The control points of the spline are not set correctly.

1. The control points of the spline are not set correctly: When using a spline, control points need to be set to control the shape and direction of the curve. If the control points are not set correctly, the spline may The line cannot be used.

2. The properties of the spline are incorrectly set: When using the spline, you need to set some properties, such as line width, color, material, etc. If these properties are set incorrectly, it may cause the spline to become unusable.

3. The collision setting of the spline is incorrect: When using the spline, you need to set the collision attribute of the spline for physical simulation and collision detection in the game. If the collision setting is incorrect , which may render the spline unusable.