attenuation_values

property Light.attenuation_values

Return the quadratic attenuation constants.

The values are 3-length sequences which specify the constant, linear and quadratic constants in this order. These parameters only have an effect for positional lights.

Attenuation refers to the dampening of a beam of light as it gets further away from the point source. The three constants describe three different profiles for dampening with distance. A larger attenuation constant corresponds to more rapid decay with distance.

Examples

Plot three cubes lit by two lights with different attenuation profiles. The blue light has slower linear attenuation, the green one has quadratic attenuation that makes it decay faster. Note that there are no shadow effects included so each box gets lit by both lights.

>>> import pyvista as pv
>>> plotter = pv.Plotter(lighting='none')
>>> for offset in 1, 2.5, 4:
...     _ = plotter.add_mesh(pv.Cube(center=(offset, offset, 0)), color='white')
...
>>> colors = ['b', 'g']
>>> all_attenuations = [(0, 0.1, 0), (0, 0, 0.1)]
>>> centers = [(0, 1, 0), (1, 0, 0)]
>>> for color, attenuation_constants, center in zip(colors, all_attenuations, centers):
...     light = pv.Light(position=center, color=color)
...     light.focal_point = (1 + center[0], 1 + center[1], 0)
...     light.cone_angle = 90
...     light.positional = True
...     light.attenuation_values = attenuation_constants
...     plotter.add_light(light)
...
>>> plotter.view_vector((-1, -1, 1))
>>> plotter.show()
../../../_images/pyvista-Light-attenuation_values-1_00_00.png