Very Nasty Very Bad bad BAD!! shadow. Not all corners r supposed to get AO

is there any render speed difference with any of these settings? Since they all look "good", whichever one renders the fastest might be the choice one. (not sure how much math increases renderspeed)

nice work Ajax can you make it smaller more subtle?

GWeb, actually if you take a look at the mathematical procedure behind AO, yes all corners are supposed to get it. That's how the AO algorithm works and it's also one of the reason AO is far from a perfect solution for true radiant lighting. Gareee, Not much difference in speed between the four shaders shown, no. It's just a matter of which noise pattern you like the best. Stonemason, Yep, you can make it smaller and more subtle. The size of the individual dirt grains is controlled with the scale parameters of whichever noise node you use. The density is controlled with the bias parameter on the same node. Controlling how far the dirt extends from the corners is a matter of filtering the AO output through some math nodes.

Attached Link: http://www-viz.tamu.edu/students/bmoyer/617/ambocc/

get that bump out of the gradient slot!!..lol :) it's a nice effect with the shader,it looks a bit grainy,& obviously made up of dots..is there any way to clean that up?

Attached Link: http://www.metafex.net/cinefex/tutorials/dn/

By the title of this thread I thought I was going to have to suggest that you turn on the nudity flag. LOL

I'm not sure what I'm looking for,just less apparent dots I guess,can you control the amount of dots?..make it alot more dense but keep the opacity http://www.maxon.net/pages/products/c4d/r85/images/dirt_nodirt.jpg

I thought he'd been running around the back yard naked again ;P

Stonemason Excellent link!! you have made my point acrossed!! Thanks!!!!!

Looks doable. Just a matter of spending lots of time tweaking I think. Let me see what I can do.

My suggestion is to have AO shading interact with property shading for color balancing. I wish I downloaded P6 stead of Box but I want a copy of book and a pretty box hehe.

Top right is better but not satistified. After looking at all of these. AO is not supposed to look dusty. AO is supposed to slight decrease or increase color temperature along with shading.

Can you match AO color with the sphere's color shading? I also would like you to make another sample like this but with lighter color in AO setting. GWeb

GWeb, I realise the title of this thread, containing the rather subtle words "dirt shaders", might not have given it away to you, but the whole point of what I'm doing here is to use AO as a means of filling corners with dirt. I had hoped that the very first sentence in this thread ("...it's possible to create shaders that automatically fill nooks and crannies with dirt") might have hinted that, but apparently I was being too obscure. "AO is not supposed to look dusty" Surprisingly enough, DIRT IS SUPPOSED TO LOOK DUSTY! Perhaps I'm still being too subtle, so I'll quote your own words from post 6 back at you: "Very Nasty Very Bad bad BAD!!" If you aren't interested in shaders that look dirty and/or dusty, please do us both a favour and go and find a thread that isn't about dirt shaders.

Hehe, now the entire of Poserdom can use the old Ambient occlusion for "dirty shaders" trick Renderman users have had for some time. Good to see we're spreading the love grin I personally like the top left, the top-right is nice for say a "tarnished" look, but the top-left really does the "dirt thing" for me,

Ajax, This is outstanding. I agree with Eternl Knight on the dirt effect preferences. I have a couple of questions:- a) Would this work for bump and displacement mapped detail? b) Although not strictly 'dirt', but coming under the heading of 'weathering' would it be possible to use the settings on the ball at top left with a rusty colour, and the settings on the ball at top right as is, at the same time, to create a rusting dirty ball? Cheers Ian

Yeah, it's something I've wanted to see in the material room for a long time :-) I like the top left too, but I think I like the bottom right just a little better. I actually only put the top right one in as a control. There's almost no dirt in it at all.

Ian, Yep, sure will work for bump and displacement :-) Basically it drives a blender, so you just blend your dirt bump against your clean surface bump. Layering dirt AND rust will make the shader more complex with a bunch more nodes so it will be more difficult to manipulate in the material room and will render slower, but it's certainly doable. In the longer term I'd like to put together some more complex shaders like that. I'm really just playing with my new toy at the moment.

The head looks great in pewter. Thanks for answering my questions. Can't play until my Wait-Club membership expires .... Ian

Ajax..the top 2 are spot on! Cheers Stefan

I have visions of naked Jessis in very very dirty temples... :D

Ajax, this is outstanding! thanks for sharing!! ----- stewer! lol :P

can you screen cap the top right settings? That looks like it would be good for victorian ship and vehicle renders. (it'd probably look nice on the martian tripod from Daz, or the Nautilus from Daz as well...)

the top right settings are great! I agree with you Gareee and wish Ajax can share with us the setting too ;)

Ajax - Absolutely bloody brilliant!! I love them ALL - please please please release a "Dirt Pack"!!! Wow!!

Hmm I just had a thought... if you applied negative math nodes, couldn't this be converted to some kinda of highlight lighter spots type of shader setting?

Can this be used to make a brisk texture look dirty? (Each individual brick, as opposed to only the corners of the mesh) Also please post a screen cap of the settings you used for the balls. Excellent use of the node by the way. Creative use like this could eliminate the use of textures for much of the structures within a scene.

Something that would be really cool in poser, would be adding the ability to "bake" these on textures, and then save those textures. It's using in lightwave all the time to create actual texture maps. Since the P6 material room is really blossoming, that would be a way to "share" the new tech with the older poser version users. Not that I think it'll happen...

Gareee, I agree fully on the Victorian vehicles, a particular interest of mine. Bring on the rivets, coach-bolts and leaf springs! Ian

Hmmm I'm also wondering, if this was included in a toon render, if it could be used to create a "stipple" drawing effect? Animated, that might be killer!

Ajax, s always, the master of material nodes! This is a great piece of work, thanks fo rsharing! I cannot wait until I have to stop waiting }-) Shogakusha

Ah, another thought.. maybe this could be combined with the slime shader as well? I want my P6... >whine

Garee: "Hmm I just had a thought... if you applied negative math nodes, couldn't this be converted to some kinda of highlight lighter spots type of shader setting?" Perhaps to simulate the shiny spots on larger bronze statues, where they've been rubbed by the hands of thousands of visiting tourists...?

Ajax, Yeah I wasnt interested in dirt shader. I was interested in just the AO shading that interacts the lights. Your method for dirt shader is indeed good ones. GWeb

Umm after looking at images and I reviewed AO function. The AO is supposed to be sensitive to the light that may affect the dirt shading. Just thought you might like to know.

God bless your dirty balls sir!