# -*- coding: utf-8 -*-
"""
Optical Phenomenon Plotting
===========================
Defines the optical phenomena plotting objects:
- :func:`colour.plotting.single_rayleigh_scattering_spd_plot`
- :func:`colour.plotting.the_blue_sky_plot`
"""
from __future__ import division
import matplotlib.pyplot
from colour.colorimetry import spectral_to_XYZ
from colour.models import XYZ_to_sRGB
from colour.phenomena import rayleigh_scattering_spd
from colour.phenomena.rayleigh import (
AVERAGE_PRESSURE_MEAN_SEA_LEVEL, DEFAULT_ALTITUDE, DEFAULT_LATITUDE,
STANDARD_AIR_TEMPERATURE, STANDARD_CO2_CONCENTRATION)
from colour.plotting import (ASTM_G_173_ETR, ColourSwatch, canvas, get_cmfs,
render, single_colour_swatch_plot,
single_spd_plot)
from colour.utilities import normalise_maximum
__author__ = 'Colour Developers'
__copyright__ = 'Copyright (C) 2013-2018 - Colour Developers'
__license__ = 'New BSD License - http://opensource.org/licenses/BSD-3-Clause'
__maintainer__ = 'Colour Developers'
__email__ = 'colour-science@googlegroups.com'
__status__ = 'Production'
__all__ = ['single_rayleigh_scattering_spd_plot', 'the_blue_sky_plot']
[docs]def single_rayleigh_scattering_spd_plot(
CO2_concentration=STANDARD_CO2_CONCENTRATION,
temperature=STANDARD_AIR_TEMPERATURE,
pressure=AVERAGE_PRESSURE_MEAN_SEA_LEVEL,
latitude=DEFAULT_LATITUDE,
altitude=DEFAULT_ALTITUDE,
cmfs='CIE 1931 2 Degree Standard Observer',
**kwargs):
"""
Plots a single *Rayleigh* scattering spectral power distribution.
Parameters
----------
CO2_concentration : numeric, optional
:math:`CO_2` concentration in parts per million (ppm).
temperature : numeric, optional
Air temperature :math:`T[K]` in kelvin degrees.
pressure : numeric
Surface pressure :math:`P` of the measurement site.
latitude : numeric, optional
Latitude of the site in degrees.
altitude : numeric, optional
Altitude of the site in meters.
cmfs : unicode, optional
Standard observer colour matching functions.
Other Parameters
----------------
\**kwargs : dict, optional
{:func:`colour.plotting.render`},
Please refer to the documentation of the previously listed definition.
out_of_gamut_clipping : bool, optional
{:func:`colour.plotting.single_spd_plot`},
Whether to clip out of gamut colours otherwise, the colours will be
offset by the absolute minimal colour leading to a rendering on
gray background, less saturated and smoother.
Returns
-------
Figure
Current figure or None.
Examples
--------
>>> single_rayleigh_scattering_spd_plot() # doctest: +SKIP
"""
title = 'Rayleigh Scattering'
cmfs = get_cmfs(cmfs)
settings = {'title': title, 'y_label': 'Optical Depth'}
settings.update(kwargs)
spd = rayleigh_scattering_spd(cmfs.shape, CO2_concentration, temperature,
pressure, latitude, altitude)
return single_spd_plot(spd, **settings)
[docs]def the_blue_sky_plot(cmfs='CIE 1931 2 Degree Standard Observer', **kwargs):
"""
Plots the blue sky.
Parameters
----------
cmfs : unicode, optional
Standard observer colour matching functions.
Other Parameters
----------------
\**kwargs : dict, optional
{:func:`colour.plotting.render`},
Please refer to the documentation of the previously listed definition.
Returns
-------
Figure
Current figure or None.
Examples
--------
>>> the_blue_sky_plot() # doctest: +SKIP
"""
canvas(**kwargs)
cmfs, name = get_cmfs(cmfs), cmfs
ASTM_G_173_spd = ASTM_G_173_ETR.copy()
rayleigh_spd = rayleigh_scattering_spd()
ASTM_G_173_spd.align(rayleigh_spd.shape)
spd = rayleigh_spd * ASTM_G_173_spd
matplotlib.pyplot.subplots_adjust(hspace=0.4)
matplotlib.pyplot.figure(1)
matplotlib.pyplot.subplot(211)
settings = {
'title': 'The Blue Sky - Synthetic Spectral Power Distribution',
'y_label': u'W / m-2 / nm-1',
'standalone': False
}
settings.update(kwargs)
single_spd_plot(spd, name, **settings)
matplotlib.pyplot.subplot(212)
settings = {
'title':
'The Blue Sky - Colour',
'x_label': ('The sky is blue because molecules in the atmosphere '
'scatter shorter wavelengths more than longer ones.\n'
'The synthetic spectral power distribution is computed as '
'follows: '
'(ASTM G-173 ETR * Standard Air Rayleigh Scattering).'),
'y_label':
'',
'aspect':
None,
'standalone':
False
}
blue_sky_color = XYZ_to_sRGB(spectral_to_XYZ(spd))
single_colour_swatch_plot(
ColourSwatch('', normalise_maximum(blue_sky_color)), **settings)
settings = {'standalone': True}
settings.update(kwargs)
return render(**settings)