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Fuu
10-03-2005, 09:54 PM
Ive been trying to UV map a hilt that I made in gmax. However, I find that I am having difficulty. I have come up with this:UV Map (http://img398.imageshack.us/my.php?image=untitled24qa.jpg)

I made it using the "Waylin Uv Tut" but at this point I am confused on how you move the diffrent "faces" so that they dont overlap. I understand you have to scale them down in proportion, but how do you go about selecting only a single "face" ( I want to say "face" here but im not sure if this is the correct term... I'm considering a "face" to mean a group of polys that make up a "side" of the model) and move it so ther isint overlapping <in gmax/nwnmax>? Many of the tooltips in the "Waylin Tut" are only in the 3dsMax version, so I'm somewhat bewildered.

Because of this roadblock I decided to forget the "Waylin Tut" and start over using just Svosh's tut. So, I've started "detaching" some of the faces but.......... Am I one the right track? I've detached some "parts" already, starting from the top face and moving down. Each selection consists of multiple faces like this, (http://img311.imageshack.us/my.php?image=untitled14ke.jpg) and this (http://img396.imageshack.us/my.php?image=select21gb.jpg)

Is it okay to have many selections <in the second pic, bottom left> included in each "detach" command?

Thank you in advance.

Fuu

Det. Bart Lasiter
10-03-2005, 11:36 PM
When you go into the 'Edit UVW's' window, click Mapping->Flatten Mapping. From there you can tinker with the 'Face Angle Threshold' and 'Spacing' values to get the pieces the right size. Try setting the threshold to 90 though, it usually makes it have less pieces.

cchargin
10-03-2005, 11:36 PM
Hello,

Ahh yes, uv mapping. I have always felt that uv mapping in gmax is much harder than it should be.

I try to make things easier for myself by using the material IDs.

When you are editing your mesh you can select groups of polygons and assign them a material ID. Then in the uvw mapper you can hide uv coordinates by material ID.

Here is how I do it:
- Select your mesh and then click on the "modify" tab
- Click on "editable mesh", then click on the + to the left of it
- You should see a "Face" entry under the editable mesh, click on it
- Now select ALL the polygons in your mesh
- In the rollout section look for "Surface Properties". You will see a group "Material". Type in a really big number. This sets ALL you polygons to this material ID
- Now start selecting groups of polygons that you want to uv map seperately from the rest of the mesh and assign them material IDs starting from 1.
- When you assign a group of polygons a material ID you can click on "hide" at the top of the rollout to hide those polygons. This will make it easier to select your next group of polygons.

Once you have assigned material IDs to all the polys then you can unwrap the UVW and you will see a drop down that has "ALL IDs" in it. Click on the dropdown button and you will see all of your material IDs listed. Select one ID and you will see ONLY the polygons for that ID!

Note: Usually how you group material IDs is the same as how you would chop up the mesh as Svosh described.

Fuu
10-03-2005, 11:48 PM
Oops, I edited my post before seeing the new ones....
Thanks guys! Its nice to get tips from the masters! I'll go try this stuff out, will be back if I have more questions.

Thanks again.

Fuu

svösh
10-03-2005, 11:58 PM
@jmac7142 Unfortunately Flatten Mapping is only in MAX as well as many excellent
features that make mapping a breeze, like sync to viewport , select polys, ignore
backfacing and more.


I always detach after it’s modeled so don’t have to keep going down my
stack It makes work folw go a lot smoother and you could possibly corrupt
your uvw unwrapping if you repeatedly go down the modifier stack.


@Fuu Yes when you detach you have to check on to element, our hilts can only be one solid mesh.

your uv map looks good to me as a start, now in the second image you have
showing if that is detached as an element , click any empty place in the viewport
to deselect the ploy’s then you go to the unwrap uv

Go to the sub level of unwrap uv and click select face

Reselect those same polys in select face subs ;)

Often for saber models is easiest to select polys in the front or left view ports
and if mirroring doesn’t bother you, you can unwrap more then ¾ of your hilt
on Y = left to right or X = front to back and the rest on Z = top down

With that selection you have in the second image if mirroring the image is ok with
you then in the Sub object Perams: you would choose the Y or X axis in the
front / back or left / right view ports.

In perspective viewport you will see the mapping gizmo is yellow and will be in
the center of the hilt bisecting those polys fromm left to right, or front to back.


If you were to map that on Z your skin will use 1 pixel of color for that section
and the flattened map will look like a circle and not what you want.


Play with these 4 options to find the best way your skin will look on your model.
You see the difference the 4 mapping axis’s give you, hit planar to see your
mapping in the edit window if it is not what you wanted just hit ctrl + Z to undo

I normally reserve the averaged normals option for odd angles or organic shapes.

An example of this on a hilt I made is kavar’s shield from the USM the very
top if the emitter was mapped using averaged normals.


when your are satisfied with the way the gizmo is appearing on your model then you
hit planar map button in the edit window your shape will appear on top all verts red.
Now move it over right click your shape and a small quad menu appears all of the
tools above can be accessed here as well move, scale, rotate,

so move the element out of the actual square area with enough elbow room for the
other parts. And repeat until all elements are mapped on either Y, X, z or
averaged normals . in the edit window once you have all your parts out the square.
You can arrange them in the best way to make your skinning job go smoothly.

Area select them all and scale them down , now start moving them in to the square
area With about 5 to 10 pixels between them for ease of skinning, try to keep them
uniform in size and the ones that take a lot of detail you can scale up a bit.

Now to skin see my thread for getting the uv map for skinning ;)

For your next one I suggest using a 8, 10, or 12, sided Ngon. your count on your
hilt is going to be very big in that top selection alone in pic 2 it shows 56 faces
that’s 28 polys aound

We use smoothing groups to fake smooth edges so the models are lower poly but still
look like cylinders, depending on the design of the model.

EDIT: In ; image=select21gb.jpg
select all extruded grip sections and detach them together.

Then when mapping select each one individually map on average normals make sure you
don’t miss selecting a poly move it off the to side do this for each one , now stack
them on top of each other in the edit window to save room on the uv it will also
making skinning them go faster. Now select each vert example the far top left area
select it, make sure all of the verts are selected on allof them and go to scale and
scale them until it looks like one single vert. Repeat this for all the other 7 groups
of verts. You can tweak the shape if it gets skewed,
by selecting the verts and moving them a bit. However if you want them to each be unique
don’t stack them.

I hope this helps

svösh

cchargin
10-04-2005, 02:19 AM
Hello all,

A few notes on Kotor+gmax+MDLOps...

our hilts can only be one solid mesh.
A hilt has to be 1 object, but you don't have to weld all of the vertices. This will let you get around some of the Kotor uv mapping oddities. Remember that in Kotor you can only have 1 uv coordinate per vertex!

We use smoothing groups to fake smooth edges so the models are lower poly but still
Ok, here is how "smoothing" is done by MDLOps. Basically if 2 faces are welded together they will smooth! So, if you don't want smoothing then break the verticies. The smooth groups in gmax do NOT translate to MDLOps or Kotor!

So here is the aggravating part of Kotor modelling: For easier uvmapping you have to break the mesh into pieces, for smoothing you have to weld them together! Argh!

LSaberDuelist
10-04-2005, 12:01 PM
It is also helpful to look at UV-Maps created by other modders to learn a few tricks. To do so, choose a lightsaber from USM(they all have very efficient maps), convert to mdl-ascii with mdlops, import in gmax, select the hilt, add an unwarp uv modifier on top of the modifier stack, then you have a look at the lightsabers map. I learned alot from looking at these maps.

oldflash
10-07-2005, 08:37 PM
I do mapping in that way: http://img63.imageshack.us/my.php?image=clipboard032jm.jpg (http://img63.imageshack.us/my.php?image=294vg.jpg)

Just to be sure I was detached polys that need to be detached and is easy to select on uvwunwrap process.