Class Light

pvtrace/light/light.py:61–161

Generic light source object which calls delegate functions to help generate rays that sample statistical distributions. Examples -------- Light of 555nm from the origin or the light's node along direction (0, 0, 1):: Light() Light with isotropic direc

class Light(object):
    """ Generic light source object which calls delegate functions to help generate rays that
    sample statistical distributions.
    
    Examples
    --------
    
    Light of 555nm from the origin or the light's node along direction (0, 0, 1)::
    
        Light()
    
    Light with isotropic direction::
        
        from pvtrace.material.utils import isotropic
        Light(direction=isotropic)

    Light emitted within solid-angle of half-angle pi/8 rads::
    
        import functools
        from pvtrace.material.utils import cone
        Light(direction=functools.partial(cone, np.pi/8))

    To generate a Lambertian source::
    
        import functools
        from pvtrace.material.utils import lambertian
        Light(direction=lambertian)
    
    To generate a square spatial distribution in the xy-plane with length and width
    of one unit::
    
        import functools
        Light(position=functools.partial(rectangular_mask, 1, 1)

    To generate a circular spatial distribution in the xy-plane with radius one::
    
        import functools
        Light(position=functools.partial(circular_mask, 1)
    
    Any combination of spatial and divergence delegates can be used to generate the
    required distribution of rays.
    """

    def __init__(self, wavelength=None, position=None, direction=None, name="Light"):
        """
        Returns a light source emitting along the positive z direction of the coordinate system
        the light is attached to. Delegate functions can be used modify the wavelength, position 
        and direction of the emitted ray.

        Parameters
        ----------
        wavelength: callable or None
            A callable which returns the ray's wavelength. The callable should
            have the following signature `func() -> float` which returns the 
            wavelength in nanometers.
        position: callable or None
            A callable which returns the ray's position. The callable should
            have the following signature `func() -> (float, float, float)` which