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Visualization

gradysim.simulator.handler.visualization

This handler adds visualization to the simulation. It shows regularly updated node positions in a graphical representation of the simulation. This graphical representation is web-based and can be accessed via a browser through this link. When the simulation starts running a WebSocket server is started which the browser connects to. The browser then displays the simulation in a 3D environment. The visualization is updated regularly with the current node positions and other information.

Danger

The visualization handler uses a separate process to run the WebSocket server, this means that on Windows your script will be rerun when the new process starts. This means that any code that should not be run multiple times should be put in the if __name__ == "__main__" block.

VisualizationConfiguration dataclass

Configuration for the VisualizationHandler

Source code in gradysim/simulator/handler/visualization.py 
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@dataclass
class VisualizationConfiguration:
    """
    Configuration for the VisualizationHandler
    """

    information_collection_interval: float = 0.01
    """
    Interval in simulation seconds between visualization information update. Beware that this is not the frequency
    at which the visualization is updated in the browser, but the frequency at which data is collected from the 
    running simulation. You can change the broser update frequency with the `update_rate` parameter.
    """

    update_rate: float = 0.05
    """
    Rate in seconds at which the visualization is updated in the browser. This is the frequency at which the browser
    receives the information from the simulation.
    """

    x_range: Tuple[float, float] = (-50, 50)
    """Range of the X axis of the visualization in meters"""

    y_range: Tuple[float, float] = (-50, 50)
    """Range of the Y axis of the visualization in meters"""

    z_range: Tuple[float, float] = (0, 50)
    """Range of the Z axis of the visualization in meters"""

    host: str = "localhost"
    """Host address of the visualization server"""

    port: int = 5678
    """Port that the visualization server will run in"""

    open_browser: bool = False
    """Whether to open the browser automatically when the simulation starts"""

host: str = 'localhost' class-attribute instance-attribute

Host address of the visualization server

information_collection_interval: float = 0.01 class-attribute instance-attribute

Interval in simulation seconds between visualization information update. Beware that this is not the frequency at which the visualization is updated in the browser, but the frequency at which data is collected from the running simulation. You can change the broser update frequency with the update_rate parameter.

open_browser: bool = False class-attribute instance-attribute

Whether to open the browser automatically when the simulation starts

port: int = 5678 class-attribute instance-attribute

Port that the visualization server will run in

update_rate: float = 0.05 class-attribute instance-attribute

Rate in seconds at which the visualization is updated in the browser. This is the frequency at which the browser receives the information from the simulation.

x_range: Tuple[float, float] = (-50, 50) class-attribute instance-attribute

Range of the X axis of the visualization in meters

y_range: Tuple[float, float] = (-50, 50) class-attribute instance-attribute

Range of the Y axis of the visualization in meters

z_range: Tuple[float, float] = (0, 50) class-attribute instance-attribute

Range of the Z axis of the visualization in meters

VisualizationHandler

Bases: INodeHandler

Adds visualization to the simulation. Shows regularly updated node position and other simulation information in a graphical representation of the simulation. The graphical representation is web-based and can be accessed via a browser through this link.

The visualization handler uses a separate process to run the WebSocket server, on Windows your script will be rerun when the new process starts. This means that any code that should not be run multiple times should be put in the if __name__ == "__main__" block.

Source code in gradysim/simulator/handler/visualization.py 
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class VisualizationHandler(INodeHandler):
    """
    Adds visualization to the simulation. Shows regularly updated node position and other simulation information
    in a graphical representation of the simulation. The graphical representation is web-based and can be accessed
    via a browser through [this link](https://project-gradys.github.io/gradys-sim-nextgen-visualization/).

    The visualization handler uses a separate process to run the WebSocket server, on Windows your
    script will be rerun when the new process starts. This means that any code that should not be run multiple times
    should be put in the `if __name__ == "__main__"` block.
    """
    _event_loop: EventLoop
    _nodes: List[Node]
    _information: _VisualizationInformation
    _visualization_state: _VisualizationState
    _information_thread: multiprocessing.Process
    _start_time: float
    command_queue: multiprocessing.Queue

    def __init__(self, configuration: VisualizationConfiguration = VisualizationConfiguration()):
        """
        Constructs the visualization handler.

        Args:
            configuration: Configuration for the visualization handler. If not set all default values will be used.
        """
        self._nodes = []

        # Current simulation information shared with the visualization server
        manager = multiprocessing.Manager()
        self._information = manager.dict()
        self._visualization_state = manager.dict()
        self.command_queue = manager.Queue()
        self._visualization_state["paused"] = False

        self._configuration = configuration

        self._logger = logging.getLogger()

        global _active_handler
        _active_handler = self

    @staticmethod
    def get_label() -> str:
        return "visualization"

    def inject(self, event_loop: EventLoop) -> None:
        self._event_loop = event_loop

        self._event_loop.schedule_event(self._event_loop.current_time + self._configuration.information_collection_interval,
                                        self._report_information,
                                        "Visualization")

    def initialize(self) -> None:
        initialization_information = {
            "x_range": self._configuration.x_range,
            "y_range": self._configuration.y_range,
            "z_range": self._configuration.z_range,
            "nodes": [label_node(node) for node in self._nodes],
        }

        # Initialize with precise CPU timestamp of simulation's start
        # does not use event loop
        self._start_time = time.time()

        self._information_thread = multiprocessing.Process(target=_visualization_thread,
                                                           args=(self._configuration,
                                                                 initialization_information,
                                                                 self._information,
                                                                 self._visualization_state,
                                                                 self.command_queue))
        self._information_thread.start()

    def finalize(self) -> None:
        self._information_thread.terminate()

    def register_node(self, node: Node) -> None:
        self._nodes.append(node)

    def _report_information(self) -> None:
        self._information["nodes"] = [node.id for node in self._nodes]
        self._information["positions"] = [node.position for node in self._nodes]
        self._information["simulation_time"] = self._event_loop.current_time
        self._information["real_time"] = time.time() - self._start_time
        self._information["tracked_variables"] = \
            [node.protocol_encapsulator.protocol.provider.tracked_variables.copy() for node in self._nodes]

        if self._visualization_state["paused"]:
            logging.info("Visualization paused by user")

            while self._visualization_state["paused"]:
                time.sleep(0.1)

            logging.info("Visualization resumed by user")

        self._event_loop.schedule_event(
            self._event_loop.current_time + self._configuration.information_collection_interval,
            self._report_information,
            "Visualization"
        )

__init__(configuration=VisualizationConfiguration())

Constructs the visualization handler.

Parameters:

Name Type Description Default
configuration VisualizationConfiguration

Configuration for the visualization handler. If not set all default values will be used.

 VisualizationConfiguration()
Source code in gradysim/simulator/handler/visualization.py 
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def __init__(self, configuration: VisualizationConfiguration = VisualizationConfiguration()):
    """
    Constructs the visualization handler.

    Args:
        configuration: Configuration for the visualization handler. If not set all default values will be used.
    """
    self._nodes = []

    # Current simulation information shared with the visualization server
    manager = multiprocessing.Manager()
    self._information = manager.dict()
    self._visualization_state = manager.dict()
    self.command_queue = manager.Queue()
    self._visualization_state["paused"] = False

    self._configuration = configuration

    self._logger = logging.getLogger()

    global _active_handler
    _active_handler = self