This class defines objects containing lighting and weather specifications that can later be applied in carla.World. So far, these conditions only intervene with [sensor.camera.rgb](ref_sensors.md#rgb-camera). They neither affect the actor's physics nor other sensors.
Each of these parameters acts indepently from the rest. Increasing the rainfall will not automatically create puddles nor change the road's humidity. That makes for a better customization but means that realistic conditions need to be scripted. However an example of dynamic weather conditions working realistically can be found [here](https://github.com/carla-simulator/carla/blob/master/PythonAPI/examples/dynamic_weather.py).
Determines the creation of puddles. Values range from 0 to 100, being 0 none at all and 100 a road completely capped with water. Puddles are created with static noise, meaning that they will always appear at the same locations.
Controls the strenght of the wind with values from 0, no wind at all, to 100, a strong wind. The wind does affect rain direction and leaves from trees, so this value is restricted to avoid animation issues.
Density of the fog (as in specific mass) from 0 to infinity. The bigger the value, the more dense and heavy it will be, and the fog will reach smaller heights. Corresponds to <a href="https://docs.unrealengine.com/en-US/Engine/Actors/FogEffects/HeightFog/index.html#:~:text=Using%20Exponential%20Height%20Fog%20Features,-The%20sections%20below&text=Add%20a%20second%20fog%20layer,height%20falloff%2C%20and%20height%20offset">Fog Height Falloff</a> in the UE docs. <br> If the value is 0, the fog will be lighter than air, and will cover the whole scene. <br> A value of 1 is approximately as dense as the air, and reaches normal-sized buildings. <br> For values greater than 5, the air will be so dense that it will be compressed on ground level.
Controls how much the light will contribute to volumetric fog. When set to 0, there is no contribution.
# --------------------------------------
- var_name:mie_scattering_scale
type:float
doc:>
Controls interaction of light with large particles like pollen or air pollution resulting in a hazy sky with halos around the light sources. When set to 0, there is no contribution.
# --------------------------------------
- var_name:rayleigh_scattering_scale
type:float
doc:>
Controls interaction of light with small particles like air molecules. Dependent on light wavelength, resulting in a blue sky in the day or red sky in the evening.
Controls how much the light will contribute to volumetric fog. When set to 0, there is no contribution.
- param_name:mie_scattering_scale
type:float
default:0.0
doc:>
Controls interaction of light with large particles like pollen or air pollution resulting in a hazy sky with halos around the light sources. When set to 0, there is no contribution.
- param_name:rayleigh_scattering_scale
type:float
default:0.0331
doc:>
Controls interaction of light with small particles like air molecules. Dependent on light wavelength, resulting in a blue sky in the day or red sky in the evening.
Method to initialize an object defining weather conditions. This class has some presets for different noon and sunset conditions listed in a note below.
