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stevenpalomino
07-04-2010, 01:52 AM
I'm having the hardest time trying to figure out Ambient occlusion in LW. It seems like it's much easier in other packages, but in LW you have to add it as a node? I think I might be doing something wrong then because it just turns my materials into grainy objects. Is there a tutorial out there that can clarify the process? I've watched William Vaughan's tutorial on it.. but I've already got a material set on my object. Do I need to make a separate pass or something? Thanks in advance!
Steven

PS you can see in the attachment I've added the node only to the pants

Kuzey
07-04-2010, 04:23 AM
edit...I see you saw the video. I would play around with the setting and see what you get. Object scale might be a factor in how it works too..

Kuzey

stevenpalomino
07-04-2010, 04:48 AM
finally figured it out. I was using the "infinite" option instead of the ranged option in the occlusion 1 node. here's some before and after (with & without amb occ) pictures. Sure it needs some tweaking.. but worked after all :) next question:

How in the world do I get soft shadows with area lights??

Iain
07-04-2010, 04:56 AM
How in the world do I get soft shadows with area lights??

Scale the light up. Bigger the light, softer the shadow.

Kuzey
07-04-2010, 04:57 AM
You can get nice soft shadows with Dome lights...there's a video on that one too :)

Kuzey

stevenpalomino
07-04-2010, 05:03 AM
oops forgot about that :P thanks :D

Tzan
07-04-2010, 11:14 AM
Just thought I would post this.
100% SG_AmbOcc_Exp no lights.

stevenpalomino
07-04-2010, 03:34 PM
Howd you do that?? Photoshop?

Tzan
07-05-2010, 12:27 PM
How did I do what?

Modeled in LW
Applied SG_AmbOcc_Exp.p shader, You can get that from Flay. there is also a node version.
The ambient was set to 100%, no lights
color 201...
diffuse 90

Thats rendered straight out of Layout, no photoshop

stevenpalomino
07-05-2010, 02:44 PM
hmm.. I installed the plugin.. but where is it under :S

Iain
07-05-2010, 02:59 PM
Add it to your material in the Shaders Tab of the Material Editor.

Default settings are pretty good-just change the Max Ray Length (basically the extent of the effect) to suit the scale of the object.

stevenpalomino
07-05-2010, 03:22 PM
ahhh okay I see.. would it plug into the main diffuse of each material? seems like it's a bit of a hassle to plug it into each material. I guess it'd be easier to just assign it to everything and set it up as a pass correct?

Speaking of passes. How do I set up an occlusion pass? I'm coming from XSI so it's just "Create occlusion pass" there and then it renders and comps automatically.. How do I do this in LW?

Bog
07-05-2010, 09:42 PM
Ha ha ha... "create occlusion pass" indeed. No, we work for a living around here :P

You have to save a copy of your objects out with the Ambient Occlusion shader node applied (or as stated the SG_AmbOcc shader or node) to all your objects' surfaces. Then set your scene up with 100% ambient light, no other lights, saving out to a different folder.

Then take a drink ;)

It's a heckofalot easier with ShaderMeister (which is on my to-buy list, below beer but above new socks) but that's a commercial tool.

Breakouts in LW are, by default, A Bit of a Pain. If anyone's got a better way of breaking out an AO pass, I'm all ears. Eyes. Monitors. Whatever.

I should say, though, that's specifically AO. For all your other buffers (Spec, reflec, yada yada) you want to pop open your Image Processing panel, and locate the Add Image Filter dropdown in the Processing Tab.

Adding the Render Buffer Export plugin will let you set buffer savers for each channel. Yes, you need a separate instance of the plugin for each channel. Yes, you can have another drink now.

EXRTrader from those same fine and fantastic folks at DB&W, who also do ShaderMeister, will let you handle all your buffer savers flexibly in a single plugin, just like grown-ups do.

stevenpalomino
07-05-2010, 09:47 PM
Yeah.. i was trying to find a less painful way of doing ambient occlusion.. but I guess i'll have to buy the plugin.. although.. the amb occ + Exrtrader deal doesn't look too bad.. $100 for something that'll save me hours at rendertime? Yes please!

Bog
07-05-2010, 09:53 PM
The folks who built those tools are Top Notch as well, which is always good. I like doing business with good people.

stevenpalomino
07-05-2010, 10:32 PM
Yeah.. I'm not sure I would buy the "I slapped this together last night" ones.. at least it sounds like a bad idea ;)

Bog
07-05-2010, 10:42 PM
Don't tell me you've ever fibbed and said that a five-day project took you three days, just to make yourself look good. XSI can't be *THAT* different...! ;)

stevenpalomino
07-05-2010, 10:45 PM
haha can't say I've done that.. I have, however, told someone I was going to take a week knowing it would only take a few days so that I could finish "early" and appear hard-working ;) haha

archijam
07-05-2010, 11:47 PM
It's very nice. Who knows, maybe they'll do a Siggraph deal, since I know they are there this year (visiting).

There is also a thread active at the moment about separating shadow pass from diffuse. Have a look (cageman perhaps?).

Captain Obvious
07-06-2010, 02:23 AM
shaderMeister is the single best plugin ever developed for any app, ever. I can't believe I went for years without it!

archijam
07-06-2010, 04:51 AM
Damn .. edit limit.

Here's that link:

http://www.newtek.com/forums/showpost.php?p=1034283&postcount=67

jrandom
07-06-2010, 10:43 AM
I've always done occlusion renders by setting my light source to 0% light, 100% ambient, and used GI w/ Ambient Occlusion checked.

I'm assuming this is a lot slower than using an AO shader?

Lightwolf
07-06-2010, 10:50 AM
I'm assuming this is a lot slower than using an AO shader?
Not necessarily - but it's still not a "pure" pass, since it retains the surface colours and other properties.

Cheers,
Mike

Andyjaggy
07-06-2010, 11:27 AM
This is one of the long standing problems with Lightwave, setting up multiple passes and shading is a pain. Uck. I certainly don't miss the days of having to save 10 copies of an object and scene just to get the renders I needed.

Luckily there are some plugins that help, but I had to laugh when I read this on the db&w page.

"Unfortunately due to the nature of the LightWave 3D shading systems, things aren't as simple as they seem to be. Since shaderMeister is applied as a shader, it has limited access to some of the nodal shading information and can also only override some of the nodal data."

That's how it goes in Lightwave land I guess.

archijam
07-06-2010, 11:52 AM
I wondered why you dropped in on us from modo land ;) ..

Lightwolf
07-06-2010, 12:15 PM
That's how it goes in Lightwave land I guess.
Well, on the other hand: It has a nodal shading system... :D

Cheers,
Mike

stevenpalomino
07-06-2010, 12:46 PM
Another question: What are frame buffers and how are they used?

VirtualFM
07-06-2010, 04:15 PM
Ha ha ha... "create occlusion pass" indeed. No, we work for a living around here :P

You have to save a copy of your objects out with the Ambient Occlusion shader node applied (or as stated the SG_AmbOcc shader or node) to all your objects' surfaces. Then set your scene up with 100% ambient light, no other lights, saving out to a different folder.

Then take a drink ;)


Hum... You all should take a look at DP_Filter

http://pagesperso-orange.fr/dpont/plugins/nodes/DP_Filter.html

Examples by Gerardo:
http://forums.cgsociety.org/showthread.php?f=5&t=781804

zarti
07-06-2010, 04:53 PM
shaderMeister is the single best plugin ever developed for any app, ever. I can't believe I went for years without it!

i would agree 100 % if you would put the word " LightWave " somewhere in your post .

Mike is lucky because LW is what it is and we are lucky because Mike is lucky . :hey:

so a good % of agreement goes exclusively to its usefulness , or better its necessity !

:goodluck:





.cheers

Captain Obvious
07-06-2010, 09:24 PM
i would agree 100 % if you would put the word " LightWave " somewhere in your post .
My measurement for how good a plugin is the delta between how good the app is with and without it.

ingo
07-07-2010, 01:35 AM
My measurement for how good a plugin is the delta between how good the app is with and without it.

Is there a plugin for that, maybe a delta node ? :p