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View Full Version : sky tracer freakin' useless....



jin choung
06-23-2003, 10:07 PM
well, i thought skytracer was a cool little secret weapon in my arsenal that i could whip out and reliably kick *** upon need.

well, trying to create sky domes for our latest racing game and have been r&ding ways to get quick, reliable, great looking skies.

alas, skytracer is [email protected]#$ing USELESS!!!

waaaaaaaaaaay too finicky with controls that sound technical but doesn't give any good intuitive way to adjust the look!

the range of acceptable looking results is also very small.

also, HUGE problem with the EXPOSURE of clouds!!! MOST - MOST of the skies end up with vast expanses of overexposed white with black areas that are completely devoid of detail.

also, you end up with a great deal of clouds bunching up near the horizon to create great aliased strips of cloud as it fades off into the horizon.

it may be tichnically realistic but why don't i EVER see this in the real world?!

and how the [email protected]#$ can i get rid of it?! there seems to be no real solution.

i am sorry to say that sky tracer is complete crap when you have to make a sky and the sky isn't just a backdrop that you hope that no one really notices.

hell, even the $69 app here has a cloud maker that's FAR easier to use and produces much better results!

www.texturemaker.com

ekki's skygen is pretty good but also tends to produce clouds that are not exposed properly with not a great deal of detail.

my first skydome i just edited NOISE to make clouds and came up with better stuff.

ack.

jin

Lamont
06-23-2003, 11:03 PM
Before you kill someone Jin,

Here is what I did with Eki's... this is an old one sorry 'bout that. :)But the one I made later I removed the sun and a few other things... then took it into photoshop and did some stuff.

It came out very nice in our simulator...

Lamont
06-23-2003, 11:05 PM
Yeah, I end up modding the skies I render anyways... they never look right. Like you said, the clouds look overexsposed.

Then again, they are high altitude clouds, there's volumetric coulds closer to the ground.

jin choung
06-23-2003, 11:50 PM
hey lamont,

:) yah, it pisses me off no end having to r&d!!! argh! to spend a lot of time (okay 3 days) and come up blank - at least with your weapon of choice....

argh!

nice results ya got.

i was putting up my results from skytracer against photos and it just did not look right. i wanted to use sky tracer to just make a sky - not have to finagle it to death later in photoshop. in that case, it's easier to just use texture world to generate perlin noise and use that as a custom brush in photoshop.

anyway, you should take a look at texture maker.

fewer controls, better names, better results - quicker.

if you don't need to fly through a cloud, if all you're doing are skydomes, you should check out texture maker.

i personally haven't purchased it yet (noodling with the demo) but if i end up having to do more skies, i'm most definitely gonna go for it.

jin

Lamont
06-24-2003, 12:06 AM
Yeah, it took about 5 hours to make a dusk sky.:(

When I tried skytracer (I too was like "Here is my secret weapon!!") I was disapointed.. it took TOO much work to get minimal results. And since I am not a meteorologist, the settings made little sense.

Post your results with that app, and if it's as easy as you say, then I'll get it. 70 buck's not bad at all. I know I'll have to make a sky soon... like in a couple of weeks.

Lamont
06-24-2003, 12:08 AM
Skytracer never looked right, but you can get some neat-o stuff out of it.. too bad it's not what I need at the moment.

Oh dude!! Remember that plug-in by the guy who did OGO Hikari? I want to try that one!!

Mylenium
06-24-2003, 12:23 AM
Hehe guys,

Me wonders why you didn't try Ozone. It's dead fast, has tons of beautiful presets and in the new version can even be animated. I don't know much about gaming related issues but if you are just after a beautiful sky this one is perfect.

Mylenium

jin choung
06-24-2003, 01:12 AM
money.

ozone may be great but it's not in my price range. like i said, you guys should check out texture maker. for all it does (seamless textures, perspective correction, etc), it's a steal for $69.

jin

jin choung
06-24-2003, 01:15 AM
oh and lamont,

it won't let me export any images greater than 255 but it won't do it justice.

download the demo (very small) and try it out. you won't regret it. it's also primarily a seamless texture maker (like a bitmap version of dark tree) and will let you do texture correction, seamless animation cycles, etc.... lots of good stuff for games.

got the link to it from flay.com. it was a GOOOD call!

jin

kevman3d
06-24-2003, 03:29 AM
Originally posted by Lamont
Oh dude!! Remember that plug-in by the guy who did OGO Hikari? I want to try that one!!

Heheh, that would be 'Taiki' - Well, lets hope he's optimised it - If you thought skytracer was slow, well, hold onto ya hats for the Taiki express! :)

It does create some outstanding results - I was impressed (one example flys the camera from the ground, up through the clouds and into space to finally view the entire planet), though I wouldn't want to ever use it in an animation at the speed it takes to render them! :)

TyVole
06-24-2003, 06:18 AM
I'm wondering if WorldBuilder Pro, the version that's about to be released free with the next issue of Digit, is capable of creating better skies.

Has anyone used it for this?

mattclary
06-24-2003, 07:33 AM
Kinda weird seeing you go off like that Jin, not expected. I agree with you though, Skytracer is one of my least favorite items in LightWave. Can usually get better and more predictable results by texturing a dome. I've pretty much just blamed my ignorance up until now, but I see it's not just me.

colkai
06-24-2003, 09:00 AM
I'm wondering if WorldBuilder Pro, the version that's about to be released free with the next issue of Digit, is capable of creating better skies.

Fair to say I'll be picking up a copy anyhow - Some really neat software coming out on Magazines these days! :D

Lamont
06-24-2003, 09:30 AM
Render times usaually aren't important because the final output is twice my target res (usually 512x512), and I have a monster machine in my office if I need to use it.

But I am gonna download that Texture Maker app right now and see how it runs. The fact that it can make tiled textures rules...

Mattoo
06-25-2003, 08:52 AM
Originally posted by jin choung
well, i thought skytracer was a cool little secret weapon in my arsenal that i could whip out and reliably kick *** upon need.
...etc

jin

Have you got VIPER open at the same time?

VIPER is actually really good with SkyTracer, takes loads of time out of the guess work since it'll show instant(ish) feedback. Remember just to F9 once and then VIPER will work.

Old Skytracer used to be rubbish, this one is much better, I can actually get results with it that don't look like a fractal noise cloudscape.

Roundpixel
06-25-2003, 09:16 AM
If skies is what you´re after, then try Terragen.

http://www.planetside.co.uk/


JC

kevman3d
06-26-2003, 04:50 AM
Yup, Terragen is pretty cool for making skys! It even traces atmospherics pretty well too - Great for those 'finger of god' effects!

Used it a couple of times for skys... And add to that its FREE!

Heres a tiny example of TG sky with beams coming through the clouds I showed at a LWUG over a year ago...

ericsmith
06-26-2003, 02:16 PM
speaking of terragen, is there an easy way of exporting a sky as an environmental image map? or do you have to render out pieces and assemble them in photoshop to get a complete 360 degree image?

Eric

riki
06-26-2003, 11:41 PM
Personally I think hand painted skies look the best. I've seen a few good tuts

http://gallery.artofgregmartin.com/tuts_arts/riven_walkthrough.html
http://www.optidigit.com/stevens/cloudtut.html

Roundpixel
06-27-2003, 02:49 AM
Originally posted by ericsmith
speaking of terragen, is there an easy way of exporting a sky as an environmental image map? or do you have to render out pieces and assemble them in photoshop to get a complete 360 degree image?

Eric

You´d like to check the following url:
http://www.rna.hr/tutorial01/

cheers
JC

Hervé
06-27-2003, 02:58 AM
Hello Jin, do you know where I could find Texture Maker... didnt found it on Flay....

Thanks, Hervé

Stranahan
06-27-2003, 09:09 AM
Mattoo made the point...

Use VIPER.

and I might add..

Use Presets...


SkyTracer works with both Viper and the Preset Window.

If you aren't using it that way, it would suck something awful. And it's not obvious that it works with those features of LightWave.

jin choung
06-27-2003, 11:37 AM
nope,

i'm using both viper and the presets.

it would be nice if the presets were usable!

but they're not. it might pass for acceptability at a quick glance but it absolutely does not pass for muster on close inspection. also, the problem with the exposure of the clouds is evident no matter what kind of settings or clouds you use.

just my opinion but if it works at all, it is far too arcane and finicky to be a truly useful tool in production.

i mean geez, the PRESETS don't look good!

jin

ericsmith
06-27-2003, 12:27 PM
O.K., here's some tips based on your original complaints...

1. exposure- you can get good exposure simply by finding the right balance between "luminosity" and "opacity" in the main cloud tabs. also, remember that: A. you can use any light in your scene as a sun. This is often easier to control the the default SKT sun. and B. the brightness and color of the light used for the sun will affect exposure as well, and C. the "contrast" setting in the main cloud tab usually defaults way too high. take it down to around 40% and see what happens.

2. clouds bunching up on the horizon- if you set the x and z falloff on the cloud texture to something like 2%, it takes care of this problem nicely - on a side note, procedural textures are the foundation of clouds in skytracer. If you don't have a firm grasp on how to control them, you won't get very far.

3. removing skytracer from a scene- go to the backdrop tab under effects and you will see skytracer listed under environments. select it and remove it just like any other plugin.

The fact is, skytracer IS capable of some pretty good looking skies, but it takes a certain level of mastery to really get a handle on it. I've found hypervoxels, and to a lesser extent, sasquatch and procedural textures to be the same way. But if isolate each variable and spend enough time to figure out what it really does, pretty soon you will have a good handle on the whole thing and will be able to crank out good skies fairly quickly.

On the other hand, I did try out terragen's cloud generator, and right off the bat, the skies and clouds look smoother and more natural. So maybe it's a better solution. I'm still wondering how easy it is to generate a sky in terragen and get mapped onto a sphere in a LW scene. I checked out the tutorial roundpixel mentioned, but that seemed to be more focused on HDRI rendering than just creating an image map for a background texture.

Eric

jin choung
06-27-2003, 12:33 PM
well,

if skytracer is usable, it would be nice if the PRESETS contained skies that represented the pinnacle of what is possible.

and if the results are somewhere right about where the presets are, it's still not an option.

jin

Hervé
06-27-2003, 11:16 PM
Hello Jin, do you know where I could find Texture Maker... didnt found it on Flay....

Thanks, Hervé

Lamont
06-27-2003, 11:17 PM
Read the very first post of this topic. :)

Hervé
06-28-2003, 06:20 AM
He he thanks Lamont...

Flashfire|REAL
06-28-2003, 02:49 PM
I flat out disagree that Skytracer is useless... its very poorly documented, and once you have an understanding of the hows and whys things are done within it's code, you can churn out some very nice skies...

I have created documentation 10x's that of Newtek's for Skytracer2 that will appear in my upcoming Landscapes and Lightwave tutorial... see more here:

http://www.lwg3d.com/forums/showthread.php?threadid=11548

Be warned... there is 36 pages, each page contained 25 posts, for a total of 891 replies...

Also, I have fully documented OGO Taiki, which is included in this tutorial as well...

The tutorial is undergoing a beta period right now, and should be available (chapters 1 - 8) in about 3 weeks...

Cheers!

Lamont
06-28-2003, 02:53 PM
How long did it take you?

Flashfire|REAL
06-28-2003, 03:02 PM
The link to the thread isn't the tutorial itself... its to the ongoing development of the tutorial for those who'd like to see it being made... all told, I've invested 300+ hours into making 8 chapters for this tutorial so far (which will be 16+ chapters once complete). The first 8 chapters contain 51 progressive sections, one leading to the next and so on... so in essence you have 51 full length tutorials taking you from planning to construction to texturing to adding skies and finally water within the span of these chapters. Currently, the zip file archive for the first 8 chapters is 155 megs, with an estimated 160-200 more megabytes to add to it for the final chapters and addendums.

The final 8 chapters are currently in planning and R&D; nothing has been put to HTML yet, so I don't see them being complete until late September anyways... although I have been posting images of work that will be featured in those chapters lately... :)

Cheers!

Lamont
06-28-2003, 03:04 PM
No, I mean, how long would it take you to make a decent sky w/skytracer? I know if it's longer than 3-4 hours, it's not worth it for me.

Mattoo
06-28-2003, 03:08 PM
I quite agree that it is no way useless.

It's only in the last six months that I have needed some skies and my first thought was to dismiss SkyTracer.
However, I saw that it had been updated since I last looked at it and that the presets were pretty good but not what I wanted. So I battled away with little success, got frustrated and was about to give up.

But then I calmed myself and went about it logically finding out what each function did. Eventually I got what I wanted and feel much better for understanding it now.

Flashfire|REAL
06-28-2003, 03:14 PM
Originally posted by Lamont
No, I mean, how long would it take you to make a decent sky w/skytracer? I know if it's longer than 3-4 hours, it's not worth it for me. LoL... sorry... :(

Well, the render time depends on the output size really... so it's only a matter of tweaking ST2 and the Sunspot plugin to give you the look you're after... adding radiosity to the mix, certainly, will increase render times.

However, you can cut the time it takes to make a good looking sky almost to 1/8 or more of the usual time, once you understand how the scattering algorithms are used in the plugin; of which I am estimating based on experimentation, that all 3 forms of atmospheric types are present. Here's an excerpt from my tutorial, explaining scattering:

"Rayleigh scattering, Mie scattering, and non-selective scattering.

Rayleigh scattering mainly consists of scattering from atmospheric gases. This occurs when the particles causing the scattering are smaller in size than the wavelengths of radiation in contact with them. This type of scattering is therefore wavelength dependent. As the wavelength decreases, the amount of scattering increases. Because of Rayleigh scattering, the sky appears blue. This is because blue light is scattered around four times as much as red light, and UV light is scattered about 16 times as much as red light.

Mie scattering is caused by pollen, dust, smoke, water droplets, and other particles in the lower portion of the atmosphere. It occurs when the particles causing the scattering are larger than the wavelengths of radiation in contact with them. This type of scattering is what makes clouds appear white.

The last type of scattering is non-selective scattering. It occurs in the lower portion of the atmosphere when the particles are much larger than the incident radiation. This type of scattering is not wavelength dependent and is the primary cause of haze."

Now... this knowledge in conjunction will other aspects of the atmosphere's properties can go a long way in helping you to set up the sky to look good, rather than the run of the mill...

Cheers!

Lamont
06-28-2003, 03:15 PM
Sweet Sky in short time = useless
Sweet Sky after a long *** time of tweaking = cool

I know what can be done with Sky tracer, unfortunately, I don't have the time to endlessly tweak settings. When a bunch can be consolidated or removed.

Flashfire|REAL
06-28-2003, 03:16 PM
Now this, we at least agree upon... lol! :D

RyanRaner
06-29-2003, 06:51 AM
I don't think its useless, its capable and has potential, but its just underdeveloped.

I've been messing with Skytracer, seeing if there is a possibility of using it in a PC game that I'm working on. The thing with PC games compared to ones played on a TV is the high resolutions of monitors make it too easy for people to see that it isn't photorealistic. I think I have yet to see a good sky in a PC game.

Ive got some decentish results so far, but my main beefs with it from a game devs point of view are things like:

No rendered image for the bottom of a skybox (Ok for animations, but in PC game levels where geometry is limited you need one)
Weird visual errors at times on edges of the low altitude clouds when the high altitude clouds pass behind them.
Bakes the sky only. We can't have it bake geometry to have background enviroment, or to do something like add a moon and stars to a night sky without having to edit the warped images in photoshop and try to make it look right.
Takes too long to get to the results needed.

jin choung
06-29-2003, 08:56 PM
well i'll believe it when i see a totally realistic, properly exposed sky, with good cloud detail from ST with no photoshop tweaking.

heck, if it were possible, i'd imagine that they'd ship it as a preset don't you?

hey and if you can include a preset with your tutorial, that would be great first hand proof.

but as it is so far, you get results that are acceptable in passing, can draw a bunch of ooohs and aaahs at conventions but nothing really solid and tight for real world production use.

jin

lone
07-04-2003, 11:20 AM
ERICSMITH's tip about lowering the contrast does help - as for the bunching up on the horizon thing, i usually just rotate the horizontal 10 - 20 degrees.

fabmedia
07-15-2003, 07:52 AM
Okay, so to jump into the old conversation, how do you create a HDR image from using Erkki's SkyGen? Or is there a simple workaround for something close?

Arlen

richpr
07-15-2003, 07:39 PM
@fabmedia
Read around some of these topics (HDRI, sky globes and other interesting realism... eh here (http://www.debevec.org/) Some stuff for Lightwave as well and usable with a little reading/tweaking...

fabmedia
07-15-2003, 08:08 PM
uh-oh... looks like I have to invest in a PC if I expect to create my own HDRI.

Know of any Mac based stuff?

A

Halsu
07-26-2003, 06:43 AM
Originally posted by fabmedia
Okay, so to jump into the old conversation, how do you create a HDR image from using Erkki's SkyGen? Or is there a simple workaround for something close?

Arlen

Just render a frame and save it in a HDR image format. Done.

...okay, there's slightly more to it ;-)

In the sky, there's usually not much that actually needs the extra range of HDRI - i.e. in SkyGen, the only things that are above 100% white are usually the sun, and maybe some highlights in the clouds - but that's really how the sky is, also in real life. There's not that big differences in luminosity (except for the sun, naturally).

In a typical SkyGen scene, even the sun's brightness is only something like 150%, instead of much higher contrast in real life. But, if you wish, you can adjust the sun opacity slider (or envelope) to get brighter sun.

You can use RefGen (also part of my PlugPak) to create a spherical panorama, as well as up, down, left, right, back and front renders of your scene. If the scene only has SkyGen, the result is a sky wrap image. But the scene can just as well have objects in it, resulting in an environmental 360 degree panorama of your entire scene (in HDRI if desired).

Here's some SkyGen/RefGen examples... (http://www.kolumbus.fi/erkki.halkka/plugpak/PlugPak_Gallery_index.html)

Some more (http://groups.yahoo.com/group/PlugPak/files/Movies/)

nuclearchutney
07-26-2003, 11:23 AM
Originally posted by fabmedia
uh-oh... looks like I have to invest in a PC if I expect to create my own HDRI.

Know of any Mac based stuff?

A

Not at all. There is a program like HDRShop. Its called Photosphere.
http://www.anyhere.com/

nuclearchutney
07-26-2003, 11:26 AM
And here is a link to a tutorial on how to generate light probes from within Lightwave

http://www.rna.hr/tutorial01/default.htm

Karmacop
07-26-2003, 08:49 PM
When I go to http://www.lwg3d.com/forums/showthread.php?threadid=11548 it says the thread cannot be found. Does anyone have the correct link for it or a mirror? Someone mentioned it on page 2 of this thread ..

Steve Warner
07-27-2003, 12:20 AM
For what it's worth, Savinoff's sky scenes (http://www.savinoff.com/home/?chapter=extras&part=scenes) have some of the best looking skies I've seen in LW - without using SkyTracer. They're easy to set up, infinitely customizable, they work with VIPER, and they're free. Eki uses a similar technique in his plug-pak.

Cheers!

Steve

Original1
07-27-2003, 05:48 AM
One of the really neat playthings I have found this week

http://cinepaint.sourceforge.net/


Why is it cool?

Combine it with the OpenEXR loaders and you can pull open HDR, flx and other High Dynamic range images into lightwave save them from the image editor as an OpenEXR or any other floating point formats that CinePaint (film gimp) if you are a Mac Based person and edit the sucker.

Now back to the subject of Gins issue with Skytracer.

One of the reasons certain areas of a skytrace might be overexposed is the floating point format in which they are stored,
I suppose you tried tweaking HDR expose or multiple layers in Cinepaint exposure tweaked with layers blended together and then flattened to a final image.

I do agree however that Skytracer (no most of Lightwave is woefully documented) as good as the community and the Tutorials are, you should not have to depend on third party advice on how to get the best out of your tools.

Original1
07-27-2003, 06:25 AM
Originally posted by nuclearchutney
Not at all. There is a program like HDRShop. Its called Photosphere.
http://www.anyhere.com/


Theres a mac version of Cinepaint

http://cinepaint.sourceforge.net/

Its free at the moment it does not seem to open HDR, but you can use lightwave to open the HDR save it to something that Cinepaint can open edit in up to 32 bits per channel and then bring it back in to lightwave

DoF
07-28-2003, 06:29 AM
"sky tracer freakin' useless....you end up with a great deal of clouds bunching up near the horizon to create great aliased strips of cloud as it fades off into the horizon. "

Use the z falloff control in the texture editor initiated from Skytracer 2

Actually, if you're prepared to tweak, [make sure you have Viper open from Skytracer 2] you can achieve superbly realistic skies.

:)

lone
08-01-2003, 10:42 AM
DOF - don't know any good settings for storm clouds, do you? i'm not having much luck.

KenM
08-01-2003, 11:46 AM
Tweaking led to better 'cloud control', this image took only five minutes of tweaking from opening Skytracer 2. It's better than the starting point and can be tweaked further..

I recall from somewhere on the forums to raise the turbulence texture's frequencies and small power.

This image used 11 octaves and a small power of .75. "Volumetric Rendering" and "Texture Shadows" need to be on. "Contrast" and the type of texture you use make a big difference in the look of the clouds, and using unrelated procedurals like 'underwater' create interesting results too.