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shrox
04-23-2015, 03:03 AM
The LW one is very slow, so I try HVs, volumetric lights, background gradient color affect fog, etc.

What do you use for ground fog?

BeeVee
04-23-2015, 04:04 AM
You can also try a textured plane vibrating with motion blur.

B

prometheus
04-23-2015, 04:10 AM
You mean ground fog raymarch mode?

the ground fog standard seemīs quite fast, hereīs a sample with ground fog and realistic fog together with activated procedural texture....the raymarch is very slow though.

check screen prints vpr rendertime..0,2 sec and final render 0,5 ..depends on your cpu too of course.



127955

shrox
04-23-2015, 04:14 AM
I am on 9.6.1. It's slow for me...

prometheus
04-23-2015, 04:24 AM
I am on 9.6.1. It's slow for me...

Oops...

donīt recall how fast or slow the standard ground fog was in 9.6, in lw 11.6.3 it is quite fast, the raymarch mode, just canīt use it efficient, it almost freezes VPR if you work with that active and it is very very slow.

I donīt have a problem with speed..except the raymarch mode, I have problem getting true volumetrics or good faked ones which adapts to sun position and changes color/light accordingly when using dp_sunsky, the fog I used in the image above you can color with
gradients if used with realistic fog for instance and the use a texture in the fog color channel.

Another way is to add the sunsky atmosphere plugin in the volumetrics tab, that will give some realistic fog behavior sort of, but I donīt think that would help you in 9.6 unfortunatly.

A little of topic...
Ivé talked to denis about his sunsky plugin..there are some things I would like to see, but He seems reluctant and donīt think thereīs a point of adding it, it would include making a volumetric sunlight..and perhaps a volumetric fog atmosphere.
He thought a raymarching volumetric sunligh would be to slow or something like that, the sk_sunlight canīt be volumetric, neighter can a dome light with a sunlight softness angle...what remains to simulate a true volumetric sunlight, that is the distant light, but then you will get hard sharp shadows without the softness in the more physical sunlight models like dp_sunlight and dome light.

Michael

shrox
04-23-2015, 04:43 AM
...
Ivé talked to denis about his sunsky plugin..there are some things I would like to see, but He seems reluctant and donīt think thereīs a point of adding it, it would include making a volumetric sunlight..and perhaps a volumetric fog atmosphere.
He thought a raymarching volumetric sunligh would be to slow or something like that, the sk_sunlight canīt be volumetric, neighter can a dome light with a sunlight softness angle...what remains to simulate a true volumetric sunlight, that is the distant light, but then you will get hard sharp shadows without the softness in the more physical sunlight models like dp_sunlight and dome light.

Michael

Well darn, Denis never disappoints.

prometheus
04-23-2015, 05:14 AM
Well darn, Denis never disappoints.

well..I am disappointed he canīt implement what I asked for, but I really canīt blame him..he probably has other things to do and does provide this freely and it takes time and may also require the lw team to rewrite the volumetric handler etc, so I donīt blame him personally, more the fact that it isnīt doable at the current time..and I really think the lw team needs to do something about it foremost, I am most thankful that denis provides this.

Here you can see VPR and sunsky and when deactivating the atmosphere model to show the light scatter with and without the atmosphere.




https://www.youtube.com/watch?v=iaT5IPbN8-0

prometheus
04-23-2015, 09:32 AM
hereīs some more screenshots, itīs a lot of mix hybrid with fog color texture (windy wave) and setting the right falloff scale and position..mixed with the sunsky atmosphere and sunsky backdrop...controlling the turbidity in the sunsky backdrop affects how the sunsky atmosphere scatters light in the so called turbidity pollution...unfortunatly it is a fake hack and it doesnīt truly work perfectly if you add fog color texture, the fog color texture can only be colored from itīs own layer and doesnīt pick up any of the backdrop sunsky or atmosphere color.

Clouds is hypervoxels as usual nowadays on particles, important to have distant to camera to dissolve the clouds in distance, and important to have local gradient density in the dissolve channel too just to soften clouds...the clouds are affected slightly by the fog color..I wish it could be a truly volumetric fog that reacts accordingly to sun position/color. I usually turn down the amount of fog affecting the clouds in the cloud emitters render panel, without the fog..it will not look as nice and blended.

I think I can record this in VPR interactive session so it can be seen how the sunsky is affecting the scene when moving the sun and turning of and on some parameters, I could make the ground fog color texture stronger by increasing fog level or itīs on texture
value.

http://forums.newtek.com/attachment.php?attachmentid=127959&d=1429803089



Michael

Chrusion
04-23-2015, 11:25 AM
Shouldn't we be at Hypervoxels 7.0 or 8.0 by now? Been stuck at 3.0 for, what... over 12 years? <sigh>

prometheus
04-23-2015, 12:26 PM
Shouldn't we be at Hypervoxels 7.0 or 8.0 by now? Been stuck at 3.0 for, what... over 12 years? <sigh>


yes..that has been ranted for ages now, and yes ...it is one of the major let downs for me so to speak in lack of enhancements, unfortunatly.

shrox
04-23-2015, 12:49 PM
yes..that has been ranted for ages now, and yes ...it is one of the major let downs for me so to speak in lack of enhancements, unfortunatly.

Did you send your cotton ball?

http://forums.newtek.com/showthread.php?121381

Mr_Q
04-23-2015, 02:39 PM
You can texture fog color which allows for some cool cheats. You can use gradients for a vertical fog look. Then add some noise to it.

You can also fill a room with sprite smoke (or TFD) and light it for a blanket of ground fog effect. I have a tutorial in these forums about this I posted quite a while ago. It was aimed at better volumetric lights but would work for this too.

shrox
04-23-2015, 03:41 PM
You can texture fog color which allows for some cool cheats. You can use gradients for a vertical fog look. Then add some noise to it.

You can also fill a room with sprite smoke (or TFD) and light it for a blanket of ground fog effect. I have a tutorial in these forums about this I posted quite a while ago. It was aimed at better volumetric lights but would work for this too.

Yes, that's like what I do now. Volumetrics in general needs improvement.

prometheus
04-23-2015, 03:52 PM
You can texture fog color which allows for some cool cheats. You can use gradients for a vertical fog look. Then add some noise to it.

.

Thatīs what is in my picture above..though I didnīt make it so appearant.

jwiede
04-23-2015, 06:52 PM
Don't forget you need to dissolve/opacity in StarPro background (or faked equivalent) as sun lighting drops below twilight threshold. ;)

The stars appearing distract eyes from being too focused on precisely how the scattering/fog finally fades out, which is probably desirable.

prometheus
04-24-2015, 04:33 AM
Don't forget you need to dissolve/opacity in StarPro background (or faked equivalent) as sun lighting drops below twilight threshold. ;)

The stars appearing distract eyes from being too focused on precisely how the scattering/fog finally fades out, which is probably desirable.

Hi jwiede!

Starpro ? did we discuss that in this thread? or do you mean something else equally valid? donīt follow you here, so if thereīs something in lightwaveīs fog system or dpont sunsky that are relevant, would be nice if you can explain a little more
if you got the time:)

or did you just suggest this in case one would use starpro in conjunction with sunsky and setting the sun at itīs lowest twilight level?

jwiede
04-24-2015, 03:45 PM
Hi jwiede!

Starpro ? did we discuss that in this thread? or do you mean something else equally valid? donīt follow you here, so if thereīs something in lightwaveīs fog system or dpont sunsky that are relevant, would be nice if you can explain a little more
if you got the time:)

or did you just suggest this in case one would use starpro in conjunction with sunsky and setting the sun at itīs lowest twilight level?

More the latter. Without stars becoming visible in sky as light fades, the viewer will focus on the source of the fading light, which isn't ideal when you've got lit background / colored fog / etc and ability to bring them all (separately) through twilight in a realistic manner is... difficult. I was suggesting that by using Maas StarPro (http://www.maasdigital.com/starpro/) (or alternate approach) to add starry backdrop you can ramp up while the sun light / sky light / fog color fade replicating twilight and beyond, you can draw visual attention away from focusing on potential inconsistencies between sky/sun/fog during the fade.

Hope that's bit clearer?

shrox
04-24-2015, 03:59 PM
Don't forget you need to dissolve/opacity in StarPro background (or faked equivalent) as sun lighting drops below twilight threshold. ;)

The stars appearing distract eyes from being too focused on precisely how the scattering/fog finally fades out, which is probably desirable.

I have a gradient map on the stars object to simulate that.

prometheus
04-24-2015, 06:43 PM
I havenīt really tried portraiting the twilight with stars showing up...need to study that a bit more in reality first I reckon..then test some stuff.

I am more concerned about issues with Lightwave and sunsky for example where we donīt have an accurate fog model to follow with sunsky, slight haze and light scatter, but no Real fog as I see it, and the lightwave realistic fog do not react in conjunction to the sunsky system in accurate way, it can look good when manually tweaking it, but changing the suns pitch location...and the fog illumination is the same and so is the color until tweaked manually, the fog can blend hypervoxels cloud in nicely with sunsky at a certain point, but moving the sun to twilight level and you still have the fog layer affecting the clouds and thus they look completly wrong, clouds often turns dark purple at that stage and occasionally also highlighted in gold orange at the clouds edges.

I love vueīs atmosphere engine for itīs ability to simulate this pretty nicely along with itīs volumetric fog, I just wish we could have something similar for lightwave...and no, ozone doesnīt do it for me, ogo taiki could if it were faster and with better simpler ui to setup quality and the spectral sky.

prometheus
06-06-2015, 03:10 PM
I got some quite nice whispy misty fog on transparency planes, making use of surface thickness gradients in transparency and a bump gradient, the bump gradient will use whatever procedural texture I put in the bump channel for transperancy, and I also have that gradient in luminosity channel to, and with adding suncolor spot modifier, it will look quite nice when changing sun pitch, will try and record a little session tomorrow perhaps and put on youtube.