Complex UV Layout in Maya
Over the last couple of years UV layout in Maya has changed for the better. In this course we're going to be taking a look at some of those changes as we UV map an entire character
# 1 21-01-2011 , 04:23 PM
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light-hearted question regarding 'nodes'...

this is just just a general question which is open to a lot of personal interpretation in the answer (i would imagine)

-- what is, or rather, how should I interpret, a node?

when i see the word 'node' i envisage a large-ish rubber.. nipple(or collection of)... -- something that resembles a cross between a dog toy and sex 'aid'

so when tutorials say 'assign a shader node' or similar, I'm not quite getting the feel of things.

if i google the question i just get 'maya uses a node based structure' which doesn't really clarify things.

how do other users regard 'nodes'...??

# 2 21-01-2011 , 05:12 PM
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why dont you imagine a big container and you are putting all your toy nipples in the container. user added image

you could open the hypergraph connections and have a look at things visually.

# 3 21-01-2011 , 05:16 PM
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Interesting question. But I never imagined a nipple when the idea of a node comes to mind lol. I see nodes like leaves on a tree. A leaf is a leaf and has its own attributes, however when connected to a branch that's connected to other leaves and branches, it not just a leaf but an important part of what enables something greater to function.


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# 4 21-01-2011 , 05:28 PM
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Maya is essentially a network of nodes, each with their own attributes, all connected to each other.
Yeah, I know, that's not really helpful.
So how I think of that, is a node is a virtual box that contains a bunch of information. The type of information determines exactly what type of node it is, and the exact values of the information determine exactly how that node behaves (or looks).

So a shader node will have types of information relating to color, how shiny, how reflective etc.
Polygon geometry generally consists of two types of nodes connected together, a shape node and a transform node. The shape node will tell maya (and you) what that geo looks like, is it square, round, how smooth is it. The transform node will say where that geo is and how it is oriented, pretty much the translate, scale, and rotate information (along with some other stuff).

So how do you see all this information? The attribute editor of course. All the different tabs for any object are all the nodes that are connected together. A shape node, a transform node, a material (e.g. lambert1), maybe some other nodes too. How do you see how these nodes are all connected? The hypergraph. Open it up and choose graph selected. You'll see how these nodes are connected, because the connections are directional, and they also connect via the attributes themselves. But I think that's enough for now. I hope that helps you out. I think it's important to understand how maya really works at the base level in order to do lots of troubleshooting and finding faster workflows.

# 5 21-01-2011 , 10:10 PM
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LOL you either watch a lot of XXX or need to get out more......

I agree with Genny, I had a bit of trouble understanding what it represents but a tree is the closest thing I could imagine.

Function wise stwert is right.....I think Star Trek when I hear the word node, a connection point for data transfer...and as stwert said each node has its particular data that are put together to create the tree and of course the object.

I assume the attribute editor, hypergraph and the outliner all have similar functions which let you see the actual tree structure where the connections of the nodes are visible. As far as I see (stwert?) the attribute editor is a basic view with each tab representing the node and properties, the outliner is similar which when selected will work in tandem with the AE. The Hypergraph (only seen it once) is the same but gives you a much better visualisation of the connections you have on screen (stwert?). I dont know which one is best but I use the outliner mostly now and select the object or group to get the info of the properties of each node in the attribute editor.

Cheers bullet


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# 6 21-01-2011 , 10:18 PM
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Well... yes and no I would say. Yes, they all show nodes and to some extent connections, but I think they get used in very different ways. The outliner only shows nodes, not attributes, whereas the AE shows mainly attributes, and only a few nodes. The hypergraph is somewhere in between, because you can see (pretty much like in the hypershade) how the nodes are connected via attributes. E.g. in the hypershade, you can plug a file texture into a certain attribute. Now you can do that in the AE, but you only see one node at a time, and you can't really see that at all in the outliner. The outliner is good for selection and hierarchical stuff (grouping and parenting), but that can all be done in the hypergraph too.

Outliner: An "outline" of all the nodes in the scene and how they are connected at a very general level
Attribute Editor: All the attributes for a given node, and a few other nodes (in tabs) that are connected to it
Hypershade/hypergraph: A visual depiction of the connections between nodes and the attributes by which they are connected


Last edited by stwert; 21-01-2011 at 10:22 PM.
# 7 21-01-2011 , 10:24 PM
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I think it's important to understand how maya really works at the base level in order to do lots of troubleshooting and finding faster workflows.


I agree, this is very true, and the real reason behind the question.

for example, if i'm renaming an object (although I normally use the outliner) - what node would I choose in the AE? I would assume it's the shape nipple, but it seems it's the transform... unless I'm looking at things wrong...

also, the history is somehow connected to these 'nodes' insomuch as they appear in the AE too...?

# 8 21-01-2011 , 10:30 PM
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LOL stwert, thanks mate. So they basically have a little bit of each but dont have the whole car so to speak? Yes I see what you mean...I use the outliner quite a bit now (never used to) to select the geo/groups etc for ease of modelling...hiding/transforming/texture/smooth etc and use that in conjunction the with AE for the properties I wish to edit. I havent really tried the hypergraph?? I use the hypershade a lot when I UV though.

Is there any reason why they dont have a graphical editor with all of the functions?

cheers bullet


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# 9 22-01-2011 , 07:05 AM
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@se7enhedd: If you name some geo in the AE, you'll notice that if you rename the transform node, it will rename the shapeNode for you, kinda useful. In the outliner, the transform node is the upper level node, so it can be renamed there as well. If you rename the shape node, it won't update the transform node name, I think because of the directional connection. Hope that makes some sense, it might just be arbitrary, I don't know.
@bullet: I don't really use the hypergraph much yet either, but it's something I'd like to focus on more. I think they don't have a one-for-all cause it would be super overwhelming and not really as useful.

# 10 22-01-2011 , 09:24 AM
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Yeh stwert I guees you are right...I too would like to utilise it more but I will have to get used to the outliner first...then the hypergraph.

cheers bullet


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# 11 22-01-2011 , 01:44 PM
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right - so... 'pCylinder1' is the actual 'thing'; 'pCylinderShape1' is how the 'thing' is shaped, sized etc...

now, if I change the name to 'tube' - I get 'tube' & 'tubeShape', but there's still 'polyCylinder' under inputs..?

also what confuses things (or me at least) is there doesn't appear to be much logic in naming conventions - there's pCylinder1, then pCylinderShape1 (shouldn't that be pCylinder1Shape) and then as mentioned above - polyCylinder1 - (why poly and not p) ?

# 12 22-01-2011 , 02:14 PM
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Now you are confusing me! LOL...ok it should re-name 'polycylinder' but it doesnt...you can just rename that too mate in the AE. As for the naming convention etc I dont know but it will have something to do with programming...ie MEL scripting...my Survey software is similar and its how the langauge works is all I would expect.

Cheers bullet


bullet1968

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# 13 22-01-2011 , 03:19 PM
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right - so... 'pCylinder1' is the actual 'thing'; 'pCylinderShape1' is how the 'thing' is shaped, sized etc... ?


The "size" would be under the transform node, since that handles scale, translation, rotation and the like.


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# 14 22-01-2011 , 05:37 PM
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Ah, you found the creation node... haha, yes quite confusing. In addition to the shape and transform nodes of an object, there is a node that contains all the info on how it was created. That is your "polyCylinder". In your channel box you can use this node to change divisions, radius, etc. If you delete history, or have construction history turned off, that node will not appear, or it will be disconnected. For most things you can safely ignore the name of this node.

pCylinder1Shape: No, because the number always comes last. I think that's so maya can auto rename easier. If you duplicate, you will notice it becomes pCylinder2 and pCylinderShape2. Also, the reason the creation node is called poly... yeah, confusing, but it is to distinguish it from the transform and shape nodes I think.


Last edited by stwert; 22-01-2011 at 05:40 PM.
# 15 22-01-2011 , 07:33 PM
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Okay, now let's take it a bit further, pre-empting the next question, why have two nodes, "transform" and "shape" when only one would make more sense. Well, what is a transform node? Ask the question, what is a group node. Create a group (Ctrl+g) and check its attributes. It looks exactly like a transform node. So a group node is basically a transform node, and so a piece of geometry is basically a shape node just grouped with itself so it has transform information.
Also note that you can delete only the shape node, and you'll have an empty node in your scene that you can move around, rotate scale. So... I guess having both shape and transform nodes is important because transform nodes exist independently (like in the form of group nodes) and shape nodes simply give content for the group/transform nodes.
Just FYI. Hope I'm not being confusing.

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