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Philbert
04-30-2019, 02:11 AM
I love the Physical Sky in 2019 but if you aim the camera down even a little everything under the horizon is jet black. Is there anything you can do to change it? I'm doing an arch-viz style video and wouldn't have enough ground to go on forever and hide it.

gar26lw
04-30-2019, 07:01 AM
id be praying to the dpont god ;)

Kryslin
04-30-2019, 07:20 AM
@Philbert : You could, you know, submit a feature request for it to duplicate dpont's sunsky's functionality.

dpont's sunsky does work with LW 2018+. He updated it to do so sometime last year.

Sensei has an infinite plane plugin, but unknown whether it works in 2018+ or not. He'd have to clarify.

You don't need an infinite plane, either. Just a couple of kilometers... which you can set up in modeler, one of the basic modeling functions in layout, or using a null w/ a shape in layout...

prometheus
04-30-2019, 07:35 AM
I love the Physical Sky in 2019 but if you aim the camera down even a little everything under the horizon is jet black. Is there anything you can do to change it? I'm doing an arch-viz style video and wouldn't have enough ground to go on forever and hide it.

Itīs only logical, anything under the horizon should be nothing, unless there is something:D
So just add a groundplane, I usually add a groundplane at the size of 12km, but you can make it even bigger.

As mentioned,dp sunsky has a mirror function that helps for somethings, I think he updated it for 2019, but the physical sky and sunsky differs a bit.
But I donīt see no reason to not add a groundplane.

Ztreem
04-30-2019, 10:06 AM
Itīs only logical, anything under the horizon should be nothing, unless there is something:D


Is it? I thought the atmosphere was kind of spherical. :)

Philbert
04-30-2019, 12:56 PM
I guess I just have to make a ground plane. I like the idea of having no geometry though, it renders faster. I was hoping I could just continue the bottom most color all the way down.

Tobian
05-01-2019, 02:57 AM
Just layer a gradient over the top of the physical sky, with a solid colour in -Y and an alpha of 100% in +Y, and blend it slightly if you need a slight falloff. Hopefully some sort of simple fix is implemented soon, but this does work, I've tested it.

Philbert
05-01-2019, 03:05 AM
Oh great thanks I didn't expect you could combine them.

prometheus
05-01-2019, 04:14 AM
Is it? I thought the atmosphere was kind of spherical. :)

the atmosphere is spherical, so is the earth..and the atmosphere doesnīt really penetrate the spherical earth..thus the obscuring cut off, so I think the logic sort of extens well to the real thing as well, unless the earth is flat.
If we start to think no earth..you may think there would only be atmosphere and no cut off, but you see..no mass, no atmosphere at all.

Itīs not an event horizon..itīs just land & earth horizon.

Tobian
05-01-2019, 04:38 AM
It doesn't mix with the bg gradient, but the layers and layered textures all work as with anything else in that editor.

Ztreem
05-01-2019, 05:29 AM
the atmosphere is spherical, so is the earth..and the atmosphere doesnīt really penetrate the spherical earth..thus the obscuring cut off, so I think the logic sort of extens well to the real thing as well, unless the earth is flat.
If we start to think no earth..you may think there would only be atmosphere and no cut off, but you see..no mass, no atmosphere at all.

Itīs not an event horizon..itīs just land & earth horizon.

But now we are in a 3D app and not in reality. With your logic (that may be physically correct) we would not be able to even add a physical sky if the scene is empty and the sky would conform to the shape of the objects in the scene if you don’t first create a planet volume.

prometheus
05-01-2019, 05:49 AM
But now we are in a 3D app and not in reality. With your logic (that may be physically correct) we would not be able to even add a physical sky if the scene is empty and the sky would conform to the shape of the objects in the scene if you don’t first create a planet volume.

Well..It seems we have different ways of looking at what is logic and where that fitīs in, I really donīt follow you on this counter logic you brought forth on of how to treat the semantics within the 3D world.
You are restricting my logic to only be valid out of a point off reality world and the physical behaviors there in...I donīt make a complete bond to that realism, just a fraction..which is that the physical sky tries to simulate the real world
look, not the complete physics..which as you say would require a planet volume.

The output is similar, no earth...then it would be just pure blackness, why would we "Logicly" expect a physical sky that goes beneath the horizon?..when there in the 3d world isnīt any need for it to simulate the look of the real world.
The fact that the Threadstarter would like it to have such option is a completely different matter versus the logic of what should be expected as output in real world as well as 3d world for the equeal look in these referenced worlds.

I am all for options though to have a non horizon option for occasions when that could be needed, and you know what..I think it was me who put that suggestion to Denis and his sunsky plugin to make a way to avoid the sharp cutoff horizon, so he made a mirror function...I think that was suggested due to how the background fog worked ..which could cause a sharp edge in the fog otherwise, but other than that..it has no real good use for realism..since the earth always has a horizon (unless foggy day) and the question about being render effective without any geometry wasnīt the target either.

So again..when refering to logicly, that pertains to giving results equal to the real world...not actually simulating the whole planet..which some other landscape dedicated software may do to some extent.

Ztreem
05-01-2019, 06:40 AM
Well..It seems we have different ways of looking at what is logic and where that fitīs in, I really donīt follow you on this counter logic you brought forth on of how to treat the semantics within the 3D world.
You are restricting my logic to only be valid out of a point off reality world and the physical behaviors there in...I donīt make a complete bond to that realism, just a fraction..which is that the physical sky tries to simulate the real world
look, not the complete physics..which as you say would require a planet volume.

The ouput is similar...no earth pure blackness, why would we expect logicly a physical sky that goes beneath the horizon?..when there in the 3d world isnīt any need for it to simulate the look of the real world.
The fact that the Threadstarter would like it so is a completely different matter.

As I see it, we are in a 3d app and not bound to reality. So in the real world you can not take the earth away but in 3d you can and still have the atmosphere so it would be logical in that sense that you would see the sky continue beneath the horizon. But maybe I’m the only one with that kind of logic. Who cares, most physical sky systems work the same way as in LW, logic or not.

prometheus
05-01-2019, 06:48 AM
As I see it, we are in a 3d app and not bound to reality. So in the real world you can not take the earth away but in 3d you can and still have the atmosphere so it would be logical in that sense that you would see the sky continue beneath the horizon. But maybe I’m the only one with that kind of logic. Who cares, most physical sky systems work this way, logic or not.

I think you fail to see the point of my views, and you are restricting this logic to a certain referenceframe that is different to the logic of the reference frame I proposing..itīs not about making the 3d world act as a world reality simulator, it is referenced to what is excpected to be seen if you have something or nothing in the scene..and for that I assert my logic within that reference is valid.

I get what you mean about the logic of sky continue beyond the horizon..that is logic for a state of.."nothing prevents it to be so in the 3d world" but itīs in my views completely illogical in the reference of what we expect a physical sky tool to provide to simulate the real looks.

vue and terragen perhaps works in these manners of simulating the earth and sky...but for lightwave, this is just a background physical sky, it isnīt even volumetric or spectral..but it does what it was intended to do as basic as possible, and that means a horizon which also is a reference to albedo etc, where would you put the albedo with a continious sky?

Most physical sky system works in what way? which software do you reference to?
Blender has it yes..but there is a distinction between a supposed horison as well, itīs just that itīs softer with a color similar to the sky and not pure black...but the look would be completely wrong if you aim for realism look and have that in there without any ground.

The softer continued "sky" in blender for instance...doesnīt have any color grading shift as opposed to the sky that is above the horizon soft edge, it just tints the backdrop with a color as close to the ending albedo or horizon sky, it may yield a softer nicer look..but ultimately wrong if you want realism in the output look.

MarkAH
05-01-2019, 11:16 AM
Wouldn't you have some sort of terrain, or streets, parks, landscaping?
What, you would put all the struggling landscape architects out of business?
No! Not that!
OK, what I've found with these various Sky simulators is that almost always the horizon is fixed.
Doesn't seem to be a way move it.
So...
I have some landscaping.
Gotta have landscaping or your buildings are just floating in space, right?
I parent everything that isn't parented to something else, to the landscape, or terrain.
Even parent the camera to the landscape, and get the camera angle, focal length etc, so all the designs look nice.
Add the Sky simulator, and then just tilt the landscape to where the horizon looks nice to you.

Philbert
05-01-2019, 01:20 PM
There shouldn't have to be a landscape or buildings. Sometimes I just want to show off a single model like a car or plane and I like how the sky looks

prometheus
05-01-2019, 03:05 PM
There shouldn't have to be a landscape or buildings. Sometimes I just want to show off a single model like a car or plane and I like how the sky looks

Again, physical sky wasnīt made for such intent..and even in blender there isnīt any Sky continuing going on down below the horizon, it just tints the background with a close by color to the ending of the sky at the horizon edge.
you can install dpont sunsky and get similar and use non edge or mirror mode for the sunsky.

or use this scene I just set up with a mix of physical sky and textured environment.

See attached lws file.

144866

Philbert
05-01-2019, 03:10 PM
A color similar to the horizon is all I want. It's just the solid black that's ugly.

prometheus
05-01-2019, 03:19 PM
A color similar to the horizon is all I want. It's just the solid black that's ugly.

load my file.

Ztreem
05-01-2019, 03:43 PM
A color similar to the horizon is all I want. It's just the solid black that's ugly.

Use vpr and color pick the color you want close to the horizon.

Ztreem
05-01-2019, 03:54 PM
I think you fail to see the point of my views, and you are restricting this logic to a certain referenceframe that is different to the logic of the reference frame I proposing..itīs not about making the 3d world act as a world reality simulator, it is referenced to what is excpected to be seen if you have something or nothing in the scene..and for that I assert my logic within that reference is valid.

I get what you mean about the logic of sky continue beyond the horizon..that is logic for a state of.."nothing prevents it to be so in the 3d world" but itīs in my views completely illogical in the reference of what we expect a physical sky tool to provide to simulate the real looks.

vue and terragen perhaps works in these manners of simulating the earth and sky...but for lightwave, this is just a background physical sky, it isnīt even volumetric or spectral..but it does what it was intended to do as basic as possible, and that means a horizon which also is a reference to albedo etc, where would you put the albedo with a continious sky?

Most physical sky system works in what way? which software do you reference to?
Blender has it yes..but there is a distinction between a supposed horison as well, itīs just that itīs softer with a color similar to the sky and not pure black...but the look would be completely wrong if you aim for realism look and have that in there without any ground.

The softer continued "sky" in blender for instance...doesnīt have any color grading shift as opposed to the sky that is above the horizon soft edge, it just tints the backdrop with a color as close to the ending albedo or horizon sky, it may yield a softer nicer look..but ultimately wrong if you want realism in the output look.

Maybe its the physical word together with a black color beneath the horizon that I can’t accept as logical. When I read physical sky I maybe think more of a physical atmosphere. I just think that if we could look through earth with xray we would not see a black line at the horizon and that is physical correct to me.

prometheus
05-01-2019, 04:55 PM
Maybe its the physical word together with a black color beneath the horizon that I can’t accept as logical. When I read physical sky I maybe think more of a physical atmosphere. I just think that if we could look through earth with xray we would not see a black line at the horizon and that is physical correct to me.

I think itīs too confusing trying to fuse Physical correctness within the 3d world.. from a standpoint of what can not be in real world, namely se through the earth with xray, and expect not to see a black line in the horizon..in fact what we would see with that approach is just pure blackness, that is more physical correct ..if we ever could state something like that with xray and seeing through earth:D

You are expecting some kind of atmosphere that is spherical without any horizon, fair enough..not physical correct in any way, though we can imagine..and even create such 3d model.

- - - Updated - - -


Use vpr and color pick the color you want close to the horizon.

Use pick from screen with color picker and hover over horizon....if I should add to that trick, that is what I did in my posted scene.

prometheus
05-01-2019, 05:05 PM
You could just use a large 60km groundplane, this one is set to standard material and cel shading model..should render faster.
Picked color with color from screen and choose the horizon color.


https://forums.newtek.com/attachment.php?attachmentid=144872&d=1556751870
144872

Ztreem
05-01-2019, 06:12 PM
You are expecting some kind of atmosphere that is spherical without any horizon, fair enough..not physical correct in any way, though we can imagine..and even create such 3d model.


That is exactly what the atmosphere is, Spherical without a horizon, but we can't see it as the world is round, but the horizon is actually not there or real it's just an illusion that the land and sky meet.
As I stated before most if not all physical skies system in 3d graphics work like it does in Lightwave with a cut off at the horizon, so it's logical that it does the same in LW. But it's not logical to think that if we hypothetically could see beneath the horizon that it would be a black line there, that's just phyiscally impossible as the horizon is just a fictional line. When we use a physical sky in a 3d app without any object that form a horizon the black line loses it's logic. That's all I'm gonna say on this topic.

prometheus
05-01-2019, 06:52 PM
That is exactly what the atmosphere is, Spherical without a horizon, but we can't see it as the world is round, but the horizon is actually not there or real it's just an illusion that the land and sky meet.
As I stated before most if not all physical skies system in 3d graphics work like it does in Lightwave with a cut off at the horizon, so it's logical that it does the same in LW. But it's not logical to think that if we hypothetically could see beneath the horizon that it would be a black line there, that's just phyiscally impossible as the horizon is just a fictional line. When we use a physical sky in a 3d app without any object that form a horizon the black line loses it's logic. That's all I'm gonna say on this topic.

I donīt agree..the horizon is as it is, and thatīs all I have to say about that..and not because my name is Gump, but because Itīs bedtime.:D

jwiede
05-03-2019, 02:46 PM
I donīt agree..the horizon is as it is, and thatīs all I have to say about that..and not because my name is Gump, but because Itīs bedtime.:D

The problem with that logic is that in both reality and 3D uses, non-trivial scenarios arise where viewers can see "beneath" the horizon line, and thus need some kind of coverage.

For an example of a real-world case, when there's a depression/gorge/whatever situated right around the same distance as the horizon "terminator", it is sometimes possible (by looking "down the gorge", esp. when the gorge's "exit" is at lower elevation than its "entrance") to see sky that's technically "below the horizon". If there's no provision for showing sky below the horizon, those situations become problematic. Another real-world case is when the viewer is rising in elevation relative to the ground -- as their elevation rises (the angle between the viewer-horizon line and tangent at horizon increases), the viewer will see sky that was previously hiddden by the horizon.

Having a sudden transition to black is much more likely to cause additional work for users versus retaining that same "final color" across the entire view hemisphere beneath the "horizon", because users don't need to worry about accidentally glimpsing "black sky" if they change viewer/camera positions and forget to update accordingly. OTOH, there really aren't many usability "benefits" to having the sky beneath the horizon be black, because any scenarios where those areas do become visible still implicitly require (additional) effort to give that sky an "appropriate" surface/color.

There are some development benefits to leaving the sky beneath the horizon black in color, but they're minor at best. Further, as those areas of sky could as easily be any other arbitrary color*, the amount of additional effort required to at least make those areas match the sky color "at the horizon" is trivial. Lacking a more compelling dev reason, usability should win out, and in this case, there are decent reasons why having the color "at horizon" extend beneath that horizon offers greater usability / "safety".

*: The slight coding/computation benefit arises from those areas reducing the surface area requiring elevation-computed values. So long as those areas aren't elevation-computed beneath the horizon, the benefits exists regardless of what specific color/surface is assigned to them.

prometheus
05-03-2019, 03:19 PM
The problem with that logic is that in both reality and 3D uses, non-trivial scenarios arise where viewers can see "beneath" the horizon line, and thus need some kind of coverage.

For an example of a real-world case, when there's a depression/gorge/whatever situated right around the same distance as the horizon "terminator", it is sometimes possible (by looking "down the gorge", esp. when the gorge's "exit" is at lower elevation than its "entrance") to see sky that's technically "below the horizon". If there's no provision for showing sky below the horizon, those situations become problematic. Another real-world case is when the viewer is rising in elevation relative to the ground -- as their elevation rises (the angle between the viewer-horizon line and tangent at horizon increases), the viewer will see sky that was previously hiddden by the horizon.

Having a sudden transition to black is much more likely to cause additional work for users versus retaining that same "final color" across the entire view hemisphere beneath the "horizon", because users don't need to worry about accidentally glimpsing "black sky" if they change viewer/camera positions and forget to update accordingly. OTOH, there really aren't many usability "benefits" to having the sky beneath the horizon be black, because any scenarios where those areas do become visible still implicitly require (additional) effort to give that sky an "appropriate" surface/color.

There are some development benefits to leaving the sky beneath the horizon black in color, but they're minor at best. Further, as those areas of sky could as easily be any other arbitrary color*, the amount of additional effort required to at least make those areas match the sky color "at the horizon" is trivial. Lacking a more compelling dev reason, usability should win out, and in this case, there are decent reasons why having the color "at horizon" extend beneath that horizon offers greater usability / "safety".

*: The slight coding/computation benefit arises from those areas reducing the surface area requiring elevation-computed values. So long as those areas aren't elevation-computed beneath the horizon, the benefits exists regardless of what specific color/surface is assigned to them.

I donīt agree...with the part regarding a problem with the logic, not the rest(though your reference to "my logic" is kind of fuzzy since I made a fuzzy statement that can be interpreted in many ways)
..I think my logic is fair enough, I never said a horizon is a straight line in anyway, there are several kinds of horizons, and parts where it sort of loosing itīs term.
As for having options to not have a pure black level below the horizon, I havenīt said anything against that...as I mentioned before, and dpont has some of those options in his sunsky, additional option to the new physical sky model is welcome of course.
https://en.wikipedia.org/wiki/Horizon

Quote...
"The horizon or skyline is the apparent line that separates earth from sky, the line that divides all visible directions into two categories: those that intersect the Earth's surface, and those that do not. The true horizon is actually a theoretical line, which can only be observed when it lies on the sea surface. At many locations, this line is obscured by land, trees, buildings, mountains, etc., and the resulting intersection of earth and sky is called the visible horizon. When looking at a sea from a shore, the part of the sea closest to the horizon is called the offing.[1]

The true horizon is horizontal. It surrounds the observer and it is typically assumed to be a circle, drawn on the surface of a perfectly spherical model of the Earth. Its center is below the observer and below sea level. Its distance from the observer varies from day to day due to atmospheric refraction, which is greatly affected by weather conditions. Also, the higher the observer's eyes are from sea level, the farther away the horizon is from the observer. For instance, in standard atmospheric conditions, for an observer with eye level above sea level by 1.70 metres (5 ft 7 in), the horizon is at a distance of about 5 kilometres (3.1 mi)"

prometheus
05-04-2019, 08:12 AM
And here we go again.

Just want to make it clear that I am all for a spherical skymodel and always has been, though How I was dealing with the logic about why and how the physical sky model was implemented may have given a different point of view on it.
But for dealing with some issues Jwiede mentioned about having the camera several hundreds meters up in the sky, and also having valleys or mountains which seemingly doesnīt have a true horizon..
Letīs say we have a groundplane made at 12 km, which I usally set it up to be looks ok at the 2m camera ground leve...but raising the camera up 500m and we will have that Uggly black cut off, you could then just scale the groundplane 1000 times in layout
or make it bigger from scratch when adding it.
at that ground scale, you may raise the camera up to 6km and not having any visible black cut off at the horizon, if you want to go further it will require even larger groundplane.

At those height levels..this physical sky will loose reality and it will miss to describe the earth correctly and the visible horizon, that is the earth yielding a curved bend horizon..or more exactly the visible curved earth due to the earths spherical/eliptical shape.
.
But at lower level ..I donīt see any issues with the horizon and buildings, terrain ..mountain and valleys, those items just need to sit on ground level for starters and not going below that, I think that should cover all of the issues Jwiede mentioned that could occour otherwise