arc road to a scene, then extract objects for the control points of the
            line-arc road curve.
        Create a roadrunner object,
              specifying the path to an existing project. For example, this code shows the path to a
              project, on a Windows® machine, located at "C:\RR\MyProject". This code
              assumes that RoadRunner is installed in the default location, and returns an object,
                rrApp, that provides functions for performing basic tasks such as
              opening, closing, and saving scenes and projects.
Note
If you are opening RoadRunner from MATLAB® for the first time, or if you have changed the RoadRunner installation location since you last opened it from MATLAB, you can use the roadrunnerSetup function to specify new
                  default project and installation folders to use when opening RoadRunner. You can save these folders between MATLAB sessions by selecting the Across MATLAB
                    sessions option from the corresponding drop down.
Create an object for the RoadRunner authoring API, rrApi, that references the object for the
    current RoadRunner instance rrApp. The rrApi object enables you
    to programmatically author scenes and scenarios, such as by adding and modifying roads, actors,
    and logic components, using MATLAB.
Extract the scene and scenario objects from the 
Scene and
        
Scenario properties of the authoring API object 
rrApi,
    respectively. The extracted 
Scene object enables you to specify the scene in
    which to add scene components such as roads and lanes. The extracted 
Scenario (RoadRunner Scenario) object
    enables you to specify the scenario in which to add scenario components such as actors and
    logic.
Extract the object for your 
RoadRunner project from the 
Project property of the authoring API object
        
rrApi. The extracted 
Project object enables you to
    specify the project folder for the current 
RoadRunner session from which to retrieve asset objects. You can use the asset objects to
    assign assets to roads in your scene, or to actors in your
    scenario.
To create a line-arc road, use the addLineArcRoad
              function and specify the scene in which to add the road and the
                xy-positions of the control points. Then, extract the line-arc
              curve from the HorizontalCurve property of the road
                rrRoad.
Extract LineArcRoadCurvePoint Objects
To extract LineArcRoadCurvePoint objects for the first and
              second control points of the line-arc curve lineArc, specify the
              first and second elements from the ControlPoints property of
                lineArc. 
You can use the LineArcRoadCurvePoint objects to modify the
              properties of the road curve control points. By modifying the control point
              properties, you can change the shape and position of the road in your RoadRunner scene.
To move the road rrRoad in the scene, change the values of the
                Positions properties of the line-arc road curve points
                arcPoint1 and arcPoint2.