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Stephen: Hi and welcome to 3dmotive.com.
My name is Stephen G. Wells, and I'm a senior character artist.
In this quick tips and tricks tutorial we will take a look at
retopologizing for animation.
Right now this is the Topogun interface.
Topogun is a really outstanding retopology program.
It's one I recommend to all my students.
It's not very expensive, so usually can fit pretty much everybody's budget.
I'm going to go ahead and use this old model of a caricature basketball player.
I've used it for other tutorials but it just comes in handy.
It's a really great model to show off some of the stuff
that we're talking about.
If I zoom in a little bit,
I'm going to go ahead and turn on ...
I actually built this really quickly
to illustrate some of the things that I see students do.
Actually I see junior modelers do this sort of thing as well.
This is the main body obviously,
it's just the front and the arms and then the face.
Now if you look at the face, if I go and take off the net per se
you can actually see, okay this follows -
if you had artwork that you were following,
obviously this is following the geometry of whatever the 3D art might be.
You've got your polygons, you've got your edges, etcetera
and technically, I see where somebody could build this
and I see this all the time with the students.
Like here's where the eyes are, here's where the mouth is.
If you look down into the body,
they don't tend to have a lot of polygons in the body.
Have almost none on the shoulder.
Like one edge loop for the elbow
and then a whole bunch of edge loops for the forearm.
Never quite understood that one
but the thing is for animation purposes this just doesn't work.
I mean if you were to try and bend this arm forward
it would stretch all the polygons
or actually make the polygons collapse on themselves.
Obviously, if we're going to try to make the eyes blink
or the mouth move in something like this,
it just isn't going to happen.
I'm going to go ahead and do a quick screenshot.
In Photoshop, I've brought up the screenshot of this particular mesh
and what I want to show you,
I'm going to go ahead and just create click layer.
There we go.
I'm just going to grab like a red color.
The problem is, is here's where the eye is.
Okay and here's obviously between the lips.
There's no way that this thing can animate
it can't blink, there's no way that this is even built so that it can absorb
any of the deformations the mouth might want to do etcetera.
Because we're basically looking at straight up and down box modelling.
This sort of thinking.
We're doing this bed, it just box modelling
which of course is the basis for pretty much any model.
Any model pre-looked at from a box modelling standpoint
it's basically a bunch of horizontal, vertical intersections.
The thing is none of this in here would work for any of our purposes.
I'll go ahead and just grab another color.
I need to see something more like,
let me go and turn this off.
I want to see something more like
and I'll get a nice, bright color.
I'll do like a yellow, so you guys can see this a little bit better.
I tell my students think in terms of rubber bands.
Rubber bands are very flexible.
Of course the main stay of rubber bands is they're circular.
They basically have a circular ...
Oops, hold on, sorry about that.
They basically have, it's circles.
Okay.
Once you've got the base circles, a couple of edge loops of that
and you could do some in and around the mouth in here, etcetera.
Once you've gotten that far enough, you can then start.
Now I see some people will turn out, and it will extend
this type of curve all the way out.
I will as well for the most part.
There will be times when I'll build out to a certain extent
and then we'll say, once I've got in this couple of edge loops around here
then I actually just do connections in between, okay.
Really just depends, I try to keep as many edge loops as possible
but you have to understand the cheek areas aren't what's animated on the face.
The mouth is what's going to be animated.
The chin area, etcetera depending on how stretchy
or how cartoony you want the jaw to be, etcetera.
Obviously, around the eyes are going to be very animated.
If you look at any of the 2D animated movies or even the 2D cartoons,
the cheeks don't do a lot of movement,
the foreheads don't do a lot of movement,
the noses, sometimes don't even do a lot of movement.
The eyes often will blink but certainly around the mouths
there's going to be some serious deformations.
Around this, let's do a quick screen show to this.
Then again you can see that in this case,
it's not that they're doing anything wrong here.
They're really technically not.
That's still enough of the cross hatching,
that wouldn't be much of a problem in the body.
There's not enough here and here because this is the joint areas.
There's certainly not enough here.
Here in fact, we could actually lose some.
We don't need this many here.
I mean this can almost be one edge loop starting from here,
one in the middle and then one near the end.
Then make sure we got enough here
for what the wrist is going to be like another split.
You don't need like any of this, you can just cut them down.
You have to look at, again the idea is it's rubber bands.
Where are the joints, the joints are what are important.
They'er the ones that need to get that elasticity.
That's where we need to make sure we have more edge loops
because that's where the models going to bend more
and it's going to look good with textures, etcetera when its animated
without stretching of the textures and certainly no collapsing of the geometry.
Of course depending on the rig, that always helps.
If you have good rig, you have good edge loops,
you're going to get a good modelling game.
If we go back in the Topogun,
I would go ahead and take a look at redoing this.
Again based on what we've just discussed.
I'm going to go ahead and view our reference again.
In this case with Topogun - by the way if you're not sure
how to use Topogun or you do know Topogun
but are a little unsure how to control it,
it's the same sort of controls as Maya.
I can left-click Alt to rotate around,
middle-mouse Alt to [pan],
right-mouse Alt to zoom in and zoom out.
It's really that simple.
The important thing is we need to look at this as again rubber bands,
where are the rubber bands going to be?
Again, the mouth, around the eyes, going to make sure that's going to count.
With Topogun I'm going to go ahead -
when Topogun usually opens up, you usually have this over here.
Unfortunately I don't have enough real estate to be able to film this etcetera
so I actually have to move this over a little bit.
When you open up Topogun this will be on the same side
but I'm going to go ahead and just get into my -
this are the edit tools, so this is when you want to grab your vertices,
edges or phases.
This is the create tool, this is what we'll use to create our polygons with.
The draw tool we can also create polygons with
but it's a little different than just the simple create.
I tend to use just a simple create,
it's quicker, it's easier, it's more direct.
This is our bridge tool where we can turn around
just bridge the gap between polygons
and you'll see what I'm talking about in just a second.
Let's go ahead, and I'm going to just grab these phases
and I'm going to hit delete, and delete all.
Just going to go ahead and make sure we're deleting all of them
and we're going to get the edges and the vertices.
There we go.
Oops, I got some here, just want to delete those
and over here, delete.
Okay, again like we talked about,
we want to make sure that we're looking at rubber bands
when we're working on this particular model.
What I would suggest you do is like start with,
say a center point on the mouth for instance.
We're just going to create ...
Now I'm only going to do one side
because the beauty of this is we can turn around a mirror.
As you can see, I'm keeping what will be
and I'm just left-clicking, left-clicking, left-clicking.
If I hold my Ctrl key down,I can snap to that vertices.
Here's the bridge tool, I'll just have to select over an edge
and you can see it wants to fill it in for me.
I'm going to do that really quickly.
Oops, there we go.
All right, let me just do a quick hiding on the reference.
Right off the bat you see that we're going for this flow, you see that?
I'm actually going around the mouth.
So we can continue something like that by, I can snap.
If you hold down your Ctrl key, you're always going to snap
so I'm going to hit snap and start this off.
We'll go for another one over here.
I'm going to use my Ctrl key to snap again by bridge tool.
Okay, let's just go and select that.
I can grab all of these vertices right here
and there's a button here called zero symmetry.
This is a symmetrical model, all I have to do is hit zero sym
and it will clean it up for me, right there, see that?
Nice and neat, simple.
Let's just do quickly around the eyes or and eye,
just so you guys get the idea of where I'm going with this.
Want to go ahead and go 3, 4, we'll just go.
Again it's just a matter of trying to stay consistent
as you're working on the particular model.
Keep track of how many vertices that you're creating
as you're creating them.
As you can see it almost looks like it's basically goggles
which in a way it is.
We're just trying to design polygons that will encapsulate certain areas
and certain parts of the model.
I'm going to add in another point here, Ctrl.
Every time you're going to create something
you have to go into and out of the create tab.
That's why I'm doing that.
I'm going to go ahead and bridge this, there we go.
The interior course you would actually grab these edges in another program.
I can't extrude these edges for this to be able to pull it in.
This is a surface program, so I can't technically pull polygons in to extrude it
but again, if you know anything about modelling
you'll know you need to extrude this stuff inwards a little bit.
Then you can create a sphere for the eyes.
Let's go in, I'm just going to add in a couple polygons here.
Pull my Ctrl key, again Ctrl and Ctrl that snaps it.
It's going to just fill that in
and grab this here and again hit the zero symmetry.
All right, so right off the bat, we go ahead and grab our vertices here.
I can now create symmetry, there we go.
If I turn off our reference,
see there you go, right off the bat.
That's modelling for animation purposes because this is completely animatable.
If this was textured and that mouth starts to extend and move around
and the lips move,
these polygons will move with it.
It will now move with the flow of the geometry
rather than just geometry for the sake of it .
Of course, you can then build out from here.
Build the nose and connect all these pieces
because again, within the cheeks
you might not need to do a whole lot of the edge looping.
Now you might want to carry out some of that edge looping
maybe for a little bit more,
if you think it's going to be a really animatable face.
I would turn around and just extend,
if it were me I'd just extend some of this around as much as possible.
Following in the basic flow
and this is just left-clicking and dragging
or left-clicking on the model and that's it, that's all I'm doing.
As you can see too, as I spread out away from the areas,
away from the rubber bands, I can actually make my polygons bigger and bigger
because they don't need as much deformation as up in the mouth area.
That's one of those things that you want to kind of pay attention to.
Let me turn off the reference again.
You can see by the mouth and everything
the polygons are smaller
because it's going to be more concentrated detail in that.
By the time I get to the edge of the chin, it's not so much.
You can actually vary that, etcetera.
With the arm let me show you really quickly what I would do.
I keep this basic, again this is not like it's a bad model
or a bad thing when you're modelling something
but what I would suggest you do is,
and you can do this in Topogun as you're building.
You can double click one edge and it gives you the whole edge around.
Just hit connect, okay just gave me that extra edge loop.
Let's go for this connect.
Now we got a extra edge loops around our shoulders which is good.
Let's go ahead and create an extra edge loop around the elbows
or where the elbows are.
For this, let's go ahead and start taking out some of this.
We don't need all of these edge loops here.
Going to go ahead and collapse that.
Maybe going to go ahead and collapse this one.
I'm going to collapse this edge.
As you can see, there is a difference between this side,
this side here and this side there.
This side works better for animation.
At the joint we've got more edge loops,
at the joint we have more edge loops, in between not so many.
You'll notice that with all these edge loops,
this shape looks no different than this shape.
If it's about a silhouette which it is in video games
you're not going to notice that this only has this few edge loops
as opposed to the fact this had like two or three times more.
All right, so anyway I hope this has been helpful.
Keep in mind again, the areas that are going to be animatable
you want to try and keep in mind to think of rubber bands.
Make sure there's a number of different edge loops in there
and less in between those rubber bands.
You should get a really good model out of that.
I hope this has been helpful.
My name is Stephen G. Wells and this has been 3dmotive.com.
Thanks for watching!