Volcanoes

[fmg]

Unfortunately I never get the Export-script to work. Anyone here who got it running?

[vnts]

Katla eruption from a distance (low lod) viewed from near Vik i Myrdal (BIVI). Rain & lightning in background.



Awe-some .

Nightlies (link) seem fine now (checked on Windows). Nightlies now have first 2 Iceland volcanos AIUI. Limited time with FG recently, so only checked from UFO (& BIVI).

Katla is much more scary than Eyjafjallajokull , the neighbour volcano that caused problems to aviation in 2010 (Katla's min eruption size is as bad. Eyjafjallajokull normally triggers Katla). Katla is overdue for eruption unfortunately.

If Katla erupts strongly the old coastline & picturesque villages may only continue to exist in digital reconstructions like in FG !. (Katla is sitting under a glacier which can explosively vapourise from a large eruption, and there may(?) well be a colossal wall of ice, water, and debris as that some of that mountain gets displaced. AIUI In general Icelandic lava is not viscous much like Hawaiian lava. So dissolved gasses don't build up explosively - lava rivers & fountains instead.)

Kind regards

[Thorsten]

Southern Iceland should be really interesting now - I've just added Surtsey to the list of active volcanoes - rather small-scale when compared with Katla, but worth a sightseeing trip to Heimaey to take a look.

[OO ZVY]

Iceland volcano tour.
















https://fgtracker.ml/modules/fgtracker/ ... ID=7456420

[wlbragg]

I'm almost ready to ask for a merge request to fgdata for a new volcano. Mount Nyiragongo in the Virunga National Park. Who knows, you might even see a mountain gorilla if you look really close.

Full eruption from a distance




Active from a distance


Active close up




I might try to implement Thorsten's idea to model a couple lava flows over the rim and down the sides. Something like you see in the Google images. Something else that would be really cool is a distance nighttime visual effect (atmosphere glow) as in the Google images.

[Thorsten]

Something else that would be really cool is a distance nighttime visual effect (atmosphere glow) as in the Google images.

That's fairly easy - use the lightning code for clouds like for the night launch of the Shuttle, then at least you see it on the clouds.

[wlbragg]

OK, I'll take a look.

[wlbragg]

@Thorsten

Which effect? Can you narrow it down, and as to what it is applied to? The only thing I could find that might be what your referring to is...

Code: Select all

<?xml version="1.0" encoding="utf-8"?>
<PropertyList>
  <name>shuttle-main</name>
  <inherits-from>Effects/space-combined</inherits-from>
  <parameters>
   <geo_light_r type="float"><use>/lighting/effects/geo-red</use></geo_light_r>
   <geo_light_g type="float"><use>/lighting/effects/geo-green</use></geo_light_g>
   <geo_light_b type="float"><use>/lighting/effects/geo-blue</use></geo_light_b>
   <geo_light_x type="float"><use>/lighting/effects/geo-x</use></geo_light_x>
   <geo_light_y type="float"><use>/lighting/effects/geo-y</use></geo_light_y>
   <geo_light_z type="float"><use>/lighting/effects/geo-z</use></geo_light_z>
   <geo_light_radius type="float"><use>/lighting/effects/geo-r</use></geo_light_radius>
   <geo_ambience type="float"><use>/lighting/effects/geo-ambience</use></geo_ambience>
</PropertyList>
  </parameters>

And would it be applied to what, the lava.ac mesh or something else? I fiddled around with this and it did turn the eruption glow into a orangish effect and still looked normal in the daylight. I didn't notice any clouds glowing, but this was a total guess as to what is needed.

[Thorsten]

Wrong place - there's slots in the cloud rendering code to make the clouds glow with the lightning flash - the weather sets them from Nasal, there's a center position as well as a color. These are just properties in the tree that you can set, not an effect you need to declare.

[wlbragg]

Ah, ok, I think I understand. When you said lightning, you meant lightning. I took it as lighting. Thanks.

[wlbragg]

I thought you were referring to the night time shuttle launch and the glow from the srb. I guess that was illuminating the fuselage, not the environment. I don't know why I thought it also effected the clouds.
.

[Thorsten]

I don't know why I thought it also effected the clouds.

Because it does affect the clouds - it utilizes the same lightning properties weather does, just with a different color and position.

[wlbragg]

Ok, even more clear now. Thanks.

While I'm asking questions, any reason against making the volcano code in the form of an addon instead of directly in fgdata?
It seems like the perfect candidate for an addon.

[wlbragg]

@Thorsten, or anyone if they know, why is /rendering/scene/diffuse/green VS /rendering/scene/diffuse/red used to set the start and end colors of the smoke and ash particle effect? I thought we typically use /rendering/scene/diffuse/red for controlling the lighting coming from the scene? Is it the same difference, were just using it for its emissive value? In this case though, because it is setting the color strength, why not use all three r=r, g=g, b=b? Wouldn't that be more accurate in passing emissive values per color? Or am I missing what this is being used for?

Code: Select all

<particle>
       <start>
          <color>
            <red>
               <property>/rendering/scene/diffuse/green</property>
            </red>
            <green>
               <property>/rendering/scene/diffuse/green</property>
            </green>
            <blue>
               <property>/rendering/scene/diffuse/green</property>
            </blue>
               <alpha>
                  <value>0.6</value>
               </alpha>
          </color>
          <size>
             <value>50.0</value>
          </size>
       </start>
       <end>
          <color>
             <red>
                  <property>/rendering/scene/diffuse/green</property>
               </red>
               <green>
                  <property>/rendering/scene/diffuse/green</property>
               </green>
               <blue>
                  <property>/rendering/scene/diffuse/green</property>
               </blue>
               <alpha>
                  <value>0.1</value>
               </alpha>
          </color>

I thought it was the erroneously placed effect I applied that I was getting red smoke particle effects at night, I see now that it is already being introduced to the effect, I assume through the above code. So I am still left wondering why green?

[wlbragg]

Hum, I was experimenting to see if I could answer the emissive question myself and used r, g, and b for the color values, It appears that the red shift at night no longer happens. Why does this work this way by using only green? When I stop and think about it, either way doesn't seem like it should change the effect to a more red value as your using the same value to adjust each color equally as the scene lighting changes. What am I missing?