Class Ray

pvtrace/light/ray.py:12–84

A ray of light. Has the physical attributes of position, direction and wavelength. Attributes ---------- position : tuple of float The (x, y, z) position. direction : tuple of floats Direction unit vector (n_i, n_j, n_k). wavelength : float The

@dataclass(frozen=True)
class Ray:
    """ A ray of light. Has the physical attributes of position, direction and 
    wavelength.
    
    Attributes
    ----------
    position : tuple of float
        The (x, y, z) position.
    direction : tuple of floats
        Direction unit vector (n_i, n_j, n_k).
    wavelength : float
        The wavelength in nanometers.
    is_alive : bool
        Indicates if the ray is not dead
    travelled : float
        Total propagation distance. This gets updated when when calling `propagate`.
    source: float
        Identifier of the light source of luminophore that emitted the ray.
    """

    position: tuple
    direction: tuple
    wavelength: Optional[float]
    is_alive: bool = True
    travelled: float = 0.0
    source: Optional[str] = None

    def __repr__(self):
        position = "(" + ", ".join(["{:.2f}".format(x) for x in self.position]) + ")"
        direction = "(" + ", ".join(["{:.2f}".format(x) for x in self.direction]) + ")"
        wavelength = "{:.2f}".format(self.wavelength)
        is_alive = "True" if self.is_alive else "False"
        args = (position, direction, wavelength, is_alive)
        return "Ray(pos={}, dir={}, nm={}, alive={})".format(*args)

    def propagate(self, distance: float) -> Ray:
        """ Returns a new ray which has been moved the specified distance along
        its direction.
        
        Parameters
        ----------
        distance : float
            The distance to move the ray. Can be negative in which case the new
        ray will be moved backwards.
        """
        if not self.is_alive:
            raise ValueError("Ray is not alive.")
        new_position = np.array(self.position) + np.array(self.direction) * distance
        new_position = tuple(new_position.tolist())
        new_ray = replace(
            self, position=new_position, travelled=self.travelled + distance
        )
        return new_ray

    def representation(self, from_node: Node, to_node: Node) -> Ray:
        """ Representation of the ray in another coordinate system.
        
        Parameters