public static void getGeometriesInCamFrustum(Spatial rootScene, Camera camera, RenderQueue.ShadowMode mode, GeometryList outputGeometryList) {
        if (rootScene != null && rootScene instanceof Node) {
            int planeState = camera.getPlaneState();
            addGeometriesInCamFrustumFromNode(camera, (Node)rootScene, mode, outputGeometryList);
            camera.setPlaneState(planeState);
        }
    }
Populates the outputGeometryList with the rootScene children geometries
that are in the frustum of the given camera

@param rootScene the rootNode of the scene to traverse
@param camera the camera to check geometries against
@param mode the ShadowMode to test for
@param outputGeometryList the list of all geometries that are in the
camera frustum
jme3-core/src/main/java/com/jme3/shadow/ShadowUtil.java