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realgray
03-12-2011, 08:17 PM
Hi all, are there any moderate to advanced nodal texture training around. I would like to expand my nodal abilities but finding tutorials scarce.
Thanks.

nickdigital
03-12-2011, 09:33 PM
If you can find an old copy of James Willmott's node training material that would be the way to go.

Anti-Distinctly
03-13-2011, 06:53 AM
I was thinking about doing some training videos for nodes...what kind of things are you trying to achieve realgray?

realgray
03-13-2011, 06:44 PM
Basically all the math ones. Nodes are very different to the photoshop like system and I'm finding resources sparse. I'm mainly looking for a breakdown on what each node does with examples. I guess it may not exist.

jameswillmott
03-13-2011, 07:16 PM
Asking for a breakdown on how nodes work is sort-of like asking what each keyword in a programming language does, by themselves they aren't that useful, it's only together that they have any real sort of power.

You don't need an explanation of Add/Subtract etc I hope, so I'll cover the others.

Boxstep: Any value less than Begin gets clamped to 0, any value between Begin and End gets remapped linearly to 0 -> 1.0. Any value greater than End gets clamped to 1.

Ceil: Ceiling function, returns next largest integer from the input. ie 1.3 -> 2.0 , 5.9->6.0

Fresnel: Physically correct Fresnel reflectance based on incidence angle and refractive index.

Invert: Subtracts the input from 1.0 , so a range 0->1 becomes 1->0.

Logic: Tests input A against input B. Passes through input True, if the condition is true and input False, if the condition is false.

Max: Returns the larger of the two inputs.

Min: Returns the smaller of the two inputs.

Mod: Returns the modulus ( remainder after division ) of input A over input B.

Pow: Exponent function, Pow of 2 would be the equivalent of A squared, for example.

Sign: I think it negates the input, -1 becomes 1 etc.

SmoothStep: Like BoxStep but the remapping between Begin and End is smoothed out so there isn't an abrupt change.


Did you need the vector ones as well?

realgray
03-13-2011, 08:54 PM
Thank you James for the help.

cgisoul
03-14-2011, 12:58 AM
Basically all the math ones. Nodes are very different to the photoshop like system and I'm finding resources sparse. I'm mainly looking for a breakdown on what each node does with examples. I guess it may not exist.

http://www.kurvstudios.com/lightwave/texturing.php

A list of tutorials from Kurvstudio about nodes and LightWave surfacing.

Hope this helps.

jameswillmott
03-14-2011, 01:10 AM
http://www.kurvstudios.com/lightwave/texturing.php

A list of tutorials from Kurvstudio about nodes and LightWave surfacing.


Unfortunately, none of those videos are legally Kurv's to sell. Both Adam and myself have formally withdrawn Kurv's right to sell those titles, so please do not purchase them. Neither of us will see any royalties from the sale but regardless, Kurv isn't licensed to sell them anyway.

cgisoul
03-14-2011, 01:27 AM
Sorry about that James, I wasn't aware of it.

Wondering why they are still selling them through their site then.

Anti-Distinctly
03-14-2011, 03:25 AM
@realgray - one method I tend to use when it comes to the math nodes is to plug the result of a calculation into the diffuse input of a surface (not the colour) then you can use your mouse in the image preview to see the result of the calculation as the rgb will be the result of the calc. Here's a picture of a texture I knocked up and in the image viewer I have the mouse over part of the texture at (244,198) which shows my nodes network has a result of 0.2491.

http://www.newtek.com/forums/attachment.php?attachmentid=93637&stc=1&d=1300094710


Unfortunately, none of those videos are legally Kurv's to sell.
Is it not possible to get an injunction to prevent him from selling them?

Hominid 3D
03-14-2011, 04:10 AM
What is it with Kurv getting such a bad rep lately? Weren´t they THE authority on tutorials for LW for many years?

OnlineRender
03-14-2011, 04:19 AM
What is it with Kurv getting such a bad rep lately? Weren´t they THE authority on tutorials for LW for many years?

lets not go there ! please .

Hominid 3D
03-14-2011, 04:23 AM
uups, sorry. That sensitive a subject? I had no idea, just noticed a lot of negative energy around that and was wondering. Me shut up now..

jameswillmott
03-14-2011, 05:36 AM
Sorry about that James, I wasn't aware of it.

Wondering why they are still selling them through their site then.

That's ok, sorry if I came across a bit harsh. No idea why they're still selling them. But thanks for letting us know!

Portnoy
03-14-2011, 08:04 AM
To get back on subject though, some good training videos or tutorials on Nodes would be very useful. Nodes has always been a hard concept for me, I understand the layer system much better but do realize the power of nodes.

Don

cgisoul
03-14-2011, 08:35 AM
That's ok, sorry if I came across a bit harsh. No idea why they're still selling them. But thanks for letting us know!

No, it's all good m8. Actually I saw them there long time ago. Glad that somehow I helped.


uups, sorry. That sensitive a subject? I had no idea, just noticed a lot of negative energy around that and was wondering. Me shut up now..

Apparently that has to do with how Kurv does/runs the business. Though they are "mainly" the only few places with good Lightwave tutorials, the Authors of the tutorials don't get much out of the business/income. Not sure, there a lot of stories about Kurvstudio in this regard. James is one of few I know have quit doing tuts for Kurv.

omichon
03-14-2011, 09:37 AM
Did you need the vector ones as well?

Yes, please :)
I am still a bit confused with some of them.

OnlineRender
03-14-2011, 09:44 AM
Ohh come on ...nodes nodes nodes

Matelot13
03-17-2011, 09:25 AM
I'd love a tutorial also, but to me knowing how they "work" is pointless unless its applied to real examples.
For instance, how to use SS2 and with which modifiers, same with dialectrics, blurry refractions, skin, corrosion...

jameswillmott
03-23-2011, 05:10 PM
Add: Adds the nth element of one vector to the nth element in another. A vector [1,2,3] added to [4,5,6] is [5,7,9]. The neat thing with this is a Color can be considered a Vector, so you can use this node to add two Color's together.

Add4: As above, but you can add up to four vectors at once.

Add Scaled: Like Add, but scales the B input before adding.
Input A: [1,2,3]
Input B: [4,6,8]
Scale : 0.5 ( B scaled is [2,3,4] )

Result: Input A + B scaled = [3,5,7]

Cross: Vector cross product, usually used to derive a vector that is perpendicular to two others. You could use this to construct a polygon normal, for example, by creating two vectors based on adjacent edges.

http://en.wikipedia.org/wiki/Cross_product

Distance: Distance from Input A to Input B.

Divide: Like Add, the nth element of Input A is divided by the nth element of Input B

Dot: Vector dot product. With normalised vectors, the result is the cosine of the angle between them. With unnormalised vectors the result can be used to find the projection of one vector perpendicularly to another.

http://en.wikipedia.org/wiki/Dot_product

Length: The magnitude of the vector.

Multiply: Like Add and Divide. nth element times the nth element.

Normalise: Adjusts the length of the vector to 1, maintains it's direction.

Scale: Scales all the elements of the vector.

Subtract: Like Add, Divide, Multiply etc.

Subtract Scaled: Like Add Scaled.

Transform: Can transform the input vector from world space to object space and from object space to world space.

Transform2: Can transform a vector based on an arbitrary coordinate system which you define by setting the values of the Up, Right, and Forward inputs.


I'd love a tutorial also, but to me knowing how they "work" is pointless unless its applied to real examples.
For instance, how to use SS2 and with which modifiers, same with dialectrics, blurry refractions, skin, corrosion...

Tricky, since there is no limit to what you can do with them and you might get the result you want using a node in a completely strange and inappropriate. Using base nodes should be easy enough to demonstrate though.

omichon
03-24-2011, 06:45 AM
Thanks for this, James ! I have a better idea of what could be done with Cross and Dot Product now (well, I hope so ;) ).

lardbros
08-04-2011, 06:26 AM
All great knowledge and all that, but some people (ie me) need real-life examples of how it can be used... and how to build a energy-conserving material using nodes, and make sure your diffuse etc is working correctly. This is what I find so hard with nodes... some things I expect to work, don't, so I give up.

Are Newtek going to release some advanced nodes training? Or even basic stuff?

Like, for example... how to make a brushed stainless steel shader using material nodes, and then show us how to do the same but with standard nodes. The benefits of either... and how to add rust, scrapes etc.

I am definitely one of those that learns by example, it's tough to know what all these math functions are doing to values if you're an artist, not a programmy type! :(

UnCommonGrafx
08-04-2011, 07:17 AM
While time is precious, I think there are a few things we can do now to learn more about nodes, in real-world situations.

Since nodes arrived, and more so since Denis starting coding his nodes, I have advocated for looking at other 3D apps training about nodes. In this way, we can see so many things: what we have, a new language, what it is we have or not.

For example, the biggest gripe I now have about LW's node system is that it is not; that is to say, it's not a system as much as a bunch of systems, not connected. Proof of concept of being able to build one system has been demonstrated so it is hoped to be available to us(ers) soon. (*Dreamer statement warning*)

Right now, we get to learn a few systems, that attempt to interact in function but not communication. Here's to seeing the POC in the pudding.


Oh, and the other thing to do is to practice with them. Math nodes and colors are really cool. Tied into motion, really amazing things can be achieved.

Play and practice for practice is play.