Re: [Flightgear-devel] Volcanoes - an update

[Thorsten R. <tho...@sc...>]

> Hm, I think it might be generally easier (also easier to maintain) if
> we had this "ash-plasma" added to ALS itself. That would avoid possibly
> hundreds of implementations of the same thing. Sth like:
>
> // no idea about good numbers, just a wild guess!
> if (KIAS > 250 and AshDensity > 20%)
>   { do_the_ash_plasma_boogie; }
> if (KIAS > 2000)
>   { do_the_entry_plasma_boogie; }
>
> Obviously a Sopwith Camel won't reach sufficient speed to see this
> phenomenon, any airliner will.


Could do and it would be friendly for aircraft maintainers - but to have  
it with any aircraft by default, it'd have to go into the generic as well  
as the model-combined shader. That in turn means it'd get evaluated for  
pretty much every object in the scene (thousands of random buildings,...)

In 99.9999 % of all cases, the operation would yield nothing, because  
either the object is not moving at all, or because the object is not in  
ash.

It's still cost performance, because you always end up doing the  
calculation.

We do this for another 20 phenomena, and, well, our framerate takes a  
serious dive.

For that reason, I consistently prefer to bump the workload off *once* to  
aircraft maintainers rather than make the GPU work *every frame*.

* Thorsten