"""Radiance raytracing Parameters."""
from ._advancedparametersbase import AdvancedRadianceParameters
from ._defaultset import rtrace_number_parameters, rtrace_boolean_parameters
from ._frozen import frozen
[docs]@frozen
class RtraceParameters(AdvancedRadianceParameters):
"""Radiance Parameters for grid based analysis.
For the full list of attributes try self.keys
Attributes:
quality: An integer between 0-2 (0:low, 1: medium or 2: high quality)
Usage:
rp = RtraceParameters(0)
print(rp.to_rad_string())
> -aa 0.25 -ab 2 -ad 512 -dc 0.25 -st 0.85 -lw 0.05 -as 128 -ar 16 -lr 4
-dt 0.5 -dr 0 -ds 0.5 -dp 64
rp = RtraceParameters(1)
print(rp.to_rad_string())
> -aa 0.2 -ab 3 -ad 2048 -dc 0.5 -st 0.5 -lw 0.01 -as 2048 -ar 64 -lr 6
-dt 0.25 -dr 1 -ds 0.25 -dp 256
rp = RtraceParameters(2)
print(rp.to_rad_string())
> -aa 0.1 -ab 6 -ad 4096 -dc 0.75 -st 0.15 -lw 0.005 -as 4096 -ar 128
-lr 8 -dt 0.15 -dr 3 -ds 0.05 -dp 512
rp.ab = 5
rp.u = True
print(rp.to_rad_string())
> -aa 0.1 -ab 5 -dj 0.7 -ad 4096 -dc 0.75 -st 0.15 -lw 0.005 -as 4096
-ar 128 -lr 8 -dt 0.15 -dr 3 -ds 0.05 -dp 512 -u
"""
def __init__(self, quality=None):
"""Create Radiance paramters."""
AdvancedRadianceParameters.__init__(self)
self.add_radiance_number('ab', descriptive_name='ambient bounces',
attribute_name="ambient_bounces", num_type=int)
self.ambient_bounces = None
""" Number of ambient bounces. This is the maximum number of diffuse
bounces computed by the indirect calculation. A value of zero
implies no indirect calculation."""
self.add_radiance_number('ad', descriptive_name='ambient divisions',
attribute_name="ambient_divisions", num_type=int)
self.ambient_divisions = None
""" Number of ambient divisions. The error in the Monte Carlo calculation
of indirect illuminance will be inversely proportional to the square
root of this number. A value of zero implies no indirect calculation.
"""
self.add_radiance_number('as', descriptive_name='ambient super samples',
attribute_name='ambient_supersamples', num_type=int)
self.ambient_supersamples = None
""" Number of ambient super-samples. Super-samples are applied only to
the ambient divisions which show a significant change.
"""
self.add_radiance_number('ar', descriptive_name='ambient resolution',
attribute_name='ambient_resolution', num_type=int)
self.ambient_resolution = None
""" Number of ambient resolution. This number will determine the maximum
density of ambient values used in interpolation. Error will start to
increase on surfaces spaced closer than the scene size divided by the
ambient resolution. The maximum ambient value density is the scene
size times the ambient accuracy."""
self.add_radiance_number('aa', descriptive_name='ambient accuracy',
attribute_name='ambient_accuracy', num_type=float)
self.ambient_accuracy = None
"""Number of ambient accuracy. This value will approximately equal the
error from indirect illuminance interpolation. A value of zero implies
no interpolation."""
self.add_radiance_number('dj', descriptive_name='direct source jitter',
attribute_name='direct_jitter', num_type=float)
self.direct_jitter = None
"""
-dj frac
Set the direct jittering to frac. A value of zero samples each source
at specific sample points (see the -ds option below), giving a smoother
but somewhat less accurate rendering. A positive value causes rays to
be distributed over each source sample according to its size,
resulting in more accurate penumbras. This option should never be
greater than 1, and may even cause problems (such as speckle)when the
value is smaller. A warning about aiming failure will issued if frac is
too large. It is usually wise to turn off image sampling when using
direct jitter by setting -ps to 1.
"""
self.add_radiance_number('ds', descriptive_name='direct sampling',
attribute_name='direct_sampling', num_type=float)
self.direct_sampling = None
"""
-ds frac
Set the direct sampling ratio to frac. A light source will be subdivided
until the width of each sample area divided by the distance to the
illuminated point is below this ratio. This assures accuracy in regions
close to large area sources at a slight computational expense. A value
of zero turns source subdivision off, sending at most one shadow ray to
each light source.
"""
self.add_radiance_number('dt', descriptive_name='direct thresholding',
num_type=float, attribute_name='direct_threshold')
self.direct_threshold = None
"""
-dt frac
Set the direct threshold to frac. Shadow testing will stop when the
potential contribution of at least the next and at most all remaining
light source samples is less than this fraction of the accumulated value.
The remaining light source contributions are approximated statistically.
A value of zero means that all light source samples will be tested for
shadow.
"""
self.add_radiance_number('dc', descriptive_name='direct certainty',
num_type=float, attribute_name='direct_certainty')
self.direct_certainty = None
"""
-dc frac
Set the direct certainty to frac. A value of one guarantees that the
absolute accuracy of the direct calculation will be equal to or better
than that given in the -dt specification. A value of zero only insures
that all shadow lines resulting in a contrast change greater than the
-dt specification will be calculated.
"""
self.add_radiance_number('dr', descriptive_name='direct relays',
num_type=int, attribute_name='direct_sec_relays')
self.direct_sec_relays = None
"""
-dr N
Set the number of relays for secondary sources to N. A value of 0 means
that secondary sources will be ignored. A value of 1 means that sources
will be made into first generation secondary sources; a value of 2 means
that first generation secondary sources will also be made into second
generation secondary sources, and so on.
"""
self.add_radiance_number('dp', descriptive_name='direct presampling density',
num_type=int, attribute_name='direct_presamp_density')
self.direct_presamp_density = None
"""
-dp D
Set the secondary source presampling density to D. This is the number of
samples per steradian that will be used to determine ahead of time
whether or not it is worth following shadow rays through all the
reflections and/or transmissions associated with a secondary source path.
A value of 0 means that the full secondary source path will always be
tested for shadows if it is tested at all.
"""
self.add_radiance_number('st', descriptive_name='specular threshold',
num_type=float, attribute_name='specular_threshold')
self.specular_threshold = None
"""
-st frac
Set the specular sampling threshold to frac. This is the minimum
fraction of reflection or transmission, under which no specular sampling
is performed. A value of zero means that highlights will always be
sampled by tracing reflected or transmitted rays. A value of one means
that specular sampling is never used. Highlights from light sources
will always be correct, but reflections from other surfaces will be
approximated using an ambient value. A sampling threshold between zero
and one offers a compromise between image accuracy and rendering time.
"""
self.add_radiance_number('lw', descriptive_name='limit weight',
num_type=float, attribute_name='limit_weight')
self.limit_weight = None
"""
-lw frac
Limit the weight of each ray to a minimum of frac. During ray-tracing,
a record is kept of the estimated contribution (weight) a ray would have
in the image. If this weight is less than the specified minimum and the
-lr setting (above) is positive, the ray is not traced. Otherwise,
Russian roulette is used to continue rays with a probability equal to
the ray weight divided by the given frac.
"""
self.add_radiance_number('lr', descriptive_name='limit reflections',
num_type=int, attribute_name='limit_reflections')
self.limit_reflections = None
"""
-lr N
Limit reflections to a maximum of N, if N is a positive integer. If N
is zero, then Russian roulette is used for ray termination, and the
-lw setting (below) must be positive. If N is a negative integer, then
this sets the upper limit of reflections past which Russian roulette
will be used. In scenes with dielectrics and total internal reflection,
a setting of 0 (no limit) may cause a stack overflow.
"""
self.add_radiance_number('ss', descriptive_name='specular sampling',
num_type=float, attribute_name='specular_sampling')
self.specular_sampling = None
"""
-ss samp
Set the specular sampling to samp. For values less than 1, this is the
degree to which the highlights are sampled for rough specular materials.
A value greater than one causes multiple ray samples to be sent to reduce
noise at a commmesurate cost. A value of zero means that no jittering
will take place, and all reflections will appear sharp even when they
should be diffuse. This may be desirable when used in combination with
image sampling to obtain faster renderings.
"""
self.add_radiance_bool_flag('I', descriptive_name='irradiance calculation',
attribute_name='irradiance_calc')
self.irradiance_calc = None
"""
-I
Boolean switch to compute irradiance rather than radiance, with the
input origin and direction interpreted instead as measurement point and
orientation. -h Boolean switch for information header on output. The
radiance default value for this option is False.
"""
# TODO(sarith)
self.add_radiance_bool_flag('i', descriptive_name='irradiance calculation',
attribute_name='i_irradiance_calc')
self.i_irradiance_calc = None
"""
-i
Boolean switch to compute irradiance rather than radiance values. This
only affects the final result, substituting a Lambertian surface and
multiplying the radiance by pi. Glass and other transparent surfaces are
ignored during this stage. Light sources still appear with their original
radiance values, though the -dv option (below) may be used to override
this. This option is especially useful in conjunction with ximage(1)
for computing illuminance at scene points
"""
self.add_radiance_bool_flag('u', descriptive_name='uncorrelated random sampling',
attribute_name='uncor_rand_samp')
self.uncor_rand_samp = None
"""
-u
Boolean switch to control uncorrelated random sampling. When "off", a
low-discrepancy sequence is used, which reduces variance but can result
in a brushed appearance in specular highlights. When "on", pure Monte
Carlo sampling is used in all calculations.
"""
self.add_radiance_value('f', 'output data format',
attribute_name='output_data_format', is_joined=True)
self.output_data_format = None
"""
-f[io]
Format input according to the character i and output according to the
character o. Rtrace understands the following input and output formats:
'a' for ascii, 'f' for single-precision floating point, and 'd' for
double-precision floating point. In addition to these three choices, the
character 'c' may be used to denote 4-byte floating point (Radiance) color
format for the output of values only (-ov option, below). If the output
character is missing, the input format is used.
"""
self.add_radiance_value('o', 'output spec',
attribute_name='output_spec', is_joined=True)
self.output_spec = None
"""
-o[spec]
Produce output fields according to spec. Characters are interpreted as follows:
o - origin (input)
d - direction (normalized)
v - value (radiance)
V - contribution (radiance)
w - weight
W - color coefficient
l - effective length of ray
L - first intersection distance
c - local (u,v) coordinates
p - point of intersection
n - normal at intersection (perturbed)
N - normal at intersection (unperturbed)
s - surface name
m - modifier name
M - material name
~ tilde (end of trace marker)
If the letter `t` appears in spec, then the fields following will be printed for
every ray traced, not just the final result. If the capital letter `T` is given
instead of `t`, then all rays will be reported, including shadow testing rays to
light sources. Spawned rays are indented one tab for each level. The tilde
marker (`~`) is a handy way of differentiating the final ray value from daughter
values in a traced ray tree, and usually appears right before the `t` or `T`
output flags. E.g., -ov~TmW will emit a tilde followed by a tab at the end of
each trace, which can be easily distinguished even in binary output.
"""
self.try_to_unfreeze()
self.quality = quality or 0
"""An integer between 0-2 (0:low, 1: medium or 2: high quality)"""
self.freeze()
[docs] @classmethod
def from_json(cls, rec_json):
"""Create radiance parameters from json.
{
"gridbased_parameters": string // A standard radiance parameter string
(e.g. -ab 5 -aa 0.05 -ar 128)
}
"""
parameters = cls()
parameters.import_parameter_values_from_string(rec_json["gridbased_parameters"])
return parameters
@property
def isGridBasedRadianceParameters(self):
"""Return True to indicate this object is a RadianceParameters."""
return True
@property
def quality(self):
"""Get and set quality.
An integer between 0-2 (0:low, 1: medium or 2: high quality)
"""
return self._quality
@quality.setter
def quality(self, value):
value = int(value) or 0
assert 0 <= value <= 2, \
"Quality can only be 0:low, 1: medium or 2: high quality"
self._quality = value
"""An integer between 0-2 (0:low, 1: medium or 2: high quality)"""
# add all numeric parameters
for name, data in rtrace_number_parameters.items():
self.add_radiance_number(data['name'], data['dscrip'], num_type=data['type'],
attribute_name=name)
setattr(self, name, data['values'][value])
# add boolean parameters
for name, data in rtrace_boolean_parameters.items():
self.add_radiance_bool_flag(data['name'], data['dscrip'],
attribute_name=name)
setattr(self, name, data['values'][value])
[docs] def get_parameter_default_value_based_on_quality(self, parameter):
"""Get parameter value based on quality.
You can change this value by using self.parameter = value (e.g. self.ab=5)
Args:
parameter: Radiance parameter as an string (e.g "ab")
Usage:
rp = LowQuality()
print rp.getParameterValue("ab")
>> 2
"""
if not self.quality:
print("Quality is not set! use self.quality to set the value.")
return None
__key = str(parameter)
assert __key in self.keys, \
"%s is not a valid radiance parameter" % str(parameter)
return rtrace_number_parameters[__key]["values"][self.quality]
[docs] def to_json(self):
"""Write radiance grid_based parameters to json.
{
"gridbased_parameters": string // A standard radiance parameter string
(e.g. -ab 5 -aa 0.05 -ar 128)
}
"""
return {"gridbased_parameters": self.to_rad_string()
}
[docs]class LowQuality(RtraceParameters):
"""Radiance parmaters for a quick analysis."""
def __init__(self):
"""Create low quality radiance parameters for quick studies."""
RtraceParameters.__init__(self, quality=0)
[docs]class MediumQuality(RtraceParameters):
"""Medium quality Radiance parmaters."""
def __init__(self):
"""Create medium quality radiance parameters."""
RtraceParameters.__init__(self, quality=1)
[docs]class HighQuality(RtraceParameters):
"""High quality radiance parameters."""
def __init__(self):
"""Create high quality radiance parameters."""
RtraceParameters.__init__(self, quality=2)