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Graphx
01-26-2009, 09:00 AM
How do you setup a scene to show that you were flying through clouds. I think you should be able to do something like that with hypervoxels but I don't know how to set up right.

stevecullum
01-26-2009, 02:47 PM
Just add an HV volumetric to a couple of nulls and then adjust the setting to be more cloud like. Then pass the camera through them.

3DGFXStudios
01-26-2009, 03:49 PM
You can also use sprites and use them on points. That renders faster...

Iaian7
01-28-2009, 02:18 PM
Another option is to use multi-layered geometry with procedural textures driving transparency... oldest trick in the book, but it can work, and work well. Combining that (20+ layers and a lot of nodal texturing) with a little After Effects, and I've been able to create volumetric-like cloud flythroughs with much better results than hypervoxels (which I've never gotten to look good). I'd post a link to my process, but that tutorial was never really finished... hmm... if I get time this week, maybe I'll try to whip it together.

nikfaulkner
01-29-2009, 12:26 AM
that sounds very interesting iaian7.

i look forward to it :)

toeknee
01-30-2009, 11:27 AM
Hey Graphx
I agree with the idea of points and Hypervoxels but what I did for a resent project that worked great was to use the plugin Dynamite. I just needed the free plugin and I would use it to make images of cloulds. Then I expoted the Image in an image format that used an alpha channel. I then made some polygons and maped them them. The cool thing about this is that Dynamit is great for making clouldes and when you map them to a polygon you can animate the polygon and have a very reallistinc looking clould scene. if I find the base scene for dynamite I will post it later. Good luck.

stevecullum
01-30-2009, 11:55 AM
You can always bake the hypervoxels to make them speedy to render :)

3djock
01-30-2009, 01:17 PM
Another option is to use multi-layered geometry with procedural textures driving transparency... oldest trick in the book, but it can work, and work well. Combining that (20+ layers and a lot of nodal texturing) with a little After Effects, and I've been able to create volumetric-like cloud flythroughs with much better results than hypervoxels (which I've never gotten to look good). I'd post a link to my process, but that tutorial was never really finished... hmm... if I get time this week, maybe I'll try to whip it together.

Sounds interesting just what I'am looking for also.

JBT27
02-06-2009, 06:12 AM
Another option is to use multi-layered geometry with procedural textures driving transparency... oldest trick in the book, but it can work, and work well. Combining that (20+ layers and a lot of nodal texturing) with a little After Effects, and I've been able to create volumetric-like cloud flythroughs with much better results than hypervoxels (which I've never gotten to look good). I'd post a link to my process, but that tutorial was never really finished... hmm... if I get time this week, maybe I'll try to whip it together.

I know it's an infernal cheek.....but if you can do that tut, or a bit of it, I'd be very grateful. I get the gist of what it must require to do it that way, but if you've got results comparable, or actually better, than HVs, I'm all ears :D

Julian.

Iaian7
02-06-2009, 12:46 PM
Haha, no, it's fine! I'm sorry it's taking so long to get the tutorial done... I'm not very good at writing them, and life is pretty tumultuous right now. Till I get something more posted tonight, I'm attaching an example from a project I did last year.

JBT27
02-06-2009, 01:16 PM
Good grief, that is superb, and just the kind of thing I need to get me out of the HV hell I've been wallowing in all day :D

Seriously, some pointers would be great, even hints if not a full tut.....

Really impressed by those clouds!

Julian.

prometheus
02-06-2009, 04:58 PM
Those clouds are impressive Iaian7!

so those are only geometry and procedurals on transparency that is?

But how would it stand up against objects inside the cloud volume and fly throughs?

It would be nice to see an animated sequence if you have?

Michael

prometheus
02-06-2009, 05:41 PM
hereīs a little sample ..of hypervoxels clouds a particle emitter and a simple turbulence hypertexture, shading set to good quality, no volumetric
shadows or texture shadows..

illumination model beer(should use rayleigh for more realistic results)
lumunosity has a y-distance to particle gradient in additive mode over
another gradient set to local density.

on the thickness channel thereīs also a gradient set to distance to object and emitter as choosen object.

one of the images has 70 particles and the other 100 particles.
of course we can always use sprayed points aswell.
But setting this up goes very fast...the rendertime takes a little longer thou.

then thereīs a whole other story of getting nice background air and air properties to interact with the hypervoxels, not so easy to do..so I settled for a simple blue color:)

otherwise..ogo taiki or ozone could handle that nicely.

Michael

nikfaulkner
02-06-2009, 11:24 PM
wow Iaian7, they look great

cant wait for some more info (or a little demo scene if its easier than writing a tutorial :) )

hopefully see more soon

n.

JBT27
02-07-2009, 02:29 AM
hereīs a little sample ..of hypervoxels clouds a particle emitter and a simple turbulence hypertexture, shading set to good quality, no volumetric
shadows or texture shadows..

illumination model beer(should use rayleigh for more realistic results)
lumunosity has a y-distance to particle gradient in additive mode over
another gradient set to local density.

on the thickness channel thereīs also a gradient set to distance to object and emitter as choosen object.

one of the images has 70 particles and the other 100 particles.
of course we can always use sprayed points aswell.
But setting this up goes very fast...the rendertime takes a little longer thou.

then thereīs a whole other story of getting nice background air and air properties to interact with the hypervoxels, not so easy to do..so I settled for a simple blue color:)

otherwise..ogo taiki or ozone could handle that nicely.

Michael

Those are nice!

Bit of a debate really which is best, though I suspect both have their place.

I've been getting some serious popping with my thin-cloud flythrough, which I suspect is the old problem of the camera being too close to the HVs - desperately searching around to find detail on that, as I cannot finish this shot until I do.....hence wanting other ways to achieve this.

How you fly through HV clouds without getting too close to the HVs I haven't figured yet :)

I tried some random geometry with transparency driven by procedurals - getting potential results with alot of spherical objects, but still not losing the ghosted appearance of the original objects.

Julian.

Iaian7
02-07-2009, 03:33 AM
Ok, at long last... the fake volumetric cloud tutorial is posted! (http://iaian7.com/lightwave/FakingVolumetricClouds) And yes... the technique is great in some situations, horrible in others. Same as any trick, there's a time and place for pretty much anything. I seem to use it rather often, though, and hope it helps someone else out too.

Anyway, it's 5:30 in the morning, and I haven't slept yet... so I make no promises as to the lucidity or veracity of my documentation! It maybe very well be way too basic for most people, don't know. Hopefully I'll get it edited a bit sometime... but we'll see. A lot of other stuff on my plate this weekend. First up is bed... :D

nikfaulkner
02-07-2009, 03:35 AM
wow thanks iaian7,

i'll check it out now :)

sleep well


n.

JBT27
02-07-2009, 05:27 AM
That's a great tutorial - thanks very much indeed :thumbsup:

It's also a bit of a wake-up call as I've been dumb enough to completely forget how effective that can be!

I did a cloud flythrough for a film about seven years ago, where I effectively flew the camera (in Maya) towards paintings of clouds, on black, partly done with HVs. Rendered each plate separately then did all the comp in AE - worked a treat.

But the procedural effects are really nice, and the stacked layers - I'm a big fan of comp to be honest, especially for stuff like this, so there's a wealth of ideas and potential here.

And it reminds me not to get bogged down with volumetrics all the time ..... :D

Thanks again - a big help!

Julian.

AbnRanger
02-07-2009, 07:21 PM
An alternative method would be to try and get as decent a look as you can get with you HV's (or Dynamite), with settings that give you a moderate compromise on speed/accuracy/quality. Then render out the clouds separately from the background. In your compositor, make a few copies of the cloud renders, and set the top one to "Screen" or Soft Light blending mode. Add a heavy dose of blur to that layer and offset it slightly so that it's not sitting directly over the top of the same pixels.
Adjust the opacity as needed to get that wispy look to the clouds (that look is hard to get in any volumetric effects engine).

You can take the middle layer and play with the blending modes a bit. Maybe a "Multiply"....offset it a smidge as well...adjust the opacity....maybe add a hint of turbulent noise to it. This should give the clouds both a thick and detailed look, yet have some areas that are soft and wispy.

BigHache
02-10-2009, 11:14 PM
iaian7 wow, nice job on the tutorial. :2guns:

I've bookmarked and will be referencing that in the near future.

HowardM
02-11-2009, 09:21 AM
How you fly through HV clouds without getting too close to the HVs I haven't figured yet :)
Julian.

Use a Gradient, Distance to Null attached to Cam and fade them out as they get close to the cam.... ooooold method.
;)

3DGFXStudios
02-11-2009, 09:38 AM
You can always bake the hypervoxels to make them speedy to render :)

How do you bake hypervoxels? :stumped:

Red_Oddity
02-11-2009, 10:02 AM
With the Bake Object button found under the Basic tab of the Shading tab in your Hyper Voxels window.

You learn something new everyday, don't you Niels? ;p

JBT27
02-11-2009, 12:02 PM
Use a Gradient, Distance to Null attached to Cam and fade them out as they get close to the cam.... ooooold method.
;)

..... so it is :D ..... sometimes I think way too hard about these things.

However, in this case, I found alot of the popping was in the middle-distance, and only happened about halfway into the shot - it worked a treat up until then.

In the end, the planes method worked very well and I got a better looking effect alot quicker, well in this case anyway.

A depressing thread.....reminding me how crap my memory has become :D

Julian.

JohnMarchant
02-12-2009, 12:49 PM
Here is a quick test i did. Well done on the tutorial and examples Iaian7, really liked the look after i played around with the shadows and stuff. Going to try a little animation to see how well it looks,

Regards, John

JohnMarchant
02-12-2009, 12:52 PM
Of course it would be nice to displace the clouds as you fly through, but thats probably another problem for another day, or maybe Core ;););)

JohnMarchant
02-13-2009, 04:26 AM
Here is a small 30 frame test of the animation. Quality not so good but just to get an idea. Took 6 hours to render these frames as a seqnece then put them together. Sorry about the rar file but did not want to loose any more quality than i had to.

BigHache
02-14-2009, 12:46 AM
Nice test. Lots of potential. :thumbsup:

Wopmay
02-14-2009, 08:03 PM
Great tutorial. Thanks!

yaschan
02-24-2009, 04:07 PM
Fantastic tutorial Iaian7! I think this method is very good for various of uses. I was really surprised how great these clouds look.
Thank you!

Iaian7
02-24-2009, 05:17 PM
Thanks! Glad you all like it. :D

3djock
03-03-2009, 01:05 PM
Great idea and tutorial ..

archijam
03-05-2009, 02:39 AM
Missed this thread, and now I know why .. you posted that tutorial on my birthday, perfect timing ;) ..

I would be interested to try this in combination with HD instance ... will get back to you on that :thumbsup: ...

Fadlabi
03-05-2009, 05:37 AM
aian7, link can't work.

Iaian7
03-10-2009, 08:37 AM
aian7, link can't work.

This one? Faking Volumetric Clouds in Lightwave (http://iaian7.com/lightwave/FakingVolumetricClouds)

Seems to be working fine for me... :stumped:

dnch
03-12-2009, 06:45 AM
hey Iaian7,
great technique you got there...
too bad it does not work with fprime (cause of transluency node).. because it renders kind of slow..

Mr Rid
03-23-2009, 05:28 PM
How do you bake hypervoxels? :stumped:

I dont know if anything has changed since I tried baking HVs in v7.5 days but it was yet another incomplete tool. There was a limit in the resolution size. You could only bake one object with HV applied. It worked fine on a single localized cloud (am not sure, but the pixels may have shown up in a flythru), but if you baked a sky of clouds then they all became too pixelated due the limited resolution. The one baked cloud looked different than the non-baked clouds, and baking and rendering individual clouds was impractical. Gave up on baking for a flythru of more than one cloud.

toby
06-27-2009, 10:45 PM
Awesome technique and tutorial Iaian7, thanks mucho!

nikfaulkner
06-29-2009, 10:35 AM
anybody any pointers on how to use an image instaed of a gradient?

so i can have specific shaped clouds?

ta

n.

Larry_g1s
07-01-2009, 10:44 AM
Just came across this John...very nice tech. I'm looking forward to trying it out. I pray things are going well for you.

thekho
07-03-2009, 10:21 PM
Awesome tutorials especially interesting nodes! Faster than HV!! Thanks for your excellent tips, Iaian7 :thumbsup:

Iaian7
07-06-2009, 09:27 PM
Thanks everyone! Glad you like the little post on my blog. :D


anybody any pointers on how to use an image instaed of a gradient?
so i can have specific shaped clouds?
ta
n.

You want to replace or augment the gradient's role - setting up variations between white and black, on top of which the texture nodes can create detail and procedural shapes. You can apply images between the base gradient and the rest of the nodes, or base everything off images anyway. The easiest way is to set up a simple z-axis project with an image in the desired shape. Try it out, and you'll begin to get a feel for how blurry or sharp the image should be (typically, pretty blurry, but it depends on how you've tweaked your nodes, of course!).

If you're not getting enough of a cloud shape, reduce the contrast and brightness of your texture nodes. You want to add enough procedural noise to make the clouds look naturally random, but not enough to eat away at the desired shape.

trang
09-15-2010, 08:24 PM
hi Iaian7,
i saw your tutorial for vol clouds. is it possible to dwnload the images individually so i can further study your tut offline? seems i cannot save the thumbnail images as larger pictures.
let me knw thank you.

Iaian7
09-16-2010, 02:59 PM
hi Iaian7,
i saw your tutorial for vol clouds. is it possible to dwnload the images individually so i can further study your tut offline? seems i cannot save the thumbnail images as larger pictures.
let me knw thank you.

The overlay script I use (mediaboxAdvanced (http://iaian7.com/webcode/mediaboxAdvanced)) blocks downloading of images. I know that may be kinda silly, but I don't watermark my images, so it's a tiny bit of discouragement for those who would rip images off my blog (I totally get why you want to though, so no ill will :thumbsup:). The easiest workaround is to open the page in Opera, which ignores contextual click blocking, then just right click the thumbnail and download the linked file (all thumbnails point to larger images).

trang
09-17-2010, 07:50 PM
opera..hmm this cannot be done in firefox then?

Mr Rid
09-17-2010, 11:39 PM
You can also hit 'Print Screen' button (I dont know how Macs work) and paste into an image viewer, PShop (Ctrl-N, ok, Ctrl-V), crop, etc. Even paste in Wordpad.

prometheus
09-18-2010, 07:29 AM
with respect for iaian7, its also very simple to simple left mouse button klick on the small images, but keep the mouse button in and drag the image to the webbrowsers adress bar, that will open an new window and right klicking save will be possible.

Michael

Iaian7
09-20-2010, 09:47 AM
Mr Rid - On a mac, command+shift+3 or 4 will save screenshots as .png files to the desktop (the former captures the entire screen, the latter captures a portion, or with the press of the spacebar, specific windows).

Prometheus - I'd never tried that, thanks for the tip!! Once it's open, you can just drag the image from the browser to the desktop to save (no right click needed).

Mr Rid
09-21-2010, 02:28 AM
Theres also some utility thing for Windows where you hold a key and L-click-drag to select an area and it immediately makes a jpeg on the desktop. I dont remember what its called.

prometheus
09-21-2010, 08:50 AM
isnt it called something like the screencut tool ..thatīs the direct translation thou for it in the start menu in windows 7.

And theres a program here too..
http://download.cnet.com/Screen-Cut/3000-2384_4-10715776.html

screen print works nicely too, when using print screen it automaticly saves and image on your selected folder, without having to paste in a paint program.

http://download.cnet.com/Screen-Print-amp-Capture-32/3000-2384_4-10135610.html?tag=mncol;pop

Michael

Mr Rid
09-22-2010, 01:47 AM
I think this ScreenHunter was the one I used before at a place I worked-
http://wisdom-soft.com/products/screenhunter_free.htm

erikals
09-28-2010, 01:37 PM
other alternatives,

video footage
vue, http://www.youtube.com/watch?v=mb6dJfelI-I
turbulence4D
ogo, http://www.youtube.com/watch?v=oW0ImR2zZ9M

it really depends on what look that is wanted> realistic, or fantasy/cartoon style

one can also of course blend techniques, for example using photos in the background and 3Dclouds in the foreground/ fly-through, if the shot makes it work.

prometheus
09-29-2010, 12:35 PM
Itīs gonna be interesting to see When a discussion shows up on where to go with Lightwave environment tools in the future.

Yeah erikals, vue clouds fly over are looking great and easy to setup, renders pretty decent I would say considering all the advanced light atmosphere behavior algoritms acounted for.

Maybe I should put together a concept visual scheme, showcasing what I believe would be great to have as environment,cloud tools and volumetrics, and maybe posting that in the Core forums, but I really feel trapped in a cage having to wait for core catch up with all other stuff before it will be useful.

Im just hoping they can start to pull something up but with core in mind and start presenting that for a lightwave 10 cycle.

Im no programmer and no tech guy, so it would only be a compilation of tecniques that is already in other software, but if one take a look at different solutions and how other software has approached it, you could nail down a concept plan based on goodies everywhere, itīs at least a start then Newtek has to listen, think hard and act ..sooner the better.
If no programmer would know how to, then put out som job advertisement for it please.

The best from vue spectral atmoshpere types volumetric lights, houdini cloud making with implicit surfaces and volumetric geometry or image 3d cloud generation with metaballs.

Anyone who knows something about the ogo taiki guy? or heard anything about If ogo taiki ever will be picked up again for further development?

Michael

erikals
09-29-2010, 02:34 PM
 
well, most backgrounds are not fly-through, so video can be used.
(i'll make a tutorial on it later on) the result is 360 animated realistic clouds.

adding a link to a test i made that is somewhat similar to this method,
http://www.youtube.com/watch?v=Q_O1dVGREWM

-------------------

realistic fly-through is the real challenge, and here the only good options you have is,...

A: video footage
B: vue
C: video footage combined with cg clouds for fly-through

-------------------

Ogo hasn't developed any new stuff in years, so i doubt it will see anything from that corner...

 

Red_Oddity
09-29-2010, 03:41 PM
I think this ScreenHunter was the one I used before at a place I worked-
http://wisdom-soft.com/products/screenhunter_free.htm

XnView supports various capture options as well, including the drag rectangle screen capture (among the bazillion file formats it supports and other tools it has)

prometheus
09-30-2010, 01:54 AM
 
well, most backgrounds are not fly-through, so video can be used.
(i'll make a tutorial on it later on) the result is 360 animated realistic clouds.

adding a link to a test i made that is somewhat similar to this method,
http://www.youtube.com/watch?v=Q_O1dVGREWM

-------------------

realistic fly-through is the real challenge, and here the only good options you have is,...

A: video footage
B: vue
C: video footage combined with cg clouds for fly-through

-------------------
Ogo hasn't developed any new stuff in years, so i doubt it will see anything from that corner...

 


Well thereīs really other options, and since vue is among out of lightwave stuff, I would say that Terragen would do that well too, except for itīs ridiculous slow, I just tested it on my new machine, but theré were very little improvement in speed for the previewer in Terragen and that is a killer for me in workflow restraining tweaking options.

And houdini is certainly capable of doing it too, but that requires some setup and extensive knowledge of houdini tools, so itīs no match for those who wantīs to dive in to vue for immidiate results.

You could also do it with hypervoxels, if you have a lot of time, the hard part is to mix in with a decent air atmosphere that matches the clouds.

I did some experiments yesterday, using a high density subdiv grid, with hypervoxels applied on the vertexes, a procedural on the dissolve channel and using world coordinates gives the base density shape, some y stretching and a procedural texture on that will give height variations, I bellieve it looks better than just adding it seperatly on point clusters.

If you Donīt need that realistic clouds, You could work with sprites perhaps, adding a gradient based on y distance to particle on lumunosity channel or distance to null ref helps adding volumetric feel to sprites, you
need to find a balance between subdivision grid settings and have big enough particle size, then drive the overall density look with a procedural on dissolve channel, this works nice to give a preview in open gl.

I would love to see a tool to allow extracting turbulence 4d fluid simulations to a static cloud shape.

If only Vue would implement a particle system or at least having tools to import particle sims and then have the option to add a voxel shader inside of vue,sort of a metacloud textures on to particles with metaball blending, that would really be something, doing smoke stuff is pretty limited
unless you go comping, I havenīt seen anyone doing a comp of
letīs say an aeroplane decending throu clouds with fire and smoke on the engines and having it obscured by the clouds while decending through it.

Otherwise I would go with ogo taiki.

Michael

erikals
09-30-2010, 04:56 AM
I havenīt seen anyone doing a comp of
letīs say an aeroplane decending throu clouds with fire and smoke on the engines and having it obscured by the clouds while decending through it.

hehe :]   now That's a challenge! :]

yet another idea is to model particles that has a cloudshape, for then to morph the shape. the problem here is that i don't know what method to use to make the particles render so they look like a cloud... i can apply HV to them, but they still won't look like cloud.

maybe this trick could be useful somehow.... (see the .zip attachment)
http://www.newtek.com/forums/showthread.php?t=112843

 

prometheus
09-30-2010, 07:29 AM
cloud sculpting techniques could be..

1.spraying points, erasing them, sculpting them (med (Edit.. oops swedish blooper ) With dragnet magnet tools.

2.Model geometry close to cloud shapes, have them in background layer, spray a high density cube field, and use the background geometry for cutting out particles in that shape, sort of filling geometry with points.
Use drill boolean and intersect.

3. use normal displacement on base shape in layout, save out transformed object and use as a cookie cutter as mentioned above.

4. create particle cluster with texture maps on birth rate, save out particles as transformed object,continue to transform to your liking in modeler.

The main reason I believe it might not look like clouds with hypervoxels, is probably due to that it need to react to air properties to start to feel like clouds, and also the fact that hypervoxels donīt metaball blend, another issue is that you would need an offset volume influence where a totaly different hypertexture can be applied for whispy smoothe edges of the clouds, and retaining billowing perlin fractals inside the voxel volume.

Even Vueīs metaclouds doesnīt have a good metaball blending, and the new harder spectral 2 meta materials are giving to sharp edges when tweaking, it needs that offset value also, to keep harder billows inside of metaclouds and smoother outsides.

Michael


Michael

erikals
09-30-2010, 07:39 AM
it might also be possible to use photosculpt to take a picture of the clouds to create 3D data.
http://www.photosculpt.net/gallery/textures-seamless-tileable/


another issue is that you would need an offset volume influence where a totaly different hypertexture can be applied for whispy smoothe edges of the clouds, and retaining billowing perlin fractals inside the voxel volume.

yes, have a couple of ideas on how to get around that, just need to make them work ;]
 

elektronikfreak
10-04-2010, 03:48 AM
Very interesting thread, undeed.

rrgraphic
12-09-2010, 10:47 AM
I would like to make a passage through the clouds, so I need to change the point of view of the clouds to see them from the top to the ground, is it possible? how can I do?

Iaian7
12-09-2010, 12:52 PM
Because of how the layered geometry trick works, it's not going to have quite the same depth, but it's certainly doable - just move your lights around so they're in front of (or above) the clouds instead of behind. The biggest problem is that you then have to deal with diffuse+shadow instead of translucency+shadow, and it's harder to get it looking decent. Texturing and lighting angle (you won't see any depth at all if the light is directly above, for example) will take some work. For anything but back-lit clouds, actual volumetric renders will usually be better looking. Just slow as heck, and Lightwave isn't the place to do it (I used to keep a copy of Bryce just for the volumetric engine).

prometheus
12-09-2010, 01:32 PM
You might be able to get a good look with creating a decent divided subpatch grid, and add hypervoxels sprites on the grid vertices to create a full density grid.

Start by control the amount of voxels (density) by increasing or decreasing the grid objects display subpatch levels in balance with particle size and use viper to look how your tweaks is looking,

add a procedural texture on hypervoxels dissolve channel set to world coordinates..scale that procedural texture aprox the same size as the grid.
Increase the hypertextures layer opacity to properly eat through the density grid for cloud holes.

Random voxel size helps add realism and a procedural on stretch channel gives random height of the clouds.
shading depth can be done with gradients on opacity and lumunosity channels.

Renders pretty fast within a couple of seconds and you have open gl feedback!..for final render match camera subpatch level to that of display subpatch level.
hereīs a quick setup within just a few minutes, I have better ones lying somewhere or can create much better thou:)


Michael
http://vimeo.com/user680656/videos

skywalker113
12-21-2010, 11:51 PM
I am researching the best way to make 3d clouds. One method I came up with is this.

I sprayed points in modeler. Then I applied sprites to them. The sprites are images of clouds cliped maped.

I am trying to make a sunset scene but The sprites dont seem to react to the direction of the sun. Just the intensity. Has anyone come acrossed this?

prometheus
12-22-2010, 12:27 AM
I am researching the best way to make 3d clouds. One method I came up with is this.

I sprayed points in modeler. Then I applied sprites to them. The sprites are images of clouds cliped maped.

I am trying to make a sunset scene but The sprites dont seem to react to the direction of the sun. Just the intensity. Has anyone come acrossed this?


sprites arenīt volumetric, so unless using real hypervoxels volume you have to fake the sunlight manually unfortunatly.

Michael

toby
12-22-2010, 12:40 AM
I don't think sprites ever shade, they're a constant color. Besides, if you're using photographs, the lighting is already baked in there. But if you want them to shade, just put them on polys instead -

prometheus
12-22-2010, 01:25 AM
You can fake shadows with gradients on y-distance to particle on lumunosity channel and opacity channels, and you can also use a distance to object gradient and use a null ref.


I think using a subidivided grid with procedural on the dissolve channel gives decent results, then Itīs a matter of putting gradients and getting som size variations in there, this technique is somewhat similar to maya cloud fields where fluid grid is used but with static textures.

some steps showcased with images..just basic setups in a couple of minutes, tweaking it with environment and lights would show it off better thou.


Michael

JohnMarchant
12-22-2010, 03:14 AM
Because of how the layered geometry trick works, it's not going to have quite the same depth, but it's certainly doable - just move your lights around so they're in front of (or above) the clouds instead of behind. The biggest problem is that you then have to deal with diffuse+shadow instead of translucency+shadow, and it's harder to get it looking decent. Texturing and lighting angle (you won't see any depth at all if the light is directly above, for example) will take some work. For anything but back-lit clouds, actual volumetric renders will usually be better looking. Just slow as heck, and Lightwave isn't the place to do it (I used to keep a copy of Bryce just for the volumetric engine).

Ive used Iaian7 method before after reading his tutorial and its definatly the best way ive seen to do it. Just watch the shadows if an object has to fly through it or anything, but its a good method.

I would imagine it would be possible to make a plugin to automate allot of the process.

Zimtower
12-25-2010, 05:05 AM
http://www.youtube.com/watch?v=wc-Ckt8aGTM&t=2m20s

If you are looking for cartoony clouds with super low render times, sprites attached to emitters works very well. I used the technique in this video.

Matelot13
03-16-2011, 11:30 AM
Thank you iaian, very useful setup.

However I'm having a hard time (well, I can't) making the clouds lighter, or change the change of the dark grey core of the clouds. What woud be the parameter to adjust?

Iaian7
03-16-2011, 04:56 PM
@Matelot13 Thanks! Glad you've found it useful. To adjust the colouration of the clouds, you'll probably want to adjust both the object surface nodes and the lighting in your scene.

The Mixer that feeds into the colour channel of the Translucency node helps shade the grey core of the clouds - you can change the grey colour to anything you want, including white, but keep in mind that it does help define a bit of the volume (you don't want it TOO light, or the final rendering may look a bit flat).

The lighting is fastest if you limit it to just a single Infinite light and a simple Ambient setting, but sometimes you'll get better results by using two lights at different angles (up to 30, maybe 45 degrees of separation between the two, depending on your scene). This helps spread the light diffusion through the cloud, resulting in larger areas of light.

You can also simply boost the ambient and main light intensity - the tutorial uses values set at 50% to give balanced results (no burning of highlights, etc.). You can certainly go higher than that, however, if your clouds are too dark.

Hope that helps!

Matelot13
03-17-2011, 12:46 AM
Thank you John
Adjusting the ambient color and intensity gave me the results I wanted. :thumbsup:

Iaian7
03-18-2011, 12:12 AM
Fantastic! Glad it's working. :D

prometheus
03-22-2011, 02:13 PM
since itīs cloud related...Im doing some test with ozone, might be of interest..in the lightwave community threads Ivé posted my impressions and some of my findings.

hereīs a simple rough hypervoxel trail test trough clouds with ozone 5 and lightwave 10

Just tested how it would be obscured by clouds, didnīt bother about getting a good voxel trail thou:D

http://vimeo.com/21359403

Michael