Volumetric Shadows from Texture

[gabio]

Source (http://www.stormpages.com/eeshlo/otherBlender.html)
http://www.stormpages.com/eeshlo/otherBlender_files/vLight.jpg This is an example of how to create light that is affected by what it passes through, as is done here with a stained glass window. There might be other or better ways to do this like halos (this is a very early file from when I started with Blender). This file is not documented but it still should be reasonably obvious as to how I did this. Its all fake naturally!
blend file(zip) (http://www.stormpages.com/eeshlo/otherBlender_files/vLight.zip)

[Apollux]

Really interesting use of dupliframes.

If I recall correctly that is almost the same technique that was used to fake volumetric smoke in the game engine, but now implemented in a lot more elegant fashion.

[December]

Its all fake naturally!

And there in lies my problem. Imagine a concert lighting rig, with 24 intelligent lights (with patterns, mostly just black and white patterns, but the lights have built in CMY colour changers) and 48 par cans (just coloured beams of light), The ones with patterns need to move around (I would normally do a short animation) and change colour. This would be near impossible using the example provided (Although it does look really cool).

Does anyone know if any of the external renders would provide the ability to do what 3D Studio Max does as far as volumetrics goes? This is just about the only thing that is holding me back from totally switching to Blender.. I love everything else about it. Unfortunatly just about every render I do needs this type of lighting!

[Apollux]

Honestly, I don't see the dificulty of doing what you say based on the example provided.

If you didn't look carefully, the example isn't faking the ligh but the smoke itself. Light can have any color or any animation and it will still work.. and the better is that the skmoke can be animated as well on the IPO curve window.

However, if Blender isn t the tool for you, then it isn't the tool for you.

[December]

If you didn't look carefully, the example isn't faking the ligh but the smoke itself. Light can have any color or any animation and it will still work.. and the better is that the skmoke can be animated as well on the IPO curve window.

Maybe I should take a more carefull look at that example then :)

However, if Blender isn t the tool for you, then it isn't the tool for you.

Ah, but I like Blender a lot.. I am simply trying to figure out a few things I am used to from other programs. Modeling in Blender is generally sooo easy!

[members only hunter]

a little explanation would be nice without having to download the blend file.

i have no use for it now but would love to find out how you would do this.

chris

[Apollux]

I'm preparing a more extensive example.. one question: Do you need it to be 100% real or can it be visually enhanced?

I was thinking of adding a glow and blur FX on top, but that will be cheating reallity (unless your intended audience is way behond the legal alcohool/blood level, because in that case it would still be real :twisted: )

Reallity is what your mind perceives.

[Apollux]

Here it is at last, sorry for the wait but university got my hands full.

The Volumetric Fog is on layers 3 and 4.

It is just a set of dupliframed planes with a custom made SMOKE material. The material is what does the real trick.

Keep and eye on this settings:

Color: Black
Alpha: 0.000
Reflection: 0.000
Emit: 0.000
Ambient: 0.000
Translucency: 0.000
Ztransperency: ON
Shadows: ON
Traceable: OFF
Radiosity: OFF

Specularity: 1.705
Spec Transp.: 0.075
Hardness: 8.000

Those last 3 settings are the most important ones.

By doing small (and I really mean small) changes those settings you can control the look and feel of the volumetric smoke. Feel free to experiment on your own.


Apollux.

BTW, to get shadows you will need to turn raytracing on, Zbuffered shadows inside the smoke are not possible.

The pict with volumetric smoke, rendered at 640 x 480 and OSA of 5 took 1/2 and hour to render :eek: But it can be streamlined if instead of filling the whole concert hall with smoke, a focalized smoke curtain like the one in the previous example was used.

And yes, you can animate the lights any way you like.

Damm!! The zip file has 371 Kbs, so CGTalk won't allow me to upload it. Anyone willing to host it?

[iluvgfx]

Hi Apollux.

I will host it on my website.mail me the file at satishgodaNUKETHIS@gmail.com (remove NUKETHIS)

[Apollux]

Hi Apollux.

I will host it on my website.mail me the file at satishgodaNUKETHIS@gmail.com (remove NUKETHIS)

Thanks bro, just sent the .blend file.

The blend is about 470 kb (mostly due to the packaged textures). I guess it is better that you decide the compression option (if any) to distribute it, because you know better what fits your server.

[iluvgfx]

No problem Apollux.

here is your file, zipped and ready to download.
http://satishgoda.com/blender/apollux/concert.zip

i also send you an e-mail with the link. (and a gmail invitation too http://cgtalk.com/images/smilies/thumbsup.gif)

[Apollux]

iluvgfx: :thumbsup:

Let's hope the blend is usefull for somebody.

[December]

Wow, thanks for the tutorial.. it gets the effect I need :) I'll have a play with the values you mentioned and see how I go for my next big show. Thanks both you guys for writting and hosting the file.. your efforts are much appreciated.

PS: Sorry for the long delay in getting back to check this thread, been busy doing shows.. sadly I don't get the time to do renderings of all the shows we do.. for many just do an AudoCAD lighting design :-(

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