Dynamic Lighting Shadow Cast

[AnkH 2,232]

Hi all, somehow rather surprising but I really do not find anything on this topic. Are you guys not bothered by the fact that dynamic lighting does not cast shadows? Just last night I was flying out of ImagineSim's WSSS, an airport with lovely dynamic lighting, and I realized that all those dynamic lights do not cast shadows (or more precisely, objects lit by DL do not cast shadows). Is this something I can change by using a certain setting or modifying the config or is this simply not provided? What do you think? Would it ruin the performance totally? To me, I am happy that I did not notice it until yesterday, because as soon as I notice such a flaw, I will always recognize it in future flights and it will hamper the immersion for me...

[Iceman2 110]

1 hour ago, Rob_Ainscough said:

DL casting of shadows is probably more suitable for Ray Tracing (i.e. DX12 with RT extensions) ... so who knows what the future might bring.

Cheers, Rob.

Interesting.. thanks Rob, I only just mentioned this issue to Symbol over at AI lights Reborn a few hours ago saying I find it annoying when AI traffic taxi up behind you at night and their DL taxi lights light up your cockpit like daytime.

Real bummer LM don’t want to add shadows but I’m no software expert so I shouldn’t complain. (Too much)

[AnkH 2,232]

Ok, bummer. It would be nice if one could at least modify certain dynamic lights to cast shadows, e.g. the fixed light poles on an airport scenery...

[simbol 5,767]

2 hours ago, Iceman2 said:

Interesting.. thanks Rob, I only just mentioned this issue to Symbol over at AI lights Reborn a few hours ago saying I find it annoying when AI traffic taxi up behind you at night and their DL taxi lights light up your cockpit like daytime.

Real bummer LM don’t want to add shadows but I’m no software expert so I shouldn’t complain. (Too much)

I will try to find ways to improve the situation as I suggested to you via my forums.

But I will also try to speak with LM developers to see if anything can be done in the future, they are very open minded, so I am sure they will think or suggest something useful.

Regards,
S.

[virtuali 4,419]

I would imagine this feature to be possibly very hard on fps. Consider how much shadow can affect fps now, especially at high levels of quality, and that's with just a single light source casting ( the Sun ).

DL casting shadows would ideally have to have each one of them casting its own individual shadow, with all the complex interactions when multiple light sources cast at the same time ( think a football field at night, with multiple light pylons ).

[Pilot53 543]

Why cant P3d use dynamic lighting the way Xplane does?  Aren't all lights in xplane, including the sun, dynamic with much less penalty compared to p3d?

[simbol 5,767]

2 hours ago, virtuali said:

I would imagine this feature to be possibly very hard on fps. Consider how much shadow can affect fps now, especially at high levels of quality, and that's with just a single light source casting ( the Sun ).

DL casting shadows would ideally have to have each one of them casting its own individual shadow, with all the complex interactions when multiple light sources cast at the same time ( think a football field at night, with multiple light pylons ).

Hi Umberto,

Totally agree, however Iceman2 was commenting in my forums how is he also annoyed by the fact your cockpit gets totally lighten up when an airplane is taxing behind you, which it should as in reality the light should not bleed inside the cabin at that angle.

I have experienced this too and I admit it is a bit weird..  so I am thinking in ways LM could prevent that event instead of implementing shadows, etc.

S.

[Pilot53 543]

3 hours ago, Rob_Ainscough said:

I’ll double check, but pretty sure XP11’s dynamic light don’t cast shadows either ... I seem to recall testing that some time ago ... but I’ll check again.

Cheers, Rob.

Rob, isn't all lighting dynamic lighting in xplane, even sunlight?

[AnkH 2,232]

Well, thanks for the clarification, Rob. It would still be nice if for example the lights that are dynamic but with a static position, e.g. light poles on an airport etc., would cast shadows. No need for my taxi light casting shadows, this would be for SURE to much performance loss. But those static light sources? Then at least all planes sitting on their gates would cast shadows like in daytime... it simply looks odd during night time that the own plane and the ai planes somehow sit on an illuminated tarmac without shadows...

Besides this, I doubt that DX12 and RT is really necessary. There are plenty of engines around that offer shadow casting of dynamic lights already for several years without RT or DX12. It is just another fact showing how outdated the flightsimming engines actually are...

[virtuali 4,419]

5 hours ago, AnkH said:

There are plenty of engines around that offer shadow casting of dynamic lights already for several years without RT or DX12. 

No, they use lots of very clever methods to trick you into assuming something is dynamic, when it isn't:

https://docs.unity3d.com/Manual/BestPracticeMakingBelievableVisuals9.html

Some background info:

https://docs.unity3d.com/Manual/LightModes-TechnicalInformation.html

Quote

Ray tracing is a very elegant way of solving this problem in computer graphics, as it tries to simulate what actually happens in the real world by following ray paths through the scene. The movie industry has entirely moved to ray tracing at this point for generating their images.

Unfortunately, ray tracing is still too slow to be used in most real time graphics,

 

[AnkH 2,232]

3 hours ago, Rob_Ainscough said:

I'll disagree, but if you can show me a game that has multiple dynamic lights all casting shadows in real-time over 5-10mi distances,

You see, that is the difference between my suggestion and your "super perfect" solution you are thinking of ;-) But, there is absoltely no need for multiple DL casting shadows over such huge distances of 5-10mi, for the sake of immersion, it would already make a hell lot of a difference if (I repeat myself...) the DL of those static light poles on airports would cast shadows. That would not even be one mile. Not even half of a mile... just some hundred meters.

And that is what I was thinking of with my comparison to games: a reduced yet immersive variant of DL shadow casting. Or a "tricked" one, as Umberto wrote. It would already be enough if the taxi light on the front gear would be such a DL, again no need to go for the super-mega-perfect solution (means AI, GSX vehicles and all other mobile stuff does not necessarily need to have shadow casting lights...).

Anyway...

Edited September 6, 2019 by AnkH

[_Gladius_ 24]

5-10 miles isn’t the distance that the light is casting the shadow, it represents the distance at which YOU can see the shadow, and would therefore need it rendered.

If there was a setting that would allow you to set a distance at which shadows are rendered, similar to cloud shadows, that would be nice.  Then at least, the user is in control.

[simbol 5,767]

Maybe, only cast the DL shadows on the user aircraft instead of the entire environment? that at least will improve things a bit with a compromise?

S.