Illuminate the airport buildings and props at night

[dvanmosselbeen]

Description about the feature

Except a few buildings at EBBR and some landmarks in Brussels, most objects are plain black at night. The scenery give a strange feeling at night and is so unrealistic.

A light animation could improve the night experience. This is essentially useful at all airports and airfields that are susceptible to be used in the dark. Thinking too: EBAW, EBBL, EBCF, EBCI, EBGB, EBOS, EBSG, EBSW. Later on we could apply this effect to other objects if needed.

Are you willing to contribute about this feature
Yes

Additional comments

There's different ways to animate objects for night by for example changing it's texture file at night like done at some buildings at EBBR. But we want somethings more lightweight at first instance and the following emission animation at a very low value seems to be a very good alternative and fairly realistic.

<!--  night emission  -->
<animation>
    <type>material</type>
    <object-name>Hangar</object-name>
    <condition>
        <greater-than>
            <property>/sim/time/sun-angle-rad</property>
            <value>1.49</value>
        </greater-than>
    </condition>
    <emission>
        <red>0.1</red>
        <green>0.1</green>
        <blue>0.1</blue>
    </emission>
</animation>

Thanks to this animation, the emission is only set at night. In contrast of a fixed emission value on a blender material, which could also emit at day light. We want to keep the emission value as low as possible. For some bigger objects a value of 0.2 can be used but not much more. A high emission value could pop out the object to much and make things unrealistic, we want a subtle light effect.

This change request implies that we need to make use of a xml file for this animation to work, and to adjust the concerned stg file to point to this xml file instead of the ac object. Using xml files is more resource demanding. So we need to pay attention to not overload the scenery and only use this feature for buildings and props that really needs to pop out at night. Higher density regions could be seriously impacted if abused with xml files.

[UPDATED] 21/08/2019

• Updated content of the report to match current report markup guidelines.

[dvanmosselbeen]

EBCI didn't made it as this airport is in it's early stage with it's base blocs and basic textures. It's useless to apply this night animation as EBCI still needs to be textured.

However, some other airfields not listed in the initial request where also done.

[dvanmosselbeen]

So far this all looks way better as it did before at night. This emission night animation isn't perfect, nor realistic, but it's the most realistic with these settings and the less expensive method for this moment. This emission trick with these values isn't a wow change, but more than enough to not have all building showing pitch black at night. So our goal is been achieved.

FlightGear doesn't have a "true" lighting system and we did what we could to have the best user experience at night.

From now on, we are going to use this emission animation trick as long as there's nothing better.