protected void createShape() {
        cShape = new StaticPlaneShape(Converter.convert(plane.getNormal()),plane.getConstant());
        cShape.setLocalScaling(Converter.convert(getScale()));
        cShape.setMargin(margin);
    }
Creates a plane Collision shape
@param plane the plane that defines the shape
jme3-jbullet/src/main/java/com/jme3/bullet/collision/shapes/PlaneCollisionShape.java