UnWrap UVW help.

[markf]

I am having trouble understanding how to use the Unwrap UVW properly. Attached is a screen shot. First I modeled the sofa. The sides bottom and back are all one object - Base. The pillows, cushions, legs and piping are separate objects. I'm trying to use Unwrap UVW on the Base.

 

First I apply the modifier click the edit uv button and in the Edit UVW's dialog I select pack UV's. That puis all of the parts into the small blue square. The scale of the texture is way too big so I select everything and scale it all up untill it looks correct. This seems rather arbitrary and random with no ability to see a scale amount value etc. Now all of the various separated groups of faces are outside of the smal blue square. Does that matter?

 

The area that I have selected on the arm of the Base is an area that is not mapped properly. If I click the cylindrical button in the map parameters roll out, the selected faces rotate in the dialog oddly and get very small and repositioned and it doesn't look correct. Texture scale is now too big in that area and texture is rotated oddly. I see a cylindrical mapp gizmo in the viewport but I can't find any controls to adjust it's size etc.

 

I have done a number of tutorials and tried to learn the Unwrap UVW but it eluding me. I realize this is complex and I'm not sure if anyone can help me with this, but I thought I'd give it a try here. I've had very good results with critical help form you all in the past.

 

TIA for any help!

[Billabong]

you need to make sure your uvs are inside the square space and are taking up as much 0-1 uv space as you can.

 

Im not sure if you done this tutorial, but it should help you. Its a little old, but still a very good one

 

http://www.game-artist.net/forums/spotlight-articles/2329-tutorial-3ds-max-unwrapping-techniques.html#post21497

[markf]

Thanks for your reply. I'll check out the tutorial. I am wondering if I do need to get all of the uv's inside the small blue square. Because I had to scale them all up to make the texture appear the right size they no longer fit in the small square at all. I'm confused as to how they could fit now that they are so large in comparison to the blue square.

 

I was thinking that perhaps it doesn't matter if the uv's fit inside the square if one is not planning on rendering the square and getting it into pshop to paint thier own texture. (hope that makes sense).

[William Alexander]

You will benefit greatly from viewing some UV tutorials. UVs are really pretty simple once you get the hang of it but not so easy to explain at times ;P

 

 

...and yes they should fit in the blue box. Anything outside the blue box is in the UV 'Repeat' territory. So if a UV poly over laps the edge of the blue box on the left it basically starts to 'repeat' from the right hand side of you raster image you are mapping to. SO where the blue line intersects that UV poly you will show the repeat of the mapped image on your model's polygon associated with the mapped UV poly...all things being mapped 1to1 in the repeat parameters.

 

...and so it goes with talking UVs in my world

 

Cheers

[markf]

Hi and thanks for your reply! I believe I understand what your saying. In my case I'm using a tileable (seamless) texture, so, am I correct in saying that in this case it doesn't matter if the uv's fit inside the blue square?

[Billabong]

As William said, Its just good practice to keep them in the box.

 

Here is a little tip for you.

 

When you start to unwrap, uncheck normalize map in the command panel of the UVW Unwrap. that way when you unwrap each piece, it will give it the correct scale of the object and not try to fit in the box, once you have everything unwrapped, then scale everything down together globally, and then start fitting them into the box.

 

As far as your question is concerned, i really cant answer that, because I have always stayed in the box

 

-B

[markf]

Yeah, I'm out of the box . But really I would like to have those uv's in the box if that's what's correct and/or needed. The problem is that when they are sized small enough to all fit together in the box (like if I choose "pack uvw's" to fit them all into the box) the scale of the texture on the object is much too large. Is there some way to accomodate the texture scale but still have all of the separate uv's fit in the box?

 

Clearly I am not doing something correctly. I'm trying to figure out what.

 

Thank you for your help!

[luckymutt]

The blue box is just a 1 to 1 representation of your texture. Get 'em all in the box and if its too small, then zoom in

With all the UVs packed, if it looks like poo-poo in the viewport, then either it is just a viewport display issue or your texture itself is too small.

What is the size of the texture itself?

[markf]

Hi and thank you for your reply. I'm not sure I understand. If I get them all in the box I can see them just fine, that's not my touble. It's that the texture is then too large on the geometry. The texture map is 1200 x 1200 and represents about a 12" x 12" section of fabric.

 

Also if the box is a 1 to 1 representation of the texture, I am confused as to why the texture displayed in the Edit UVW dialog extends well beyond the box ( see the attached screen grab above) ?

[Billabong]

why not just render out your uv template and apply the textures in PS, I know you said that you didn't want to do that, but honestly if you not going that direction, I really don't see the point of unwrapping

 

-B

[markf]

That's a good question. I was under the impression that the UVW unwrap worked that way but that it was also used in the way I am attempting. I manipulate the various UVW's by rotating or scaling or whatever in the Edit dialog and don't need to go into pshop to create a new map on top of the exported UVW patterns. The tutorials I have done seemed to work that way. The tutorials did explain how one could export the patterns within the blue square and then apply textures to a layer(s) to match in pshop, but my impression was that was not always needed. Especially if using a seamless map like I am using.

 

I may be getting a better understanding of this, thanks to all of your help. There are still features of the Unwrap that I don't understand. I am probably over thinking some of this ( common for me). I have also found that tutorials are a good start but the only way to really get it is to use it in a real world project of one's own.

 

I have a couple of tutorials from the 3DATS books and searched the Area and some other sources for Unwrap tutorials. I made an effort to find and view what I could but it's still not clear to me how to really control the Unwrap. I'll keep trying and ................

 

Thanks again.

[Billabong]

you should really watch that tutorial I posted a link to, it gives a really good example of unwrapping

[markf]

Your right about that tutorial. I have watched more than several and that one is the best. Thanks for the link! I'm still left with some questions and confusion but definately helpful.

 

The other big help was the tip above about unchecking the normalize map box during flatten and also during subsequent mapping of clusters. This seems to me especially helpful when using a tileable /seamless map. It seems to be the only way to ensure that the texture is applied at the same scale to all of the clusters. I also find that if a tlieable map is being used and the clusters are not to be exported to pshop for creating a custom map, it is not necessary to fit them all into the box. Get the mapping the way you like and uniform scale all of the clusters together to achieve the desired texture scale, don't worry about the box.

 

I get the concept that Unwrap UVW is like splitting an object into a bunch of sub-obgject selections each with it's own UVW map. It's understanding when, where and how to make it work that's making me feel a bit drain bamaged. I think I have this mapped correctly now

 

I am trying to develop my furniture modeling and texturing skills. Attached is the simple sofa base I have been working with. My question - is Unwrap a good strategy for texturing such an object? The difficult area was where the sides transition into the tapered cylindrical shape. The rest could be done with one UVW box modifier.

 

Thanks for all of your help!

Edited October 26, 2009 by markf