def __node(self): # this function creates and returns particles' GeomNode points = GeomPoints(GeomEnums.UH_static) points.addNextVertices(self.__numPart) format_ = GeomVertexFormat.getEmpty() geom = Geom(GeomVertexData("abc", format_, GeomEnums.UH_static)) geom.addPrimitive(points) geom.setBounds(OmniBoundingVolume()) # always render it node = GeomNode("node") node.addGeom(geom) return node