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IMI
10-22-2008, 06:38 PM
UV space. Is there a way to make LW utilize the UV space beyond and below 0-1?

If that's not clear enough, that UV grid you get in Modeler is a 0 to +1 grid, where it goes from 0 to +1 on the U and the V.
But there are many other possibilities, such as negative vales, if I'm understanding it right.
I was watching a Maya video where the guy used UV's outside of 0-1, and was able to do so by typing in values for the texture locations, based on where in UV space the relevant UV's were for the parts outside of 0-1.
The advantage to this, for one, is a way to achieve high resolution image mapping without a whole lot of different UV maps for a complex object; the more of the grid the UV map can fill, the higher resolution you can get.

Is there a way to do this in LW?
Thanks. :)

MooseDog
10-22-2008, 06:41 PM
you can move points outside the "grid" very easily. what'll happen though is that the image will just repeat it's 0-1 limits.

hrgiger
10-22-2008, 06:49 PM
Yes, I often move my UV's outside of the 0-1 range when I want to scale up or down my texture in relation to the object, sometimes there is not enough room to do it in the UV space(Providing I'm using a seamless texture map). It won't help you in the way that you're talking about if I'm understanding you correctly.

IMI
10-22-2008, 06:51 PM
you can move points outside the "grid" very easily. what'll happen though is that the image will just repeat it's 0-1 limits.

Yes, I know that, that's the problem.
So, LW is in fact limited to only 0-1? No way around that?
I'm kind of sketchy on details, as it was a while ago, but the video I saw also used ZBrush, and the UV's outside were also somehow forced, in ZB, to correctly render displacement and normal maps as well, and then again, in maya, the outside UV's were used in conjunction with the normal UV's, by inputing values.
No way to do it with nodes, maybe?

Of course, the obvious workaround is just make a new UV map for each part needing alot of texture detail. But who decided we should only be limited to 0-1, anyway? ;)

IMI
10-22-2008, 06:53 PM
Yes, I often move my UV's outside of the 0-1 range when I want to scale up or down my texture in relation to the object, sometimes there is not enough room to do it in the UV space(Providing I'm using a seamless texture map). It won't help you in the way that you're talking about if I'm understanding you correctly.

Thanks.
Yeah, I think you understood what I was asking. At least, I understand what you're saying. ;)

hrgiger
10-22-2008, 07:53 PM
I guess I'm not understanding how anything else would work. It still has to coordinate with an image, but you can use any resolution of image you want currently in Lightwave, why would say using a negative input help you? You can use a large image and scale down your UV's to fit anywhere on them with what we have now. Do you have any videos or links towards how this works in Maya?

BTW, I broke down and got UVLayout (uvlayout.com) with some money I had after selling my PS3 (never played it anyway). I hope to have some time to play with it soon but I just thought it looked too good.

IMI
10-22-2008, 08:27 PM
I guess I'm not understanding how anything else would work. It still has to coordinate with an image, but you can use any resolution of image you want currently in Lightwave, why would say using a negative input help you? You can use a large image and scale down your UV's to fit anywhere on them with what we have now. Do you have any videos or links towards how this works in Maya?

BTW, I broke down and got UVLayout (uvlayout.com) with some money I had after selling my PS3 (never played it anyway). I hope to have some time to play with it soon but I just thought it looked too good.

I don't know - it's hard to describe what I'm thinking, and I won't discount the possibility I misunderstood what I was seeing.
Picture this - you know what the 0-1 space looks like in LW. The screenshot here is from modo, showing the parts of the UV we don't see in Modeler. I don't have Maya, so I can't show that.

Now, we know that if we make a UV map in the upper right quadrant - the 0-1, in Modeler, we can take that UV map into Photoshop or any other painting program, and paint over it, then apply that image to a model with the appropriate UV map selected, and we'll see the texture pinned to the vertices of the model, according to the UV map.

What I'm saying is, what if we could drag UV's beyond (or below - to negative values) 0-1, and paint over the whole range instead of just 0-1, and have a way to tell the program to consider all of it instead of just 0-1. The result would be we could get more detail into a single map, rather than having to optimize the available UV space real estate for our parts/surfaces within that limited range.

Thinking about it now though, I don't know though how realistic it would be to need something like that. Fortunately, LW treats UV's as layers, so you can have as many UV maps occupying that 0-1 space as you have surfaces. You could even make a separate UV map for each polygon, if you wanted to.

I can't remember where I saw the video. Somewhere... "out there" on the www, and it's been intriguing me ever since. I should have bookmarked or downloaded it, I suppose. Maybe some maya guy will come along and offer some insight. Where's Jin when you need him? ;)

Please, by all means, let us know what you think of UV Layout after you've had a chance to get familiar with it. I've been considering it, because it looks far more advanced than what I've been using - modo 302.

geothefaust
10-23-2008, 12:07 AM
I've seen a couple Maya videos with UVs be edited and parts being placed into the UV space outside of 0-1. But, they have always put all geometry they want used >back< into 0-1.

No program I'm aware of is capable of using the space outside of 0-1 for UVs. Because the image you provide for the UV map will *always* only occupy that space, nothing more or less. I'm really not sure why you would want to do so anyway.

If you need to fit more geometry, the only solution is to scale everything down into 0-1 space for the UV map. If you need more detail, of course you can always just use a higher res image.

IMI
10-23-2008, 04:23 AM
Yeah, I see it all now. I'm not real sure what I was thinking, just grasping at straws hoping to be able to use more UV space without making more maps.
Thanks for all the info. :)

Lightwolf
10-23-2008, 04:43 AM
I've seen a couple Maya videos with UVs be edited and parts being placed into the UV space outside of 0-1. But, they have always put all geometry they want used >back< into 0-1.

Actually, values beyond the 0..1 range are used, how depends on the wrapping mode being used, so they are wrpped back into the 0..1 space for the actual rendering process.

I suppose you could use values outside of 0..1 and shift those in using the offsets that some of the projection/mapping nodes provide.

I am suspecting that this technique really only makes sense for apps that are limited to one UV in the first place.

Cheers,
Mike

hrgiger
10-23-2008, 08:13 AM
I've been playing around with UVlayout some this morning and find it utterly delightful after working with Lightwave's UV tools for so long. I just went through a quick start tutorial so I would say I'm hardly familiar with all the tools but I took this hand model I had and unwrapped it in a couple minutes. I haven't gotten to the parts yet about welding pieces back together yet.
What's great about this is it gives you a visual color reference on where your UV's are being distorted. Green is undistorted, reds are texture stretching and blue is texture pinching. It has all the usual UV stuff, pinning, relaxing, smoothing and you can manually adjust vertices, and it constantly gives you the color feedback.
Here are the UV's I laid out for a high rez hand model and it literally took me less then a few minutes to do and it's fun watching it unwrap. I meant to post the view of the hand with the checkered texture on it but I accidentally closed it before I could screen grab it but it looked pretty flawless (other then the seams from the different islands or shells. EDIT: By the way, you'll see reds and blues but they're slight. The darker the red or blue, the worse the distortion is. You really only have to worry if it gets too dark but on the model, you hardly see the distortion from the slight blues or reds you see in this UV.

IMI
10-23-2008, 10:13 AM
That looks good, HR, sounds like a cool program. Obviously I've heard of it before, just never tried it. I think I might look into it now.

hrgiger
10-23-2008, 10:40 AM
Yeah, it's very cool. Here are the basic videos where you can really see it in action from someone who actually knows how to use it http://www.uvlayout.com/index.php?option=com_wrapper&Itemid=97

IMI
10-23-2008, 04:43 PM
Thanks. I do believe I'm interested in this. Not so sure though the old lady's gonna let me buy it, unfortunately. I guess it's butt-kissing time. ;)

Lightwolf
10-23-2008, 04:47 PM
Not so sure though the old lady's gonna let me buy it, unfortunately. I guess it's butt-kissing time. ;)
Could you please leave the details for yourself the next time? Now I've got disturbing images in my mind that will haunt me... :D

Remember, most of us are graphically oriented ;)

Cheers,
Mike