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11-03-2012, 09:25 PM (This post was last modified: 03-14-2013 05:54 AM by probiner.)
Post: #1 The POLE
This thread is a replication of the salvage fom Not all posts are replicated, and some were snipped (missing urls, etc). The author and number of the post are in the title of each post. The goal of such thread is to provide easy access to these contents and allow them to be discussed, rather than just observed.

Kudos to vbob and madseeds for the backups.

Posts' content with forum formats, images and urls in place can be found in this pastebin. Feel free to replicate them anywhere.

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11-03-2012, 09:26 PM (This post was last modified: 03-14-2013 06:14 AM by probiner.)
Post: #2
#1 SomeArtist
[Image: atri1yydp9.jpg]

Have a careful look at this Triangle image because it holds the key to mastering Sub-D modeling. Triangle is the smallest element in a 3d model and by knowing how to solve Triangles you will make a big leap forward as a 3d modeler. In fact, once you're through with this thread you'll be modeling like Bay Raitt! (No kidding!)
But first we must understand poles and before you read on make sure to forget what you have learned about Poles! Here is another way of looking at it.

The (E) and (N)

Poles in general are not good for your Organic models however, you cannot avoid the 5 and 3 edges poles and instead of being afraid of them why not try to understand them? Many beginners cannot advance to the next level because of this blockage (poles) and so they tend to fear them and then Topology becomes difficult and they fear that too. The 5 and 3 edges poles are very special poles, 6 and beyond are not special so you can ignore them completely and since there are only two special poles we're going to give them names.

The E(5) Pole
[Image: be9degj3.gif]

The E pole is actually an “Extrude Pole” (E for short). When you extrude a Quad you will get 4 Es!
[Image: cecube5ownv1.jpg]

When you extrude for the mouth, eye and ear you'll get 4 Es each. When you extrude for the arm/leg you also get Es.
[Image: dehead3xquk1.jpg]

The N(3) Pole
[Image: en5mwda3.gif]

When you model a nose you'll get this 3 edges pole and there is no way you can remove it because if you do then that nose will not look like a nose and so it was meant to be there (Keep that in mind).
[Image: fnose8zeml1.jpg]

I call this 3 edges pole “The Nose-Pole” (N for short). The Nose is a very special case in that you get “E” and “N” next to each other, I call this the “EN” case. This “EN” situation will surfaces once you get into detailing like the nose here. If you remove this “EN” you will remove the detail for the nose and in the image above I have separated E and N with a Loopcut (more on this later).
[Image: gnose9arzb4.jpg]

Now why is the talk on Poles important? Poles control how things flow in your topology, have a look at the image below and I'll get back later.
[Image: hheadflow7fkyo8.jpg]
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11-03-2012, 09:48 PM (This post was last modified: 03-14-2013 06:15 AM by probiner.)
Post: #3
#6 SomeArtist
The talk on poles will helps us to understand flows and smooth/bumpiness of our meshs. So far Flow was brought up so I'm going to continue with flows then later I'll talk about smoothness and bumpiness.


The Es cannot be eliminated but the Ns can be. Since we can't really eliminate poles in general what we can do is hide them and eventually they will be gone and that is the trick.
[Image: atrick3vj.jpg]

A good example of this is the NPoles for the forehead and the back (if you started with a Box that is). For the forehead you hide it inside the eye and for the back you hide it inside the Ear. You do it via a method called “UnPole” which I will go in-depth later. Now, just because you can remove NPoles doesn't mean you should do it! Some Npoles are meant to be there like the Nose and when you get into detailing the muscles for the human body you will get a lot of NPoles/EPoles since Poles control flows. A model with complicated flows will have a lot of Poles and vice-versa.

I have argued with a much more experienced modeler about the Npole for the forehead. He told me having the Npole there gives better control for the forehead. Now think about that for a moment.. we all know that Poles make our meshs bumpy. Better control with a price and that price is “Bumpiness” and we all know that the forehead is not 100% smooth! (Underneath is a skull) So yes, you can leave the Npole there for better control of the forehead. Whether you should leave that Npole there or not is up to you. To say “Should I remove it” is the same as saying “Can I use Ngon?” And the answer is always “If that is what you want, then that is what you must do. There are no rules.” The picture will get clearer once I talk about smooth/bump later.

[Image: bcircular3yl.jpg]

When you extrude a poly you instantly created a circular flow (dark orange in image). In some cases it's good to have a circular flow with Es on the same lane (yellow), however in the case of a human head it's very bad!
[Image: clane5vs.jpg]

(A): According to the screenshots of human head from professional artists in my collection, this Loop for the mouth is important. You cannot achieve this loop with both Es on the same lane so the trick is to move the upper E to the left lane (B). The next time you see both Es on the same lane you can be sure that it will form a Circular Loop.. If you remove (shifting it elsewhere) the upper E you will break the circular Loop like you are seeing it here.

[Image: dlanedown4if.jpg]

Instead of shifting the upper E I shifted the bottom and this is the result. Pay attention to poles because they are your guide to better flows!

Quote:when you extrude a quad you get EN not just E
Nice observation!

There are much more to Poles than I first thought. For example, when you extrude a POLY that has N pole as one of its corners, you will convert that N into nothiing (no pole)!

[Image: erep4nz.jpg]
Note: For the first post in total there are 8 images and for this one there are 5. Just wanted to let you know in case they're not showing.
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11-03-2012, 09:50 PM (This post was last modified: 03-14-2013 06:15 AM by probiner.)
Post: #4
#9 SomeArtist
Earlier I said that when you see two Es on the same lane you can be sure that it will form a Circular Loop. Here are two more images (below) to confirm that observation.

[Image: aconfirm2ks.jpg]

Pay attention to the Es because by shifting one back and forth you can achieve “predictable” flows! There are no guesswork here.

[Image: beguide9fj.gif]

You can use this dot/curve image as guide.


Earlier in the “Form” thread I mentioned the Key and Fill concept and how you can use it in anything that you do. Key-XXX/Fill-XXX, where XXX can be anything and in this case they are Key-Loop/Fill-Loop. When you look at Edgeloop references out there what you are seeing is a bunch of Key-Loops for you to Fill in.

[Image: ckeyfill8hq.jpg]

In a KeyLoop stage Poles are close to each other and when you add in the Fill(s) they start to fall apart after the tweak (It's difficult to keep them together after the Fill(s)). During the fill stage you can increase the resolution for the KeyLoop that you're working on and while doing so you can move a specific pole away to a place where you think it belongs. If you have been collecting wireframe references now is a good time to open them and observe. Immediately you'll learn that all modelers are different in the way they place Poles.

[Image: dplacepole4mo.jpg]

There is no right or wrong but the general rule is: Don't put them in areas that deform and in the image above (cyan dot) I put it there because I want it there. When I get into deformation and that area doesn't deform well then I will do something about it but for now I will leave it there. I leave it there because I have looked through many wireframes and I see that pole there... somewhere there and it doesn't have to be exactly where.

If you're still afraid of POLES then have a look at this thread by Glen: BREAK THE SYMMETRY

In that thread Glen explains to us that the human faces are not 100% perfect. Why are we forgetting this fact? The human faces have dimple, crack, holes and it's never perfect. Now just imagine that poles can be used to represent these features. Hey, if someone say why you have a lot of Poles in your model, just make up a story and say that this character had a car accident!
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11-03-2012, 09:52 PM
Post: #5
#10 Toontje
Man... I would be honored to have you as a neighbour. Your analisys of topology is better then whatever I've

encountered out there.

If I learned something is to take a step back and analyse too what the basics are of edge loops and what the functions are of the poles in addition to what you already explained. So permit me to present my findings (and please don't hold back any critiques) Smile

I found that there are 4 ways in which poles are produced on the mesh:
1) extrusion
2) spin quad/ spin edge
3) rip (help me out here, by lack of a better term. It is wath the V key does in Blender.. but I explain more in detail later)
4) Knife tool

I also found out also that edgeloops may overlap on different ways without interfering with eachother


After you invoke the extrude command, you may pull a 'limb' out the mesh, or confirming the command right away, leaving an edgeloop on the mesh.

[Image: Polepg1_Page_10_Image_0001.png]

Something was said in the affect that a pole can not be elliminated? could do it like this:

[Image: Polepg1_Page_11_Image_0001.png]

After the cuts, you are left with 3 pairs of triangles that can be merged into 3 quads. The result looks a little funky, but if you elliminate another ADJECENT E pole, you are left with a C-loop

[Image: Polepg1_Page_11_Image_0002.png]

Edgeloops can coexist. So in this way you don't have to be afraid that there might be some dire consecuenses that edgeloops you create might disrupt edgeloops that are already present:

[Image: Polepg1_Page_12_Image_0001.png]

As you can see, loops can touch eachother, intersect or be a part of each outer loop, which is cool. So this means that you can form your eyes loop, mouth loop and pull a nose loop that intersect the mouth (or mouth-nosetip loop) without a hassle. The nose loop could be converted in a C-loop with the technique I mentioned above.
That's it for today...I will pick it up tomorow Tongue
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11-03-2012, 09:52 PM (This post was last modified: 03-14-2013 06:15 AM by probiner.)
Post: #6
SomeArtist #14
Since C-Loop was brought up.

[Image: Polepg2_Page_02_Image_0001.png]

This incomplete head was modeled entirely in Blender from a BOX and it used the CLoop topology. If you're a beginner I highly recommend that you start with this Loop because it's easy and can save you a lot of stress since you're learning best of all you can create amazing result! As you can see from the image above, I have gone far and still using that Loop. Now that I understand Topology after using the Cloop I can branch to other Loops or even invent my own. Here is the Key:

[Image: Polepg2_Page_02_Image_0002.png]

When I look at a wireframe I look for Poles because I can copy the topology using Poles as guide since Pole(s) define a Topology, just look for the Poles. Last, do not be too obsessed with Topologies just read the SUB-D Primer and you'll learn that having a clean/kick-arse Topology doesn't mean it will deform correctly during animation. However for still images/Zbrush sculpting a CLEAN MESH is best. When you get into deformation and things doesn't work out just use the knowledge here to change/adapt which is better than trying to learn all the topologies that exist out there.


[Image: Polepg2_Page_03_Image_0001.png]

This model is now 100% Poleless thanks to shahar2k at Wings3Ds forum who have shown me the trick and here's the direct quote (for Wings3D):
shahar2k Wrote:a little experiment to try,
1 - take a model made out of 100% quads (any model that is smoothed once already for example)
2 - set all the edges to "hard"
3 - smooth the entire model once,
4 - select all "hard" edges and delete them,
5 - select all "isolated vertices" and delete those too
The Key idea is to subdivide your mesh and keep the subdivided version while deleting everything else. All the EPoles will be converted into Ngons and all the NPoles will be converted into Triangles! To move Ngons around is to move Epoles around and to move Triangles around is to move Npoles around which is one way or you can do it directly after you subdivided. Once you have a poleless model you can start your Poleless quest, Bay Raitt anyone?

Poleless conversion
Epole --> Ngon
Npole --> Triangle

I don't know why anyone would want to do this and I guess the only way for me to find out is to get into deformation later. The good thing about a Poleless model is that you can select an Edge's EdgeLoop and it will run all the way from start to finish, nothing will be in its way (No poles).

Note: Don't try this in Blender

A Demonstration

[Image: Polepg2_Page_04_Image_0001.png]

Here is a very short and powerful demonstration before I get to the actual Technique (next post).
Take a look at (A) and what you'll see is the Loop I created on purpose. I want that Loop there but I also want another one, look at (B)-Yellow Highlight. From what we know, 2 Es on the same lane will create a circular flow and so I put a pole as pointed by the White Arrow.

[Image: Polepg2_Page_04_Image_0002.png]

Now I have it! BUT there is a problem. Look closely and you'll see that the original flow got broken (green) so the question is: How do I create a secondary(B) flow while keeping the Primary(A)? The trick is to think one step ahead.

One flow cannot go in both directions! You cannot have one flow that go LEFT AND RIGHT. To do that you must split the main flow into two.

[Image: Polepg2_Page_05_Image_0001.png]

So that one is reserved for the main flow while the second one is for, whatever you want.

[Image: Polepg2_Page_05_Image_0002.png]

Instead of splitting it into two I made 2 fills which gave me 3 flow.

[Image: Polepg2_Page_05_Image_0003.png]

As you can see, there are no guesswork here.
Quote:Any chance of a look back there?

[Image: Polepg2_Page_06_Image_0001.png]

modeling the nose is easy with Poly-by-Poly and for a box I still haven't figured out a logical way yet. If you're looking
for the best
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11-03-2012, 10:06 PM
Post: #7
#18 SomeArtist
Quote:I feel like I'm Hijacking this thread

Hijack means "Contribution” and you have just turned yourself into a 3d Organic Scientist, good for this thread. I'll get
back to the topic later.

Quote:we really should stop refering to face loops as edge loops... face loops are edge rings converted to faces
Somehow we (as a whole) need to come up with a clearer explanation for those that are starting out.

[Image: Polepg2_Page_11_Image_0001.png]

Which one is really edgeloop? A, B or C. The majority believe that B is a better example of EdgeLoop.

Redefining Edgeloop can be tricky because of the context. For example, a passionate Organic modeler might say that Edgeloop is “MuscleLoop”! If this organic modeler spread this idea then it will be a problem when you start to model trees or Machines since they are not Organic so you can't really say “MuscleLoop” when you're modeling a Building since buildings don't have muscle.

Now if you use SUBD algo that gives no pole then (A) in the image above would be a true Edgeloop since edgeloop in a poleless model would run from start to finish but when you use SUBD algo that gives Pole then (A) would not be a true edgeloop anymore since a pole would stop it completely. To pass the pole is to use the Ring as Loop and Pole would not stop it as seen in (B). The problem with (B) then is Ngon, having Ngon in (B) would stop that PolyLoop whereas having a Pole in (A) would stop that EdgeLoop. So to go pass all the Ngons/Poles is to go with ( C ) which is inside a PolyLoop(B).

Since the Edgeloop inside ( C) is actually inside a PolyLoop does that not make (B) a better definition of an EdgeLoop?
I know that an Ngon would stop that Loop but we all know that Ngons are bad when it comes to PolyLoop modeling so (B) fits the concept perfectly. By choosing B as the concept we can make this concept even better with the Key and Fill. If we choose to go with A or C then the Key/FIll would be gone and learning modeling would be difficult.

Some people prefer to listen to Programmers because they are the one that coded the code but we must keep in mind that programmers are not artists and vice-versa. It's all in the context and we should pick one that makes learning easy! Muscles are not thin lines, they are thick and (B) would be the concept I go with.

If we choose to leave everything the way they are then we can use clever concepts when we are referring to them. For example, if I were referring to (B) I would say: PolyLoop. © would be EdgeLoop and (A) would be EdgeCurve.
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11-03-2012, 10:08 PM
Post: #8
#19 Layer01
SomeArtist Wrote:If we choose to leave everything the way they are then we can use clever concepts when we are referring to them. For example, if I were referring to (B) I would say: PolyLoop. © would be EdgeLoop and (A) would be EdgeCurve.

your absolutly right, we need a unified nameing scheme, otherwise everyone is just going to get confused.
faceloops sound better to me than polyloops, as we already talk about faces, vertices and edges in all modeling apps to describe the three basic elements.
But maybe we need new words to help us describe what we are talking about?
say maybe instead of (B) being a faceloop (cause some might argue that it doesn't loop back and close itself) maybe we could instead have the name reffer to the edge that runs the faces.
maybe O loop
like this:

[Image: Polepg2_Page_13_Image_0001.png]

i say "O" because if you look at the edges around the faces they form a closed (in this case bent) O shape...seems to me that this sort of visual naming makes sense as its clear why its called that, and even a newcomer can see it and undersand.
as for the edgecurves...that name makes little sense to me, i see its an edge but nothing to make it more a curve than say a Cloop. its just not imediatly logical.
however it seems to me that its main feature is that it's adjacent to Poles, or is connected/stoped by poles, so it'd make sense if the name invoked this nature..say poled edge, edge pole, pole curve?

[Image: Polepg2_Page_13_Image_0002.png]

however © makes sense, its an edge..and it loops, all or part of the mesh. this sort of logical naming scheme is what we need.
just look at exsisting names, box modeling..reffers to a modeling style usualy started with a box...poly modeling, a style that involves building the mesh poly by poly...all easy to undersatnd cause the name is linked to the concept.

of course making new words can be tricky, but if they make sense then people will use them, for example Epole and Npole makes sense and i use them all the time now to describe what i'm talking about.
not saying my names are the best or anything, just putting forward some suggestions.
though for the record faceloop and edgeloop work for me.
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11-03-2012, 10:09 PM
Post: #9
#21 & 22 Tonntje


Today I'll be talking about mesh ripping. I don't know what the command should be called, or if there is a similar command in another package than Blender. If anyone has a better name for it, I'm interested.

So, what's up? The tools that I'm explaining here are tools that have an effect on the topology because they produce poles. I didn't quiete master the ins and out of this technique, but let me present to you what I found out so far.

What is mesh ripping? With this tool (Vkey for Blender), you rip the mesh open by pulling at a vertex. In Blender you should fill the hole it produces yourself.

[Image: Polepg3_Page_01_Image_0002.png]

The mesh above was ripped open at the upper N-pole. After that you may want to fill the resulting hole. In these scenarios I will fill the hole.
So, like spin edge, rip mesh produces a pair of N-poles and E-poles. Like I said before, the direction of the faceloop (I agree on the terminology too) is determend by the N-pole.

The resulting hole stands out like a diamond in the mesh. If you encounter such situations, and you a meaning to eliminate poles, just merge those N-poles together to get rid of all the neighbourhing poles (thus effectively reversing the mesh rip).

After a spin edge, you are left with pair of poles opposing eachother diagonaly. With mesh rip the poles are opposing verticaly or horizontaly.
So far I have found these uses for mesh rip (topology wise that is):

1) Moving E-poles around (YES Big Grin )
2) Creating C-loops

Because of the lack of Ngons support in Blender, you have to manualy complement the mesh ripping operation by using the cut tool and merge triangles into quads. But nevertheless, mesh rip is a very powerful tool.

First, Creating C-loops:

The rip mesh tool is very flexible in conjuction with the knife tool. Depending on the method, you are left with a single C-loop, or with a mirror pair of C-loops.

Creating a single loop:

[Image: Polepg3_Page_02_Image_0001.png]

And after the cut:

[Image: Polepg3_Page_03_Image_0001.png]

This was a very minimalistic loop because I ripped at only one vertex.


If you want to make a much wider loop, you must rip all the vertices in a row. You need to use the knife tool to obtain the face loop. Depending of how you cut the mesh, the results will vary.
To obtain a single broader face loop:

[Image: Polepg3_Page_04_Image_0001.png]

Here I'll cut before I fill the hole, else there will be triangles in the corners

[Image: Polepg3_Page_04_Image_0002.png]

And then after filling the holes and cutting (and smoothing) you are left with one C-loop (by the way: I assume that C-loop means C shaped loop and not closed loop).

[Image: Polepg3_Page_05_Image_0001.png]

There is a number of ways to make a number of wacky face loops/ edge loops with this method, but i suggest to keep it simple because simplicity and predictability is the name of the game here.

Lets try to make a a closed loop like in a extrusion:

[Image: Polepg3_Page_05_Image_0002.png]
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11-03-2012, 10:10 PM
Post: #10
#26 Wasamonkey
MarkFeathers Wrote:As far as my research has gone (I can't find the main site that had the info on it but, I'll keep looking) 3 edge poles are not really any kind of issue. It's the 5 or more edge poles that cause problems because of pinching and unpredictable results when they lay on a surface that gets animated.

hi mark, 3 point poles are simular to tris and 5 edge poles are simular to 5gons when using catmul clark, which seems to be the most popular for sub-d
the biggest problems with both are texture warping anf pinching and such in areas with deformations it's when we step into these aspects that we start running into problems now why is a tri or 5gon worse than their respective pole counter part?

as for my own ideas of why is it mainly has to do with more even surface tension across an individual face
so when we smooth we see less adjustment to the faces to accomidate the cuts, thus leading to less distortion, but either can be bad in the wrong spot

let me bring something over from my spline modeling experience with splines. Your pretty much forced to work all quads, and as few poles as possible one thing I learned was placing things that caused creasing and pinching in areas where that happens naturally on a real subject.
Like puting geometry that you know is going to crease in the armpit one this will help the model look a bit more natural when moving as the creases just happen, and it allows you to terminate splines that would have made manging the model more difficult

spline based character topology is'nt perfect by any means, but is well worth the study as there are some common pitfalls and techniques that carry over to sub-d

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11-03-2012, 10:11 PM (This post was last modified: 03-14-2013 06:16 AM by probiner.)
Post: #11
#27 Someartist
For this post I'm going to talk about the technique since people are waiting for it then later I'll respond to the posts before this one.

Earlier in my first post I showed you the Triangle image and told you that it held the key to mastering Sub-D modeling.

[Image: Polepg3_Page_09_Image_0001.png]

The top row is what you have been living with and the bottom row is the UnPole technique. Combine this technique with Spin Quad (plus the knowledge on Poles) and you have just mastered SUB-D modeling! Here is another way to solve the Triangle.

[Image: Polepg3_Page_09_Image_0002.png]

Keep in mind that I did not invent any of the above I am only giving it a name and raising awareness (especially the bottom row in the first image). Now that you can solve Triangles you can turn a messy mesh into a good looking mesh! First let's look at the SpinQuad and Unpole.

Note: You need to know the above if you're planning to model in Blender since Blender produces a lot of Triangles.


SpinQuad is a very powerful technique that can change a flow in an instance. All you need to do is select two faces and Spin them.

[Image: Polepg3_Page_10_Image_0001.png]

There are two problems to this technique and they are:

1: The mirror effect.
2: The NPole!

These two problems can be solved by unpoling the Npole and once that Npole is gone the rest will be gone.

[Image: Polepg3_Page_10_Image_0002.png]

I look at Unpole as a technique to clean up the mesh (beside shifting poles).

There are two ways to create/change a flow and they are:

1: From a pole perspective
If you want a pole at a specific location then do not use SpinQuad since it's difficult to visualize the result in your mind. By knowing that two Es on the same lane will create a Circular flow, then it's logical to do it from a pole's perspective.

2: From a SpinQuad perspective Use SpinQuad when you don't think much about Poles. Sometimes it's logical to use SpinQuad over UnPole and vice-versa!

And last you can combine these two together. I'll get into Shifting poles next for now try and open one of your messy meshs and see if you can look at it from a Triangle perspective.

Though act to follow. SomeArtist, I feel like one of those small fishes swimming along with the shark. I will present to you some technique to move poles around. One can be done with the Break command, and the other can be done with the Spin Quad command.

First the break command:
Let us take a standard circular egde loop/ face loop as the starting point.
A break normaly produces 2 E-poles. In this we have to break the mesh (/vertex) at a specific location so you are not introducing an extra E-pole. The logical place to do that is where the N-pole is located at. But not only you'll shift the E-pole, but the N-pole will come along for the ride. But this technique can only be done when there are no 'fill loops' present, in otherwords, the E-pole and N-pole are in direct contact.

[Image: Polepg3_Page_11_Image_0001.png]

As you can see, E-poles that once was on the same edge loop, are now on different edge loops.

[Image: Polepg3_Page_12_Image_0001.png]

Using Spin Quad:

There is a lot of possibilities here making the spin quad rather flexible. As stated before (I think), the spin quad should be used more as a tweak tool. By moving poles around, you have total control over the flow of the loops. With the spin quad, if you spin an edge that is connected to a N-pole, you'll get a pair of quads that shares two edges. This will look like two tris, but don't be fooled and convert it into a quad.
Let's start from this situation:

[Image: Polepg3_Page_12_Image_0002.png]

This was achieved by performing a spin quad.

SomeArtist already showed an inginieus method to eliminate one pole by unpoling the N-pole. I guess this can be done for any N-pole. One possible disadvantage is that your mesh will become denser.

In the image above, you have 2 loops that are joined at the hips. Here I shall show how to move the E-pole around and thus effectively seperate these two loops. This method can be repeated to further drift these loops apart.

(continued on next post......
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11-03-2012, 10:15 PM (This post was last modified: 11-03-2012 10:16 PM by probiner.)
Post: #12
#29 Tonjee
[Image: Polepg3_Page_13_Image_0001.png]

In the image above there you can see those two loops that are joined at the hip. To seperate them you can spin the green of blue edges. Don't spin the red edge, otherwise you are just reverting to the original situation (no loops) or if you spin twice both loops will flow in a oppisite direction.

The green loops are easy. When you spin it, the loop will seperate and drift diagonaly away. You may keep repeating untill the loop is at the end of the mesh. Or you can unpole it or collapse it to get rid of it. Maybe it is not apperant in which direction you should spin this quad/ edge. Just visualize that you have to spin it so the edge will allign to the horizontal adges outside the loop. So in this scenario you should spin the upper right green edge once counterclockwise and the result is this:

[Image: Polepg3_Page_14_Image_0001.png]

(To be continued)
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11-03-2012, 10:16 PM
Post: #13
#30 SomeArtist
I can actually lose my breath by trying to show you all the combinations so what I'll do is show you the key ideas then from there you can experiment to find out. I might only show you one way but keep in mind that there are many ways! It depends on how you want your mesh to flow and how you look at solving the Triangle.

[Image: Polepg3_Page_14_Image_0002.png]

When you want to merge two Es onto the same lane all you need to do is collapse the edges.

Moving the E (Rotating)

An E Pole has 5 edges and all you need to do is take one of the 5 edges and rotate it, that is in theory. In practice what you do is delete it which will remove the E pole and you are left with an

[Image: Polepg3_Page_15_Image_0001.png]

Ngon. Rebuild the Ngon and there you have it...

[Image: Polepg3_Page_15_Image_0002.png]


[Image: Polepg3_Page_15_Image_0003.png]

The combinations are endless once you turn a Quad into a Triangle. Look below:

[Image: Polepg3_Page_16_Image_0001.png]

The same key idea can be used in reversed:

[Image: Polepg3_Page_16_Image_0002.png]

Toontje brought up SpinQuad and there is something interesting in it when you compare it with the Wrinkle technique which is used for wrinkle effect but it can also be used to create flow(s).

[Image: Polepg3_Page_16_Image_0003.png]

The difference is in the poles. Also, earlier I said that the Spin Quad are not logical well, after looking it a little closer I can now say that it's very logical!

[Image: Polepg3_Page_17_Image_0001.png]

When you about to an spin edge or quads keep in mind that the green dots will be converted to Epole and that the Orange dots will be converted to Npoles.
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11-03-2012, 10:20 PM (This post was last modified: 11-03-2012 10:28 PM by probiner.)
Post: #14
#31, #32 and #33 Toontje
OK now, I will continue with my previous rambling Wink

In my previous post there is a matter left about the blue edges. This has to be spun COUNTER CLOCKWISE always. The end effect is that the loop drops one position/ row. But in between the spin quad action will look like a mess. Delete the lone vertex.
What this realy is, is two quads sharing two edges. By deleting this vertex, and filling the hole up, you are converting these 2 quads into one quad.

[Image: Polepg4_Page_01_Image_0002.png]

Ofcourse after smoothing and stuff the result will be:

Indeed you might have noticed only a vertical shift. You can shift it verticaly too by spinning another edge. But like SomeArtist said, I can lose my breath explaining all possibilities. As long you get the picture.

Next I'll explain the cut tool. I've discovered that the cut tool gives very unexpected results. You cannot just simply cut away in your mesh and expecting a nice edge loop. But I found a method to correct that using the magical but less understood Spin Quad again. With this method, you are left with a totaly clean face loop that you can use for a number of things like fine detailing (veins and such)

But I'll continue later.....

This one is very tricky and I doubt that someone discovered the fundemental flaw of the cut tool, otherwise it would have been mentioned long ago. That is perhaps why I was never able to define muscle shapes with the cut tool in the past.

I gather I don't have to explain what the cut tool does. But I don't know if it works the same for all packages. But here it goes:

With the cut tool you can cut faceloops/ edgeloops into your model. Most of the time you hear that you can model small detail like veins easily with the cut tool, so let's do that.

[Image: Polepg4_Page_03_Image_0001.png]

After this I'll smooth it a little and select the centre edge loop. The centre edge loop is not really a continiuos loop because it terminates at each N-pole.

[Image: Polepg4_Page_03_Image_0002.png]

Lets pull this edge out to form a nice vein or something

[Image: Polepg4_Page_04_Image_0001.png]

So it looks like a nice method to add detail or loops to a model right?
First of all remember that I've said how face loops got bent? They bend at a N-pole! All face loops layered after that one will get bent by the N-pole!

Let's take a closer look at the cut mesh:

[Image: Polepg4_Page_04_Image_0002.png]

Observe how the face loop would get bent at the N-poles. Indeed there is a problem here: the location on where the face loop would bend alternates on both sides of the highlighted edge loop. This will result in multiple face loops running ammock on the surface of your model. When you try to use the edge loop cut you'll see that the edge loop cut will snap unexpectedly on various location on the mesh.
Notice also that the bending side alternate at a moment that the cut changes direction on the clock. So if you keep cutting in a C-loop or closed loop (like a normal extrude) or keep spiraling with the cut tool, there won't be any side effects. But as soon you make a S-like cut then you'll have this problem.
So this explains a) Why nobody never experience problem while cutting simple loops (like eye loops, nose loops) early on when box modeling and b) that's why you mesh gets messy if you want to cut details on your surface.

Here I'll colour the face loops that are produced by this cut operation:

[Image: Polepg4_Page_05_Image_0001.png]

The knife tool was supposed to be some kind of wonder tool, a modelers dream, but here you see that it will reap havoc on your mesh leaving you with a heap of ugly and useless face loops.

But there is an elegant cure thanks to the obscure... or better said our hero: Spin Quad.

To end this post I want to remark that everywhere and everybody is talking about edgeloops. But in my experience I see that the face loops is the dominant factor in terms of topology. Heck, every top modeler seems to highlight face loops in their model even though they are wrongly talking about edge loops.
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11-03-2012, 10:21 PM
Post: #15
#33 Tonjee
Luckily there is a simple solution to this problem. Remember that things go wrong at the moment the the N-pole bends the loop on the other side of highlighted edge loop? Well, let us identify those N-poles that causes the problem.

[Image: Polepg4_Page_06_Image_0001.png]

Those edges that are blue should be spun. If the edge to be spun was preceded by a counterclockwise direction change in the edgeloop, then it has to be spun clockwise, if it was preceded by a clockwise turn, then spin it counterclockwise. HUH??? OK, for example, the first N-pole to be spun in the image above was preceded by a "L" turn. When driving on this L-turn you are making a counterclockwise move, so the first problem N-pole on the route should be spun clockwise. And vice versa.

When you spin those edges you have to perform the same corrections I explained a few post back. That is to delete the lone vertex and then fill the hole and smooth afterward.

[Image: Polepg4_Page_07_Image_0001.png]

And the result is only one face loop. To pick up where the problems started: Let's make a vein. Now we have to perform an edge loop cut.

[Image: Polepg4_Page_07_Image_0002.png]

Compare this image with the image in the previous post. They almost look the same, but this edge loop is truly continious. It doesn't bump against poles along the way.

[Image: Polepg4_Page_08_Image_0001.png]

The topology/ mesh here is clean. Compare it with the previous vein example. The differences is hard to spot? Just follow the highlighted edge loop. Follow each little segment. On both sides of a segment there supposed to be one quad on either side. That is the case at the second example. But check the first example: in the problem areas, 2 segments of the edge loop share one quad, making it look akward.
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