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Leonardo Vega
08-03-2005, 04:56 AM
When Uvmapping a character, should you do it after he's subdivided or can you just map the low-poly version and later just subdivide it?

Any good reference material for learning BodyPaint but specifically on uvmapping. I'm kinda just winging it now. It seems like for the head, cylinder projection is best, true?

Any news on normal mapping?

- Leo

Erik Heyninck
08-03-2005, 06:59 AM
There is a good tutorial somewhere over at renderosity but it's not in the tutorials section. Best wait for Anders (Cartesius) over here, or ask over there.

The principle is to limit to selections and do separate unwrappings.
The wizard is not always the best road to follow.

Keith Young
08-03-2005, 08:00 AM
I find it much easier to do the mapping on the low-poly version. Then be sure to set your HyperNURBS object 'Subdivide UVs' option to 'Edge' for best results (you can think of this as doing the same type of subdivision that it does on your mesh... it will do the interpolation along more of a spline curve rather than just splitting the difference when creating the new UV coordinates for the smoothed mesh points).

As for methods, I don't recall seeing the tutorial that Erik mentions, but you can achieve a type of bear-skin unwrapping by doing 'frontal' mapping of sections of polygons from different views (front, side, etc) and then stitching them together... unfortunately, BodyPaint doesn't seem to have a UV-stitching feature, but I've got some plugins under development to solve that ;) (this thread (http://www.renderosity.com/messages.ez?ForumID=12400&Form.ShowMessage=2316384) show a bit on the plugins.. just skip down to post #21.. the head shown in that thread was mapped as I describe above).

But barring the above method, yes, a cylinder projection is probbly the next best thing (not great) for the head.


- Keith
Red-i Productions

JamesMK
08-03-2005, 09:56 AM
Most of the time you'll get the best results by using flat projections on carefully selected sections of the mesh, and then you stitch these parts together as far as possible to get large continuous UV-islands.

And most of the time you will find that the automatic unwrap made by the wizard is never as good as a hand-tweaked map made using the above method.

Aaaaaaand most of the time you will, as pointed out by others, find that working on the low-res cage, non-subdivided mesh, is a good way to go. This however requires that the cage is somewhat sane, i.e. doesn't deviate too much from the smoothed result. If you build good meshes, this comes automatically.



.

Cartesius
08-03-2005, 10:24 AM
The tutorial Erik is talking about can be found here:

http://www.renderosity.com/messages.ez?Form.ShowMessage=2004888

It's very quick and dirty as I wrote it on the fly some time ago but it should explain some basics like Interactive Mapping and how to work with selection tags.

About your questions: I agree with the rest that you should always UV-map your low-res mesh. Like Keith says you should set the HN to Edge (or Boundary) to avoid stretching and pinching. For heads I tend to use either Cylindrical or Spherical mapping (using Interactive Mapping) but like James says, many features can be mapped using Flat mapping. I tend to map ears that way, for example.

A final tip is to assign a checkered pattern to the mesh so you can clearly see where you need to say relax or tighten UV's.

So far BP-tuts are pretty rare but I know 3DKiwi is working on a set of tutorials to be released on CD or DVD pretty soon. There's also the DVD by Vital Distraction that I have ordered but not yet received. I know there are some other commercialy available training sets available as well but I can't remember them right now.

I really should post a link to that mini-tutorial at Renderosity in the tutorials section...

/Anders

PS. NEVER use the Wizard! DS.

Leonardo Vega
08-03-2005, 01:08 PM
Thanks guys! Awesome tips! :D Now when using frontal maps, I should always rotate my view until the selection is facing the front right? Or am I limited to using the front, back, bottom, sides, etc. views?

So mapping a checkered pattern will show me where it stretches (like when I see a white or black box stretched) and they I can relax it? I'm not sure how to "relax" the uvmap or what stitching means.

Btw, don't worry I don't like wizards, usually automated stuff is never GREAT, just descent. Is interactive mapping the way to go? I usually just select my polys and pick the mapping style.

I'll check out the tutorials as soon as I sign on Renderosity! :)

(Edit: I just read the tutorials, nice job guys! From what I see, I need a plugin to stich broken mesh. But I'm still confused on relax feature. The tutorial makes it seem that the relax function is used to spread out the mesh more, eliminating some overlapping. So if I see a part that is too stretched do I just select those polys and relax them or will relax affect my whole selection?)

- Leo

Leonardo Vega
08-03-2005, 01:48 PM
I noticed some game models use alpha maps to create cool hair (like the rat on the front page). Is that as simple as just making another image and filling it white and painting black what you want transparent then using it in the alpha section of your material?

- Leo

umblefugly
08-03-2005, 03:09 PM
So when do you think your plugins will be available Keith?

Cartesius
08-03-2005, 05:14 PM
I noticed some game models use alpha maps to create cool hair (like the rat on the front page). Is that as simple as just making another image and filling it white and painting black what you want transparent then using it in the alpha section of your material?

http://www.cartesiuscreations.com/wips/hair.jpg

Yes, that's exactly how it's done - you paint your hair alpha and load it in the Alpha channel, load a hair colour map (or procedural shader) in the Colour channel and hit render. That's what I've done above (the alpha map is very preliminary in this render). The hair is modeled with lofted splines, basically three splines to form a "sheet" of hair that is then textured.

/Anders

Keith Young
08-03-2005, 05:47 PM
So when do you think your plugins will be available Keith?

Hey UF... the plugins are 'functional' right now - they do what *I* expect them to do, but I hadn't yet put a lot of thought into what others might think/expect/assume they do ;). I also want to add a few options (tolerance settings, etc).

At the moment, I'm trying to get an eMac set up to do the Riptide port, so it may be a while before I get back to these other plugins (although I might also try compiling those on the Mac as a test-case).

umblefugly
08-03-2005, 06:08 PM
Cool Beans,keep us updated bro:thumbsup:

Leonardo Vega
08-03-2005, 07:01 PM
Very helpful are you, yes indeed.

Quickie: When you saw assign a checker pattern, do you mean just get the 1024x1024 map and instead of coloring, make the whole thing a checker pattern?

Will BP make an auto checker pattern for use lazies? :)

- Leo

Cartesius
08-03-2005, 08:42 PM
Quickie: When you saw assign a checker pattern, do you mean just get the 1024x1024 map and instead of coloring, make the whole thing a checker pattern?

There are several ways to accomplish a checkered pattern. I use a 1024x1024 bitmap with white and red squares while some use the same size but different coloured squares (red, yellow, green, purple, blue, etc). Still others prefer to have numbers on each coloured square, going from say 1-60 or 1-120 depending on how many squares make up a single row. You can also skip the bitmap altogether and go the procedural route by creating a checkerboard pattern and scale the U and V frequency to taste.

When you have the map ready, load it in the Luminance channel and apply it to your mesh using UVW Mapping. You'll see immediately where the texture stretches, pinches or distorts. Here's where BP and Interactive Mapping comes in, follow the procedure outlined in the mini-tut at Renderosity and you'll soon get the hang of it. :)

Check out Unwrap3D (http://www.unwrap3d.com/index.aspx) for some tips on using a checkered map to sort out distortion.

/Anders

Leonardo Vega
08-03-2005, 08:43 PM
There is frontal mapping and flat mapping, when you guys said "flat" did you mean flat? :)

Because I get louzy results...

- Leo

JamesMK
08-03-2005, 08:47 PM
Usually 'frontal' - that is, select the uv polygons you want to map, adjust the camera to an optimal view, then make a frontal projection... after that, scale/rotate/move the UVs as needed.

3DKiwi
08-04-2005, 05:53 AM
Re chequer board patterns. i find an easy way is to create a new layer and hide all of the rest. Your model then displays the pattern and it's easy to see where you have distortion. Another test is highlighting the uv's with a thin brush. This shows up any bleeding where your polygons don't have enough pixels.

My BP CD's are 3-4 weeks away roughly. Almost finished recording the final video section.

$49.99 US plus p&p

3DKiwi

Cartesius
08-04-2005, 07:14 AM
For me Flat is Flat, I rarely use Frontal (except for Projection Painting).

/Anders

Leonardo Vega
08-04-2005, 02:50 PM
kiwi: Thanks! Can't wait to see your videos!

cart: hmmm... I will have to do some more playing

Quick question, I was trying to texture a model that was made of seperate peices, but couldn't do it. Does he require seperate textures maps? Or can I texture the whole thing with one 1024x1024 texture map? If so, how?

- Leo

Cartesius
08-04-2005, 05:06 PM
Flat mapping is the most common mapping type when using Interactive Mapping, that's why it defaults to that type when starting the tool.

Quick question, I was trying to texture a model that was made of seperate peices, but couldn't do it. Does he require seperate textures maps? Or can I texture the whole thing with one 1024x1024 texture map? If so, how?

Yes, you can - apply the material to your first piece and unwrap/UV-edit it. When satisfied outline the polygons on a separate layer (check either the FAQ on the Renderosity Cinema 4D forum or Maxon's tutorials, it's described how to do it there). Switch to your second piece and apply the same material. In the UV-edit window you will be able to see the outlines of your first piece and that way you know which space on the canvas that piece occupies. Unwrap/UV-edit your second piece and make sure it's UV's occupy free space on the canvas. If needed outline the polygons again and move on to the next piece.

/Anders

Rabbitroo
08-04-2005, 06:04 PM
My BP CD's are 3-4 weeks away roughly. Almost finished recording the final video section.

$49.99 US plus p&p


Can you tell us more about your CD's--is there a thread discussion them? Who's the target audience (e.g. beginner-intermediate-advanced)?

Thanks!
-K

Keith Young
08-04-2005, 09:59 PM
I just posted this tutorial (http://www.renderosity.com/messages.ez?ForumID=12356&Form.ShowMessage=2364036) - might be useful, might not ;).

Cheers,

- Keith

doohicky
08-04-2005, 10:15 PM
Great tut Keith...thankyou...I'm looking forward to the plugin!

D

Leonardo Vega
08-04-2005, 10:52 PM
Thanks for the tutorial! I can't wait for your plugins!

- Leo

Keith Young
08-04-2005, 11:39 PM
Flat mapping is the most common mapping type when using Interactive Mapping, that's why it defaults to that type when starting the tool...

/Anders

You know, I hadn't played with the interactive mode yet.. I'll have to give that a try, but (at least when not in interactive mode), flat mode seems to work more like a cubic or box mode.. it doesn't map from the direction of the camera (which frontal does). Frontal mode is also dependent on the zoom (or distance?) of the camera, so you can adjust scaling to some extent while you're at it.

- Keith

3DKiwi
08-05-2005, 07:59 AM
Re CD's - target audience is beginners / those struggling with BP with particular focus on UV editing and UV tools.

The final project is UV mapping and texturing a Spitfire. Total length around 11-12 hours. All UV tools are demonstrated.

Thanks for the interest.

3DKiwi

Cartesius
08-05-2005, 09:27 AM
flat mode seems to work more like a cubic or box mode.. it doesn't map from the direction of the camera (which frontal does). Frontal mode is also dependent on the zoom (or distance?) of the camera, so you can adjust scaling to some extent while you're at it.

That's right, Flat mapping is flat regardless of the camera and that's why I like it :) You just rotate the Texture Axis as you do in regular C4D and you can still use the camera to rotate around the mesh to check for correct angles. You'll get a live preview of your UV's in the UV editor viewport while rotating, scaling and moving the mapping type.

I read your tutorial at Renderosity (very informative, by the way, should be a big help for many new to the process!) and I can understand why you use Frontal as it will automatically assume the direction of your camera. My use of Spherical of Cylindrical mapping is basically just a different way to reach the same goal - I usually don't have to stitch any UV's but the relaxing still applies.

/Anders

Keith Young
08-05-2005, 10:07 AM
That's right, Flat mapping is flat regardless of the camera and that's why I like it :) You just rotate the Texture Axis as you do in regular C4D and you can still use the camera to rotate around the mesh to check for correct angles. You'll get a live preview of your UV's in the UV editor viewport while rotating, scaling and moving the mapping type.

I read your tutorial at Renderosity (very informative, by the way, should be a big help for many new to the process!) and I can understand why you use Frontal as it will automatically assume the direction of your camera. My use of Spherical of Cylindrical mapping is basically just a different way to reach the same goal - I usually don't have to stitch any UV's but the relaxing still applies.

/Anders

Cool, I'm always interested in new methods. As I mentioned over there, I already had/have some plans to play with Cylindrical/Spherical mappings more too. I'd be interested to hear how you get by without doing any stitching...

Thanks for the comments.

- Keith

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