WebMaximus

Shadows in overcast conditions in P3Dv4

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Depends on what options you have ticked on.. Usually if it's overcast I only leave cloud shadows on and turn all others off for a performance benefit.

However if you leave cloud shadows off then even if it's overcast it would be casting shadows for autogen which would be very strange indeed. There are many combinations you can use so it's about finding that right one.

 

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Thanks, I know I can manually adjust everything related to shadows on the lighting screen under settings.

What I was thinking about is when I have it configured to have my own aircraft (or vehicle as it's called in P3D) cast shadows I obviously don't want this to happen unless the sun is actually shining. To have these shadows in overcast conditions when the sun is nowhere to be seen always felt very odd and unrealistic to me.

I was hoping maybe this was addressed now with all the talk about this new lighting stuff in P3Dv4.

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Here's an example to clarify my question.

Parked at gata A23 in Frankfurt and as seen in the screenshot it's far from a sunny day today with clouds as seen in the screenshot covering the complete sky and yet my aircraft is casting full blown shadows on the ground.

Will this still happen in P3Dv4?

YHrqK9F.jpg

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Yes it still happens... it's annoying.

I assume it's because clouds aren't really objects which cast real shadows, like buildings and simobjects. Cloud shadows are somehow 'baked' or something onto objects - but not all objects... Clouds don't recieve lighting from sources (airplanes don't light up clouds like in X-Plane) but are lit up ambient somehow. Also, clouds don't cast shadows on each other (which they should, if it were made correctly).

Don't really know if that made sense... :smile:

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OK, I'm sorry to hear that because I really had my hopes up for this to be fixed now with the new lighting features but thanks for the confirmation.

As for clouds not being objects in the right sense of the word that might be so but I still think it must be some way to let the simulator know that when the complete sky is covered with thick clouds then the sun won't make any objects cast shadows and the sun won't be shining into the cockpit causing v/c shadows.

Maybe in next version :laugh:

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6 minutes ago, WebMaximus said:

OK, I'm sorry to hear that because I really had my hopes up for this to be fixed now with the new lighting features but thanks for the confirmation.

As for clouds not being objects in the right sense of the word that might be so but I still think it must be some way to let the simulator know that when the complete sky is covered with thick clouds then the sun won't make any objects cast shadows and the sun won't be shining into the cockpit causing v/c shadows.

Maybe in next version :laugh:

Perhaps... It's my big hope, that LM will extend the dynamic lighting features of Prepar3D V4 into the clouds rendering also... so clouds get correct lighting from the sun and aircrafts can (finally) light up clouds as well... And overcast would look correctly as well, with shadows on the ground. I also hate, that you can still see the sun, when the visibility is low in FSX/Prepar3D. 

But we'll see.. I guess it would require a major overhaul of the weather engine and the way clouds are depicted... right now, they're flat textures, which turn to face your aircraft to make up for the fake 3D effect. Clouds should actually be some kind of 3D objects instead, or particle objects of some kind...

But I guess, that it would probably be quite taxiing on the system...

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What you suggest would be awesome but I'm afraid just as you say that will have to wait until LM finally decides to replace some of the ancient stuff their simulation platform still is based on if that will ever happen.

Guess the best option right now is to simply switch any unrealistic shadows off like was already suggested and by doing so, again as already suggested, will also save some resources that can be used for other things in the sim that work in a realistic way.

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You are all right, but my fear is that if this will be done via dynamic lighting/cloud rendering even best hardware will not be able to give us a resonable performance. Anyway, would be great if "no sun - no shadows" could be introduced somehow.

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14 minutes ago, Nemo said:

You are all right, but my fear is that if this will be done via dynamic lighting/cloud rendering even best hardware will not be able to give us a resonable performance. Anyway, would be great if "no sun - no shadows" could be introduced somehow.

How exactly should that be done?

Currently, Prepar3D can't even detect if clouds are blocking the sun... There's no 'light' in the physical sense present in Prepar3D - at least not previously. To begin with, it's ridiculous, that night textures is even needed, as night time would be obvious if there was no light present...! With Dynamic Lighting, they've begun an small overhaul of the lighting engine, and introduced real light sources, which illuminate objects and airplanes... I sincerly hope that this is extended to the rest of the world...
I'm not really sure how the cloud shadows are done in Prepar3D, but it's some fake workaround, since clouds aren't really objects which casts shadows (and have the ability to receive shadows). That's why the sun is visible in foggy conditions. That's why simobjects and airplanes still casts shadows, even though it's overcast...

I don't know how it's done, but I assume 'the sun' isn't a light source as such... The only logical thing would be some kind of ambient light, as the Sun as source - but not emitting source, but reference for shadows etc... 

Again, it's my great hope, that LM would take a look at this and generally overhaul the lighting engine and weather engine to that effect... 

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Mikeymike it depends on your GPU. It doesn't on my 1080.

On ‎7‎/‎26‎/‎2017 at 10:17 PM, Anders Bermann said:

How exactly should that be done?

Currently, Prepar3D can't even detect if clouds are blocking the sun... There's no 'light' in the physical sense present in Prepar3D - at least not previously. To begin with, it's ridiculous, that night textures is even needed, as night time would be obvious if there was no light present...! With Dynamic Lighting, they've begun an small overhaul of the lighting engine, and introduced real light sources, which illuminate objects and airplanes... I sincerly hope that this is extended to the rest of the world...
I'm not really sure how the cloud shadows are done in Prepar3D, but it's some fake workaround, since clouds aren't really objects which casts shadows (and have the ability to receive shadows). That's why the sun is visible in foggy conditions. That's why simobjects and airplanes still casts shadows, even though it's overcast...

I don't know how it's done, but I assume 'the sun' isn't a light source as such... The only logical thing would be some kind of ambient light, as the Sun as source - but not emitting source, but reference for shadows etc... 

Again, it's my great hope, that LM would take a look at this and generally overhaul the lighting engine and weather engine to that effect... 

Anders, you are dreaming of this:

https://en.wikipedia.org/wiki/Ray_tracing_(graphics)

Unfortunately, many years ago the 3D modelling world decided not to go down that technological path probably because it meant that 3D technology would have been too expensive for mass consumption. If they would have though, today Nvidia would have ray-traced optimized graphics cards already but we are still stuck with the primitive way of depicting shadows even in many other 3D apps other than flight sim. Will it ever change?

Cheers

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Yes, this is true - I experimented with C algorithms for Ray Tracing in the 80s.....took my Amiga a full day to render one simple image but the results were stunning when glass or mirrors were used.  I thought for sure that would be the way of the future - and actually it has been for the animation studios, they use ray-tracing for all their frames.  I feel some day this technique will be commonplace, just not sure when the consumer hardware will be there (studios have rendering farms).

Mark Trainer

 

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3 hours ago, glider1 said:

Mikeymike it depends on your GPU. It doesn't on my 1080.

Anders, you are dreaming of this:

https://en.wikipedia.org/wiki/Ray_tracing_(graphics)

Unfortunately, many years ago the 3D modelling world decided not to go down that technological path probably because it meant that 3D technology would have been too expensive for mass consumption. If they would have though, today Nvidia would have ray-traced optimized graphics cards already but we are still stuck with the primitive way of depicting shadows even in many other 3D apps other than flight sim. Will it ever change?

Cheers

Interesting, but no... Actually I'm not really sure what I'm dreaming of... 

But at least, that all objects would obey the physical laws with regards to lighting. All objects would have the ability to cast and receive light. Currently the sun i still visible in overcast conditions, and aircrafts and objects are casting shadows in such conditions. I would wish, that Lockheed-Martin would overhaul the lighting and weather engine, to such a degree, that clouds would be objects or particles (and not fake 3D - made of rotating 2D sprites which they are now) and they would have the ability to cast and receive shadows - not only on the ground but on other clouds as well. That aircraft landing lights, would have the ability to illuminate them etc... 

I hope you know where I'm going with this... 

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Here is a game that was rendered in ray tracing algorithms:

https://en.wikipedia.org/wiki/Quake_Wars:_Ray_Traced

Imagine if the flight sim were done that way. Only one surface texture definition for each object and an almost infinite number of possible visual effects that emerge out of the algorithm itself. It would save so much work for scenery designers. Problem is that because technology is advanced not by what is best but by what is most profitable, we are locked into the inferior rendering techniques that have a whole heap of unintended side effects like this thread has noticed.

 

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