"""Radiance Glass Material.
http://radsite.lbl.gov/radiance/refer/ray.html#Glass
"""
from __future__ import division
import math
from .materialbase import Material
import honeybee.typing as typing
from ladybug.rootfinding import secant
[docs]class Glass(Material):
"""Radiance glass material.
Args:
identifier: Text string for a unique Material ID. Must not contain spaces
or special characters. This will be used to identify the object across
a model and in the exported Radiance files.
r_transmissivity: Transmissivity for red. The value should be between 0 and 1
(Default: 0).
g_transmissivity: Transmissivity for green. The value should be between 0
and 1 (Default: 0).
b_transmissivity: Transmissivity for blue. The value should be between 0 and
1 (Default: 0).
refraction_index: Index of refraction. Typical values are 1.52 for float
glass and 1.4 for ETFE. If None, Radiance will default to using 1.52
for glass (Default: None).
modifier: Material modifier (Default: None).
dependencies: A list of primitives that this primitive depends on. This
argument is only useful for defining advanced primitives where the
primitive is defined based on other primitives. (Default: [])
Properties:
* identifier
* display_name
* r_transmissivity
* g_transmissivity
* b_transmissivity
* refraction_index
* average_transmissivity
* average_transmittance
* values
* modifier
* dependencies
* is_modifier
* is_material
Usage:
.. code-block:: python
glass_material = Glass("generic_glass", .65, .65, .65)
print(glass_material)
"""
__slots__ = ('_r_transmissivity', '_g_transmissivity', '_b_transmissivity',
'_refraction_index')
def __init__(self, identifier, r_transmissivity=0.0, g_transmissivity=0.0,
b_transmissivity=0.0, refraction_index=None, modifier=None,
dependencies=None):
"""Create glass material."""
Material.__init__(self, identifier, modifier=modifier,
dependencies=dependencies)
self.r_transmissivity = r_transmissivity
self.g_transmissivity = g_transmissivity
self.b_transmissivity = b_transmissivity
self.refraction_index = refraction_index
self._update_values()
def _update_values(self):
"""Populate dictionary values."""
if self.refraction_index:
self._values[2] = [
self.r_transmissivity, self.g_transmissivity, self.b_transmissivity,
self.refraction_index
]
else:
self._values[2] = [
self.r_transmissivity, self.g_transmissivity, self.b_transmissivity
]
@property
def r_transmissivity(self):
"""Get or set the transmissivity for red channel.
The value should be between 0 and 1 (Default: 0).
"""
return self._r_transmissivity
@r_transmissivity.setter
def r_transmissivity(self, transmissivity):
self._r_transmissivity = \
typing.float_in_range(transmissivity, 0, 1, 'red transmissivity')
@property
def g_transmissivity(self):
"""Get or set the transmissivity for green channel.
The value should be between 0 and 1 (Default: 0).
"""
return self._g_transmissivity
@g_transmissivity.setter
def g_transmissivity(self, transmissivity):
self._g_transmissivity = \
typing.float_in_range(transmissivity, 0, 1, 'green transmissivity')
@property
def b_transmissivity(self):
"""get or set the transmissivity for blue channel.
The value should be between 0 and 1 (Default: 0).
"""
return self._b_transmissivity
@b_transmissivity.setter
def b_transmissivity(self, transmissivity):
self._b_transmissivity = \
typing.float_in_range(transmissivity, 0, 1, 'blue transmissivity')
@property
def refraction_index(self):
"""Get or set the index of refraction.
Typical values are 1.52 for float glass and 1.4 for ETFE. If None, Radiance
will default to using 1.52 for glass.
"""
return self._refraction_index
@refraction_index.setter
def refraction_index(self, value):
self._refraction_index = \
typing.float_in_range(value, 1, input_name='refraction index') \
if value is not None else None
@property
def r_transmittance(self):
"""Get or set the transmittance for red channel."""
return self.transmittance_from_transmissivity(self.r_transmissivity)
@r_transmittance.setter
def r_transmittance(self, value):
self.r_transmissivity = self.transmissivity_from_transmittance(value)
@property
def g_transmittance(self):
"""Get or set the transmittance for green channel."""
return self.transmittance_from_transmissivity(self.g_transmissivity)
@g_transmittance.setter
def g_transmittance(self, value):
self.g_transmissivity = self.transmissivity_from_transmittance(value)
@property
def b_transmittance(self):
"""Get or set the transmittance for blue channel."""
return self.transmittance_from_transmissivity(self.b_transmissivity)
@b_transmittance.setter
def b_transmittance(self, value):
self.b_transmissivity = self.transmissivity_from_transmittance(value)
@property
def average_transmissivity(self):
"""Get the average transmissivity.
The value is calculated by multiplying the r, g, b values by v-lambda.
"""
return 0.265 * self.r_transmissivity + \
0.670 * self.g_transmissivity + 0.065 * self.b_transmissivity
@property
def average_transmittance(self):
"""Get the average transmittance.
The value is calculated by multiplying the r, g, b values by v-lambda.
"""
return self.transmittance_from_transmissivity(self.average_transmissivity)
[docs] @classmethod
def from_transmittance(cls, identifier, r_transmittance=0.0, g_transmittance=0.0,
b_transmittance=0.0, refraction_index=None, modifier=None,
dependencies=None):
"""Create glass material from transmittance values.
Radiance uses transmissivity values while glass manufactures provide the value
for transmittance. This method does the conversion from transmittance to
transmissivity.
Args:
identifier: Text string for a unique Material ID. Must not contain spaces
or special characters. This will be used to identify the object across
a model and in the exported Radiance files.
r_transmittance: Transmittance for red. The value should be between 0 and 1
(Default: 0).
g_transmittance: Transmittance for green. The value should be between 0 and 1
(Default: 0).
b_transmittance: Transmittance for blue. The value should be between 0 and 1
(Default: 0).
refraction_index: Index of refraction. Typical values are 1.52 for float
glass and 1.4 for ETFE. If None, Radiance will default to using 1.52
for glass (Default: None).
modifier: Material modifier (Default: None).
dependencies: A list of primitives that this primitive depends on. This
argument is only useful for defining advanced primitives where the
primitive is defined based on other primitives. (Default: [])
Usage:
.. code-block:: python
glass_material = Glass.from_transmittance("generic_glass", .60, .60, .60)
print(glass_material)
"""
rt = cls.transmissivity_from_transmittance(r_transmittance)
gt = cls.transmissivity_from_transmittance(g_transmittance)
bt = cls.transmissivity_from_transmittance(b_transmittance)
return cls(identifier, rt, gt, bt, refraction_index, modifier,
dependencies=dependencies)
[docs] @classmethod
def from_single_transmissivity(cls, identifier, rgb_transmissivity=0,
refraction_index=None, modifier=None,
dependencies=None):
"""Create glass material with single transmissivity value.
Args:
identifier: Text string for a unique Material ID. Must not contain spaces
or special characters. This will be used to identify the object across
a model and in the exported Radiance files.
rgb_transmissivity: Transmissivity for red, green and blue. The value should
be between 0 and 1 (Default: 0).
refraction_index: Index of refraction. Typical values are 1.52 for float
glass and 1.4 for ETFE. If None, Radiance will default to using 1.52
for glass (Default: None).
modifier: Material modifier (Default: None).
dependencies: A list of primitives that this primitive depends on. This
argument is only useful for defining advanced primitives where the
primitive is defined based on other primitives. (Default: [])
Usage:
.. code-block:: python
glassMaterial = Glass.from_single_transmissivity("generic glass", .65)
print(glassMaterial)
"""
return cls(
identifier, r_transmissivity=rgb_transmissivity,
g_transmissivity=rgb_transmissivity, b_transmissivity=rgb_transmissivity,
refraction_index=refraction_index,
modifier=modifier, dependencies=dependencies)
[docs] @classmethod
def from_single_transmittance(cls, identifier, rgb_transmittance=0,
refraction_index=None, modifier=None,
dependencies=None):
"""Create glass material with single transmittance value.
Args:
identifier: Text string for a unique Material ID. Must not contain spaces
or special characters. This will be used to identify the object across
a model and in the exported Radiance files.
rgb_transmittance: Transmittance for red, green and blue. The value should
be between 0 and 1 (Default: 0).
refraction_index: Index of refraction. Typical values are 1.52 for float
glass and 1.4 for ETFE. If None, Radiance will default to using 1.52
for glass (Default: None).
modifier: Material modifier (Default: None).
dependencies: A list of primitives that this primitive depends on. This
argument is only useful for defining advanced primitives where the
primitive is defined based on other primitives. (Default: [])
Usage:
.. code-block:: python
glassMaterial = Glass.from_single_transmittance("generic glass", .65)
print(glassMaterial)
"""
rgb_transmissivity = cls.transmissivity_from_transmittance(rgb_transmittance)
return cls(
identifier,
r_transmissivity=rgb_transmissivity, g_transmissivity=rgb_transmissivity,
b_transmissivity=rgb_transmissivity, refraction_index=refraction_index,
modifier=modifier, dependencies=dependencies)
[docs] @classmethod
def from_primitive_dict(cls, primitive_dict):
"""Initialize Glass from a primitive dict.
Args:
data: A dictionary in the format below.
.. code-block:: python
{
"modifier": {}, # primitive modifier (Default: None)
"type": "glass", # primitive type
"identifier": "", # primitive identifier
"display_name": "", # primitive display name
"values": [] , # values
"dependencies": []
}
"""
cls._dict_type_check(cls.__name__, primitive_dict)
modifier, dependencies = cls.filter_dict_input(primitive_dict)
values = primitive_dict['values'][2]
refraction_index = values[3] if len(values) == 4 else None
cls_ = cls(
identifier=primitive_dict['identifier'],
r_transmissivity=values[0],
g_transmissivity=values[1],
b_transmissivity=values[2],
refraction_index=refraction_index,
modifier=modifier,
dependencies=dependencies)
if 'display_name' in primitive_dict and \
primitive_dict['display_name'] is not None:
cls_.display_name = primitive_dict['display_name']
# update the values from values dictionary.
# this might look redundant but it is to ensure any strange input like inputs in
# strings line are updated and will be the same as input in cases that user uses
# from_string classmethod
cls_.values = primitive_dict['values']
return cls_
[docs] @classmethod
def from_dict(cls, data):
"""Initialize Glass from a dictionary.
Args:
data: A dictionary in the format below.
.. code-block:: python
{
"type": "Glass",
"identifier": "", # Material identifier
"display_name": "", # Material display name
"r_transmissivity": float, # Transmissivity for red
"g_transmissivity": float, # Transmissivity for green
"b_transmissivity": float, # Transmissivity for blue
"refraction_index": float, # Index of refraction
"modifier": {}, # material modifier (Default: None)
"dependencies": []
}
"""
cls._dict_type_check(cls.__name__, data)
modifier, dependencies = cls.filter_dict_input(data)
new_obj = cls(identifier=data["identifier"],
r_transmissivity=data["r_transmissivity"],
g_transmissivity=data["g_transmissivity"],
b_transmissivity=data["b_transmissivity"],
refraction_index=data["refraction_index"],
modifier=modifier,
dependencies=dependencies)
if 'display_name' in data and data['display_name'] is not None:
new_obj.display_name = data['display_name']
return new_obj
[docs] def to_dict(self):
"""Translate this object to a dictionary."""
base = {
'modifier': self.modifier.to_dict(),
'type': 'Glass',
'identifier': self.identifier,
'r_transmissivity': self.r_transmissivity,
'g_transmissivity': self.g_transmissivity,
'b_transmissivity': self.b_transmissivity,
'refraction_index': self.refraction_index,
'dependencies': [dp.to_dict() for dp in self.dependencies]
}
if self._display_name is not None:
base['display_name'] = self.display_name
return base
[docs] @staticmethod
def transmissivity_from_transmittance(transmittance):
"""Calculate transmissivity based on transmittance value.
Transmissivity is the amount of light not absorbed in one traversal of
the material.
Transmittance (the value usually measured) is the total light transmitted
through the material pane including multiple reflections inside of the
glass pane.
"""
transmittance = float(transmittance)
return Glass._transmissivity_from_transmittance(transmittance)
[docs] @staticmethod
def transmittance_from_transmissivity(transmissivity):
"""Calculate transmittance based on transmissivity value.
Transmittance (the value usually measured) is the total light transmitted
through the material pane including multiple reflections inside of the
glass pane.
Transmissivity is the amount of light not absorbed in one traversal of
the material.
"""
transmissivity = float(transmissivity)
if transmissivity == 0:
return 0
def fn(x):
return Glass._transmissivity_from_transmittance(x) - transmissivity
return secant(0.01, 1, fn, 0.01)
@staticmethod
def _transmissivity_from_transmittance(transmittance):
"""Get transmissivity from a transmittance value"""
try:
tms = (math.sqrt(0.8402528435 + 0.0072522239 * (transmittance ** 2)) -
0.9166530661) / 0.0036261119 / transmittance
return tms if tms > 0 else 0
except ZeroDivisionError:
return 0
def __copy__(self):
mod, depend = self._dup_mod_and_depend()
new_obj = self.__class__(
self.identifier, self.r_transmissivity, self.g_transmissivity,
self.b_transmissivity, self.refraction_index, mod, depend)
new_obj._display_name = self._display_name
return new_obj