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fgdata/Environment/local-weather-rules.xml

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<?xml version="1.0" ?>
<!--
This file is part of FlightGear, the free flight simulator
http://www.flightgear.org/
Copyright (C) 2012 Torsten Dreyer, Torsten (at) t3r _dot_ de
This program is free software; you can redistribute it and/or
modify it under the terms of the GNU General Public License as
published by the Free Software Foundation; either version 2 of the
License, or (at your option) any later version.
This program is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
General Public License for more details.
-->
<!--
Compute Atmospheric Light Shading related properties
-->
<PropertyList>
<!-- (pi/2 - /sim/time/sun-angle-rad) / 0.017451 * 110000.0 -->
<filter>
<name>LocalWeather:terminator-relative-position</name>
<input>
<expression>
<difference>
<value>1.57079632675</value>
<property>/sim/time/sun-angle-rad</property>
</difference>
</expression>
</input>
<output>/environment/terminator-relative-position-m</output>
<type>gain</type>
<gain>6303363.70409</gain>
</filter>
<filter>
<name>LocalWeather:eye-altitude</name>
<input>
<property>/position/altitude-ft</property>
</input>
<output>/sim/rendering/eye-altitude-m</output>
<type>gain</type>
<gain>0.30480</gain>
</filter>
<!-- Properties used by the atmospheric scattering shader, when not being set directly
by Advanced Weather -->
<filter>
<!-- Ground visibility. Same as lowest boundary layer. -->
<name>EnvironmentInterpolator:AtmosphericShader:ground-visibility-m</name>
<type>gain</type>
<enable>
<condition>
<not>
<property>/nasal/local_weather/enabled</property>
<value>true</value>
</not>
</condition>
</enable>
<input>/environment/config/boundary/entry[0]/visibility-m</input>
<output>/environment/ground-visibility-m</output>
</filter>
<filter>
<!-- Ground haze level - assumed to be up to the lowest cloud layer. -->
<name>EnvironmentInterpolator:AtmosphericShader:GroundHazeThickness</name>
<type>gain</type>
<enable>
<condition>
<not>
<property>/nasal/local_weather/enabled</property>
<value>true</value>
</not>
</condition>
</enable>
<input>
<expression>
<sum>
<property>/environment/clouds/layer[0]/elevation-ft</property>
<property>/environment/clouds/layer[0]/thickness-ft</property>
</sum>
</expression>
</input>
<gain>
<!-- feet to meters -->
<value>0.3048</value>
</gain>
<u_min>
<value>0</value>
</u_min>
<u_max>
<!-- haze maxes out at 6000ft. Could probably do something using lapse rates instead -->
<value>2000</value>
</u_max>
<output>/environment/ground-haze-thickness-m</output>
</filter>
<!-- Build up the ground level scattering from 1 for clear skies to 0.6 for overcast -->
<filter>
<name>EnvironmentInterpolator:AtmosphericShader:GroundScattering:0:Clear</name>
<type>gain</type>
<enable>
<condition>
<and>
<not>
<property>/nasal/local_weather/enabled</property>
<value>true</value>
</not>
<equals>
<property>/environment/clouds/layer[0]/coverage</property>
<value>clear</value>
</equals>
</and>
</condition>
</enable>
<input>
<value>1</value>
</input>
<output>/environment/surface/ground-scattering</output>
</filter>
<filter>
<name>EnvironmentInterpolator:AtmosphericShader:GroundScattering:0:Few</name>
<type>gain</type>
<enable>
<condition>
<and>
<not>
<property>/nasal/local_weather/enabled</property>
<value>true</value>
</not>
<equals>
<property>/environment/clouds/layer[0]/coverage</property>
<value>few</value>
</equals>
</and>
</condition>
</enable>
<input>
<value>0.9</value>
</input>
<output>/environment/surface/ground-scattering</output>
</filter>
<filter>
<name>EnvironmentInterpolator:AtmosphericShader:GroundScattering:0:Scattered</name>
<type>gain</type>
<enable>
<condition>
<and>
<not>
<property>/nasal/local_weather/enabled</property>
<value>true</value>
</not>
<equals>
<property>/environment/clouds/layer[0]/coverage</property>
<value>scattered</value>
</equals>
</and>
</condition>
</enable>
<input>
<value>0.8</value>
</input>
<output>/environment/surface/ground-scattering</output>
</filter>
<filter>
<name>EnvironmentInterpolator:AtmosphericShader:GroundScattering:0:Broken</name>
<type>gain</type>
<enable>
<condition>
<and>
<not>
<property>/nasal/local_weather/enabled</property>
<value>true</value>
</not>
<equals>
<property>/environment/clouds/layer[0]/coverage</property>
<value>broken</value>
</equals>
</and>
</condition>
</enable>
<input>
<value>0.7</value>
</input>
<output>/environment/surface/ground-scattering</output>
</filter>
<filter>
<name>EnvironmentInterpolator:AtmosphericShader:GroundScattering:0:Overcast</name>
<type>gain</type>
<enable>
<condition>
<and>
<not>
<property>/nasal/local_weather/enabled</property>
<value>true</value>
</not>
<equals>
<property>/environment/clouds/layer[0]/coverage</property>
<value>overcast</value>
</equals>
</and>
</condition>
</enable>
<input>
<value>0.6</value>
</input>
<output>/environment/surface/ground-scattering</output>
</filter>
<!-- TODO: Handle layers beyond the first -->
<!-- Set the scattering at the aircraft level -->
<filter>
<name>EnvironmentInterpolator:AtmosphericShader:Scattering:AircraftAboveLayer</name>
<type>gain</type>
<enable>
<condition>
<and>
<not>
<property>/nasal/local_weather/enabled</property>
<value>true</value>
</not>
<greater-than>
<property>/position/altitude-ft</property>
<expression>
<sum>
<property>/environment/clouds/layer[0]/elevation-ft</property>
<property>/environment/clouds/layer[0]/thickness-ft</property>
</sum>
</expression>
</greater-than>
</and>
</condition>
</enable>
<input>
<value>1</value>
</input>
<output>/rendering/scene/scattering</output>
</filter>
<filter>
<name>EnvironmentInterpolator:AtmosphericShader:Scattering:AircraftBelowLayer</name>
<type>gain</type>
<enable>
<condition>
<and>
<not>
<property>/nasal/local_weather/enabled</property>
<value>true</value>
</not>
<less-than-equals>
<property>/position/altitude-ft</property>
<expression>
<sum>
<property>/environment/clouds/layer[0]/elevation-ft</property>
<property>/environment/clouds/layer[0]/thickness-ft</property>
</sum>
</expression>
</less-than-equals>
</and>
</condition>
</enable>
<input>/environment/surface/ground-scattering</input>
<output>/rendering/scene/scattering</output>
</filter>
<!-- Clouds self-shading -->
<filter>
<name>EnvironmentInterpolator:AtmosphericShader:CloudSelfShading</name>
<type>gain</type>
<enable>
<condition>
<not>
<property>/nasal/local_weather/enabled</property>
<value>true</value>
</not>
</condition>
</enable>
<input>
<!-- TODO : Make this sun-angle dependent -->
<value>1.0</value>
</input>
<output>/environment/cloud-self-shading</output>
</filter>
<!-- Skydome parameters - /sim/rendering/[mie|rayleigh|dome-density] -->
<filter>
<name>EnvironmentInterpolator:AtmosphericShader:Skydome:VisFactor</name>
<type>gain</type>
<enable>
<condition>
<not>
<property>/nasal/local_weather/enabled</property>
<value>true</value>
</not>
</condition>
</enable>
<input>
<expression>
<product>
<difference>
<property>/environment/visibility-m</property>
<value>30000</value>
</difference>
<value>0.000011111</value>
</product>
</expression>
</input>
<u_min>0.0</u_min>
<u_max>1.0</u_max>
<output>/sim/rendering/skydome-vis-factor</output>
</filter>
<filter>
<name>EnvironmentInterpolator:AtmosphericShader:Skydome:Rayleigh:Low</name>
<type>gain</type>
<enable>
<condition>
<and>
<not>
<property>/nasal/local_weather/enabled</property>
<value>true</value>
</not>
<less-than>
<property>/position/altitude-ft</property>
<value>36000</value>
</less-than>
</and>
</condition>
</enable>
<input>
<expression>
<difference>
<value>0.0003</value>
<product>
<property>/sim/rendering/skydome-vis-factor</property>
<value>0.0001</value>
</product>
</difference>
</expression>
</input>
<output>/sim/rendering/rayleigh-no-polution</output>
</filter>
<filter>
<name>EnvironmentInterpolator:AtmosphericShader:Skydome:Rayleigh:Medium</name>
<type>gain</type>
<enable>
<condition>
<and>
<not>
<property>/nasal/local_weather/enabled</property>
<value>true</value>
</not>
<greater-than>
<property>/position/altitude-ft</property>
<value>36000</value>
</greater-than>
<less-than>
<property>/position/altitude-ft</property>
<value>85000</value>
</less-than>
</and>
</condition>
</enable>
<input>
<expression>
<difference>
<difference>
<value>0.0003</value>
<product>
<property>/sim/rendering/skydome-vis-factor</property>
<value>0.0001</value>
</product>
</difference>
<product>
<difference>
<property>/position/altitude-ft</property>
<value>36000</value>
</difference>
<value>0.000000002</value>
</product>
</difference>
</expression>
</input>
<output>/sim/rendering/rayleigh-no-polution</output>
</filter>
<filter>
<name>EnvironmentInterpolator:AtmosphericShader:Skydome:Rayleigh:High</name>
<type>gain</type>
<enable>
<condition>
<and>
<not>
<property>/nasal/local_weather/enabled</property>
<value>true</value>
</not>
<greater-than>
<property>/position/altitude-ft</property>
<value>85000</value>
</greater-than>
</and>
</condition>
</enable>
<input>
<expression>
<difference>
<value>0.0002</value>
<product>
<property>/sim/rendering/skydome-vis-factor</property>
<value>0.0001</value>
</product>
</difference>
</expression>
</input>
<output>/sim/rendering/rayleigh-no-polution</output>
</filter>
<filter>
<name>EnvironmentInterpolator:AtmosphericShader:Skydome:Rayleight:Polution:Low</name>
<type>gain</type>
<enable>
<condition>
<and>
<not>
<property>/nasal/local_weather/enabled</property>
<value>true</value>
</not>
<less-than-equals>
<property>/position/altitude-ft</property>
<expression>
<sum>
<property>/environment/clouds/layer[0]/elevation-ft</property>
<property>/environment/clouds/layer[0]/thickness-ft</property>
</sum>
</expression>
</less-than-equals>
</and>
</condition>
</enable>
<input>
<expression>
<sum>
<property>/sim/rendering/rayleigh-no-polution</property>
<product>
<property>/environment/air-pollution-norm</property>
<value>0.0003</value>
</product>
<product>
<property>/environment/air-pollution-norm</property>
<value>0.0004</value>
<difference>
<value>1.0</value>
<product>
<div>
<property>/position/altitude-ft</property>
<sum>
<property>/environment/clouds/layer[0]/elevation-ft</property>
<property>/environment/clouds/layer[0]/thickness-ft</property>
<value>1.0</value><!-- to avoid divide by 0 exceptions -->
</sum>
</div>
<div>
<property>/position/altitude-ft</property>
<sum>
<property>/environment/clouds/layer[0]/elevation-ft</property>
<property>/environment/clouds/layer[0]/thickness-ft</property>
<value>1.0</value><!-- to avoid divide by 0 exceptions -->
</sum>
</div>
</product>
</difference>
</product>
</sum>
</expression>
</input>
<output>/sim/rendering/rayleigh</output>
</filter>
<filter>
<name>EnvironmentInterpolator:AtmosphericShader:Skydome:Rayleight:Polution:High</name>
<type>gain</type>
<enable>
<condition>
<and>
<not>
<property>/nasal/local_weather/enabled</property>
<value>true</value>
</not>
<greater-than>
<property>/position/altitude-ft</property>
<expression>
<sum>
<property>/environment/clouds/layer[0]/elevation-ft</property>
<property>/environment/clouds/layer[0]/thickness-ft</property>
</sum>
</expression>
</greater-than>
</and>
</condition>
</enable>
<input>
<expression>
<sum>
<property>/sim/rendering/rayleigh-no-polution</property>
<product>
<property>/environment/air-pollution-norm</property>
<value>0.0003</value>
</product>
</sum>
</expression>
</input>
<output>/sim/rendering/rayleigh</output>
</filter>
<filter>
<name>EnvironmentInterpolator:AtmosphericShader:Skydome:Mie:Low</name>
<type>gain</type>
<enable>
<condition>
<and>
<not>
<property>/nasal/local_weather/enabled</property>
<value>true</value>
</not>
<less-than>
<property>/position/altitude-ft</property>
<value>36000</value>
</less-than>
</and>
</condition>
</enable>
<input>
<expression>
<difference>
<value>0.005</value>
<product>
<property>/sim/rendering/skydome-vis-factor</property>
<value>0.002</value>
</product>
</difference>
</expression>
</input>
<output>/sim/rendering/mie</output>
</filter>
<filter>
<name>EnvironmentInterpolator:AtmosphericShader:Skydome:Mie:Medium</name>
<type>gain</type>
<enable>
<condition>
<and>
<not>
<property>/nasal/local_weather/enabled</property>
<value>true</value>
</not>
<greater-than>
<property>/position/altitude-ft</property>
<value>36000</value>
</greater-than>
<less-than>
<property>/position/altitude-ft</property>
<value>85000</value>
</less-than>
</and>
</condition>
</enable>
<input>
<expression>
<difference>
<difference>
<value>0.005</value>
<product>
<property>/sim/rendering/skydome-vis-factor</property>
<value>0.002</value>
</product>
</difference>
<product>
<difference>
<property>/position/altitude-ft</property>
<value>36000</value>
</difference>
<value>0.00000004</value>
</product>
</difference>
</expression>
</input>
<output>/sim/rendering/mie</output>
</filter>
<filter>
<name>EnvironmentInterpolator:AtmosphericShader:Skydome:Mie:High</name>
<type>gain</type>
<enable>
<condition>
<and>
<not>
<property>/nasal/local_weather/enabled</property>
<value>true</value>
</not>
<greater-than>
<property>/position/altitude-ft</property>
<value>85000</value>
</greater-than>
</and>
</condition>
</enable>
<input>
<expression>
<difference>
<value>0.003</value>
<product>
<property>/sim/rendering/skydome-vis-factor</property>
<value>0.002</value>
</product>
</difference>
</expression>
</input>
<output>/sim/rendering/mie</output>
</filter>
<!-- Density -->
<filter>
<name>EnvironmentInterpolator:AtmosphericShader:Skydome:Density:Low</name>
<type>gain</type>
<enable>
<condition>
<and>
<not>
<property>/nasal/local_weather/enabled</property>
<value>true</value>
</not>
<less-than-equals>
<property>/position/altitude-ft</property>
<expression>
<sum>
<property>/environment/clouds/layer[0]/elevation-ft</property>
<property>/environment/clouds/layer[0]/thickness-ft</property>
</sum>
</expression>
</less-than-equals>
</and>
</condition>
</enable>
<input>
<expression>
<sum>
<value>0.3</value>
<product>
<property>/environment/air-pollution-norm</property>
<value>0.05</value>
</product>
<product>
<property>/environment/air-pollution-norm</property>
<value>0.05</value>
<difference>
<value>1.0</value>
<product>
<div>
<property>/position/altitude-ft</property>
<sum>
<property>/environment/clouds/layer[0]/elevation-ft</property>
<property>/environment/clouds/layer[0]/thickness-ft</property>
<value>1.0</value><!-- to avoid divide by 0 exceptions -->
</sum>
</div>
<div>
<property>/position/altitude-ft</property>
<sum>
<property>/environment/clouds/layer[0]/elevation-ft</property>
<property>/environment/clouds/layer[0]/thickness-ft</property>
<value>1.0</value><!-- to avoid divide by 0 exceptions -->
</sum>
</div>
</product>
</difference>
</product>
</sum>
</expression>
</input>
<output>/sim/rendering/dome-density</output>
</filter>
<filter>
<name>EnvironmentInterpolator:AtmosphericShader:Skydome:Density:High</name>
<type>gain</type>
<enable>
<condition>
<and>
<not>
<property>/nasal/local_weather/enabled</property>
<value>true</value>
</not>
<greater-than>
<property>/position/altitude-ft</property>
<expression>
<sum>
<property>/environment/clouds/layer[0]/elevation-ft</property>
<property>/environment/clouds/layer[0]/thickness-ft</property>
</sum>
</expression>
</greater-than>
</and>
</condition>
</enable>
<input>
<expression>
<sum>
<value>0.3</value>
<product>
<property>/environment/air-pollution-norm</property>
<value>0.05</value>
</product>
</sum>
</expression>
</input>
<output>/sim/rendering/dome-density</output>
</filter>
<!-- Mean elevation. No easy way to do this, so we'll just use the altitude of the nearest METAR station -->
<filter>
<name>EnvironmentInterpolator:AtmosphericShader:Skydome:MeanElevation</name>
<type>gain</type>
<enable>
<condition>
<not>
<property>/nasal/local_weather/enabled</property>
<value>true</value>
</not>
</condition>
</enable>
<input>
<expression>
<product>
<property>/environment/metar[0]/station-elevation-ft</property>
<value>0.3048</value>
</product>
</expression>
</input>
<output>/environment/mean-terrain-elevation-m</output>
</filter>
<!-- Tree "season" - used to determine whether to display the trees in summer or winter foliage -->
<filter>
<name>EnvironmentInterpolator:Trees:Season:Summer</name>
<type>gain</type>
<enable>
<condition>
<not>
<or>
<equals>
<property>sim/startup/season</property>
<value>winter</value>
</equals>
<greater-than>
<property>/environment/season</property>
<value>1.5</value>
</greater-than>
</or>
</not>
</condition>
</enable>
<input>
<value>0.0</value>
</input>
<output>/environment/tree-season</output>
</filter>
<filter>
<name>EnvironmentInterpolator:Trees:Season:Winter</name>
<type>gain</type>
<enable>
<condition>
<or>
<equals>
<property>sim/startup/season</property>
<value>winter</value>
</equals>
<greater-than>
<property>/environment/season</property>
<value>1.5</value>
</greater-than>
</or>
</condition>
</enable>
<input>
<value>1.0</value>
</input>
<output>/environment/tree-season</output>
</filter>
<!-- Lighting parameter - used for city and road lighting during night -->
<filter>
<name>EnvironmentInterpolator:OSM:Lightmap:Night</name>
<type>gain</type>
<enable>
<condition>
<greater-than>
<property>/sim/time/sun-angle-rad</property>
<value>1.45</value>
</greater-than>
</condition>
</enable>
<input>
<value>1.0</value>
</input>
<output>/environment/lightmap-factor</output>
</filter>
<filter>
<name>EnvironmentInterpolator:OSM:Lightmap:Day</name>
<type>gain</type>
<enable>
<condition>
<not>
<greater-than>
<property>/sim/time/sun-angle-rad</property>
<value>1.45</value>
</greater-than>
</not>
</condition>
</enable>
<input>
<value>0.0</value>
</input>
<output>/environment/lightmap-factor</output>
</filter>
<!-- Daily variation of road traffic for the road shader -->
<filter>
<name>EnvironmentInterpolator:OSM:LocalTime</name>
<input>
<expression>
<sum>
<property>/sim/time/utc/day-seconds</property>
<property>/sim/time/local-offset</property>
</sum>
</expression>
</input>
<output>/sim/time/local-day-seconds</output>
<type>gain</type>
<gain>1.0</gain>
</filter>
<filter>
<name>EnvironmentInterpolator:OSM:LocalTimeOverrun</name>
<enable>
<condition>
<greater-than>
<property>/sim/time/local-day-seconds</property>
<value>86400.0</value>
</greater-than>
</condition>
</enable>
<input>
<expression>
<difference>
<property>/sim/time/local-day-seconds</property>
<value>86400</value>
</difference>
</expression>
</input>
<output>/sim/time/local-day-seconds</output>
<type>gain</type>
<gain>1.0</gain>
</filter>
<filter>
<name>EnvironmentInterpolator:OSM:LocalTimeUnderrun</name>
<enable>
<condition>
<less-than>
<property>/sim/time/local-day-seconds</property>
<value>0.0</value>
</less-than>
</condition>
</enable>
<input>
<expression>
<sum>
<property>/sim/time/local-day-seconds</property>
<value>86400</value>
</sum>
</expression>
</input>
<output>/sim/time/local-day-seconds</output>
<type>gain</type>
<gain>1.0</gain>
</filter>
<filter>
<name>EnvironmentInterpolator:OSM:TrafficDensity</name>
<type>gain</type>
<input>
<expression>
<table>
<property>/sim/time/local-day-seconds</property>
<entry><ind>0.0</ind><dep>0.32</dep></entry>
<entry><ind>3600.0</ind><dep>0.21</dep></entry>
<entry><ind>7200.0</ind><dep>0.18</dep></entry>
<entry><ind>10800.0</ind><dep>0.16</dep></entry>
<entry><ind>14400.0</ind><dep>0.19</dep></entry>
<entry><ind>18000.0</ind><dep>0.21</dep></entry>
<entry><ind>21600.0</ind><dep>0.45</dep></entry>
<entry><ind>25200.0</ind><dep>0.77</dep></entry>
<entry><ind>28800.0</ind><dep>1.30</dep></entry>
<entry><ind>32400.0</ind><dep>1.44</dep></entry>
<entry><ind>36000.0</ind><dep>1.04</dep></entry>
<entry><ind>39600.0</ind><dep>0.95</dep></entry>
<entry><ind>43200.0</ind><dep>1.03</dep></entry>
<entry><ind>46800.0</ind><dep>1.04</dep></entry>
<entry><ind>50400.0</ind><dep>1.10</dep></entry>
<entry><ind>54000.0</ind><dep>1.30</dep></entry>
<entry><ind>57600.0</ind><dep>1.50</dep></entry>
<entry><ind>61200.0</ind><dep>1.26</dep></entry>
<entry><ind>64800.0</ind><dep>0.92</dep></entry>
<entry><ind>68400.0</ind><dep>0.72</dep></entry>
<entry><ind>72000.0</ind><dep>0.56</dep></entry>
<entry><ind>75600.0</ind><dep>0.52</dep></entry>
<entry><ind>79200.0</ind><dep>0.45</dep></entry>
<entry><ind>82800.0</ind><dep>0.36</dep></entry>
</table>
</expression>
</input>
<output>/sim/rendering/osm/road-traffic-daily-variation</output>
</filter>
<!-- illumination setting for precipitation particles -->
<filter>
<name>EnvironmentInterpolator:Precipitation:Illumination</name>
<type>gain</type>
<enable>
<condition>
<property>/environment/precipitation-control/detailed-precipitation</property>
</condition>
</enable>
<input>
<expression>
<sum>
<property>/rendering/scene/diffuse/red</property>
<value>0.3</value>
<product>
<property>/sim/rendering/als-secondary-lights/use-searchlight</property>
<value>0.3</value>
</product>
<product>
<property>/sim/rendering/als-secondary-lights/use-landing-light</property>
<value>0.3</value>
</product>
<product>
<property>/sim/rendering/als-secondary-lights/use-alt-landing-light</property>
<value>0.3</value>
</product>
</sum>
</expression>
</input>
<output>/environment/precipitation-control/illumination</output>
<min>0.0</min>
<max>1.0</max>
</filter>
<filter>
<name>EnvironmentInterpolator:Precipitation:SurfaceWetness</name>
<type>noise-spike</type>
<max-rate-of-change>0.004</max-rate-of-change>
<input>/environment/rain-norm</input>
<output>/environment/surface/wetness</output>
<min><property>/environment/surface/wetness-set</property></min>
<max>1.0</max>
</filter>
<filter>
<name>EnvironmentInterpolator:Aurora:LatitudeDep</name>
<type>gain</type>
<gain>1.0</gain>
<input>
<expression>
<pow>
<div>
<abs>
<property>/position/latitude-deg</property>
</abs>
<value>90</value>
</div>
<value>2.0</value>
</pow>
</expression>
</input>
<output>/environment/aurora/latitude-scale</output>
</filter>
<filter>
<name>EnvironmentInterpolator:Aurora:VerticalSize</name>
<type>gain</type>
<gain>1.0</gain>
<input>
<expression>
<max>
<pow>
<property>/environment/aurora/latitude-scale</property>
<value>2.0</value>
</pow>
<value>0.1</value>
</max>
</expression>
</input>
<output>/environment/aurora/vsize</output>
</filter>
<filter>
<name>EnvironmentInterpolator:Aurora:HorizontalSize</name>
<type>gain</type>
<gain>1.0</gain>
<input>
<expression>
<max>
<property>/environment/aurora/latitude-scale</property>
<value>0.1</value>
</max>
</expression>
</input>
<output>/environment/aurora/hsize</output>
</filter>
<filter>
<name>EnvironmentInterpolator:Aurora:Strength</name>
<type>gain</type>
<gain>1.0</gain>
<input>
<expression>
<product>
<pow>
<property>/environment/aurora/latitude-scale</property>
<value>0.5</value>
</pow>
<property>/environment/aurora/set-strength</property>
</product>
</expression>
</input>
<output>/environment/aurora/strength</output>
</filter>
</PropertyList>