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ArneK
07-26-2003, 02:05 AM
I'm currently in the process of texturing a hi-res subdivision model of a female, and I'm getting mighty frustrated. Due to the fact that Lightwave is causing a lot of stretching to the UV's when it really shouldn't. Is it supposed to be like this or is it a bug? (I'm on Mac OSX)

Now I'm forced to split up my textures a lot more using planar and cylindrical mapping, as this seems to cause less stretching than UV's.

Any tips, tricks or workarounds? I really hope this will be fixed in LW8.

Triple G
07-26-2003, 02:09 AM
Have you seen Jacky Daniel's Smart Map Tutorial (http://www.jackydaniel.com/pages/Tutorial.htm)?

leigh
07-26-2003, 02:16 AM
Stretching is a perfectly natural and normal occurance in UVs, and just needs to be edited out. All programs (Maya, Max, XSI) cause a certain degree of stretching of UVs (some more than others, depending on the surface being unwrapped) simply because that's just how UVs are. Editing the stretching out is really easy - just do it in your UV viewport.

Unless you are referring to the minor distortion caused by UV mapping sub-ds - in which case, check out the tut that Triple G posted a link to.

chikega
07-26-2003, 02:33 AM
I would also check out "Building Digital Dinosaurs" and/or "Building Digital Humans" by Ken Brilliant.

http://www.charlesriver.com/titles/digitaldinosaurs.html
http://www.charlesriver.com/titles/digihuman.html

Ken goes over UV mapping quite extensively and although the books are non-software specific - the bulk of the models were done in LW. I found it very helpful in addition the above-mentioned tutorials.

Ryder
07-26-2003, 11:28 AM
Originally posted by ArneK
I'm currently in the process of texturing a hi-res subdivision model of a female, and I'm getting mighty frustrated. Due to the fact that Lightwave is causing a lot of stretching to the UV's when it really shouldn't. Is it supposed to be like this or is it a bug? (I'm on Mac OSX)

Now I'm forced to split up my textures a lot more using planar and cylindrical mapping, as this seems to cause less stretching than UV's.

Any tips, tricks or workarounds? I really hope this will be fixed in LW8.

it is not Lightwave,... it is the sub-D´s

E_Moelzer
07-26-2003, 01:37 PM
You know, we used to do great character- texturing in 5.6- days, long before there were UV- maps in LW.
I would do the following: separate those parts of your textures, that have visible stretching in them into another texture and another texture- layer in LW (as planar textures in example) and blend them using alphamaps.
CU
Elmar

ArneK
07-26-2003, 02:15 PM
Thank you for your replies. :)

Triple G - I knew I had seen these tutorials somewhere but couldn't find them. I'll give it a try. Thanks!
Chikega - I'll check out those books. I can never have enough books... lol

Leigh - Yes I know stretching is a common problem in most packages, but as you say some are better than others. People seem to praise the "relax UV" function in Maya which eliminates this to a great extent, but I don't have Maya so I don't know. To make endomorphs to tweak the object parts before making UV's is great. This helps on making the texture placements easier. I tweak and move around the points in the UV maps, and this helps in making a more uniform UV - but the SubD still stretches the UV. On texturing a head I have found cylindrical mapping to be better (see my enclosed picture).

http://www.akdesign.no/ezboard/uv_stretching.jpg

Elmar - Yes, I know about that technique, but if the SubD didn't distort the UV's so much, we wouldn't have to split up the textures in so many parts. A straight line in my texture should still look straight, and not curvy and wavy as they do in the current UV's. But it's probably more difficult to fix than I can imagine...

ILM and other studios have their own custom UV tools. Anyone working with those and can explain in what way they are different/better than those in other packages? Just curious...

E_Moelzer
07-26-2003, 05:04 PM
Arnek, I agree that without the stretching it would be easier.
What really puzzles me about all this, is the fact that LW seems to treat projective textures simillar to UV- maps (even though this is not visible in Modeler OpenGL), or otherwise planar textures (or any other projected texture- type), would not work correctly with Endomorphs, bones or other deformation- types.
The projected textures need to be pinned to the geometry for that too.
So the question that arises is: What is the difference between the way the projected textures are pinned to the geometry and the way the UV- maps are pinned to the geometry?
I would guess that somewhere in there lies the key to fixing the distortion- problems with UV- maps and Subpatch- objects.
CU
Elmar

Joril
07-27-2003, 01:26 AM
Originally posted by E_Moelzer
...What really puzzles me about all this, is the fact that LW seems to treat projective textures simillar to UV- maps (even though this is not visible in Modeler OpenGL), or otherwise planar textures (or any other projected texture- type), would not work correctly with Endomorphs, bones or other deformation- types.
The projected textures need to be pinned to the geometry for that too.
So the question that arises is: What is the difference between the way the projected textures are pinned to the geometry and the way the UV- maps are pinned to the geometry? ...

I the beginning that puzzeled me aswell. Now, I think that's just the OpenGl.

Jonathan
07-27-2003, 02:42 AM
I would definitely texture alot more, but I just HATE uvmapping. It is the one thing about 3D I absolutely can't stand. It's not really artistic but it does require a bit of skill and after I model the last thing I want to do is break it apart.

So here' my wish. I wis that I could simply start a primative, create an initial flat map, and then build my model while UV maps are being projected in the process. That would be wonderful, problem is that I just haven't figured out how ta do it and I'm not a competent enough programmer to pull it off yet.

Oh well, It's good to wish for things.

leigh
07-27-2003, 03:19 AM
Originally posted by E_Moelzer
I would guess that somewhere in there lies the key to fixing the distortion- problems with UV- maps and Subpatch- objects.


UV maps are interpolated between vertices (whereas normal projections are straight projected, no interpolation at all). This is why hi-res models have smoother UV maps, because there is less interpolation - UV maps are only accurate at each point (vert) in the mesh. I would guess that the curving of the sub-d's is what messes this up, because perhaps the interpolation calculation does not compensate for this :shrug:

Labuzz
07-27-2003, 10:15 AM
This problem is becoming a Lightwave specific problem ( A BIG ONE for me)...You havn't this problem in Max ( since max4 if I remenber correctly) and in Maya they have fix this prob in the new 5 ( polysmooth command). For me it's a MUST HAVE IN LW 8(along with multiUV/vrtx, Real ortho projection cam, wireframe and texture in viewport, real selection filter in layout, basic snap tool for pivot point in layout " à la Maya"...)
And this have to deal with Basic workflow .

CLAW
07-27-2003, 11:06 AM
That's, right. It has something to do with interpolation. Well, try to freeze your subpatches before creating the UV maps?:D

lwbob
07-27-2003, 11:28 AM
Originally posted by E_Moelzer What really puzzles me about all this, is the fact that LW seems to treat projective textures simillar to UV- maps (even though this is not visible in Modeler OpenGL), or otherwise planar textures (or any other projected texture- type), would not work correctly with Endomorphs, bones or other deformation- types.

Internally uv mapping has been in LW since around the beginning. There was an error that popped up once in a while about not being able to generate uvs for an object back in the LW3.0 days. They didn't let us edit them until 6 though.

CLAW
07-27-2003, 11:38 AM
internal UV's? You talk about front, cylindrical, planar and spherical now? Well, that's not UV's. UV mapping is a reconstruction of the object in a 2D space, U and V.

ArneK
07-27-2003, 03:57 PM
Labuzz - Well, if other packages have managed to overcome UV stretching in SubD's, let's hope Lightwave will too. :)
This would definately make it less frustrating doing texturing work.

Jonathan
07-27-2003, 04:09 PM
Loganarts did an interesting tutorial using weights and planar maps to create textures and blended the sides to keep it from being stretched. It was the damned-est thing I had ever seen. Of course he was using XSI but still it was incredible. No UV,s just planars and weights and the textures came out focused and unseamed. I have been trying to do it in Lightwave but 7.5 doesn't have texture blending. 7.5c does IIRC but I'm still afraid to upgrade because of the 7.5b nightmare which is fresh in my mind.

ArneK
07-28-2003, 06:50 PM
Discreet released Max 6 today and there are indeed some cool features included also in regards of texturing:

" …Paint Studio: New integrated 3D painting system for the creation of texture and other maps. Includes support for multiple layers, painting on multiple channels and across multiple objects…"

Now let's see what NewTek comes up with in their [8] feature list later today :)

Primus
07-28-2003, 09:59 PM
Lightwave but 7.5 doesn't have texture blending.

Actually Lightwave does support texture blending, using alpha maps or weight maps. I've always used Planar UVs and blended with weight maps for detail work since 7 (well since I started with 7.)

As I recall you have Deep Paint Jonathan? You can use it's projection method to avoid using the messy alpha blending method.... Deep Paint in my experience tends to blur textures so I still use Photoshop...

Jonathan
07-28-2003, 10:12 PM
Yeah, but the projection map is not exacting. Once you come out of projection mode, the texture tend to revert to a point. It helps, but it's not a perfect solution. Also the biggest problem I have with Deep paint 3D is that it requires HUGE maps for doing small areas. If I was texturing just the head I'd still need a 2k x 2k map at least to get finer details where as in photoshop and PSP I can achieve it with an image 1/2 that size. In the end, you still need a decent UV which goes back to what I hate most. Texture weapons does help a bit by allow me to visualize mapping but it requires me to save out the LW object from deep paint 3D which automatically makes triangles which is not always desired. Deep Paint 3D is a big help for me as I visualize better when painting to objects but it has its weaknesses which is in the image filters. Often I find myself filtering my images in photoshop or PSP after the fact.

Deep paint 3D however shines in the area of industrial art and environment. I just did the inside of a house for one of my scenes and it turned out spectacular with only one pass of the brush on each surface laying down bump, spec, color and diffuse all at once.


Yep I just realized you can blend planars using weights and gradients. This is great because now all I need to do is take grabs of the front, side and rear and I'm good to go for most humanoid characters which is what I do mainly. I can always work in 2D mode in DP3D and paint on my base bump and color maps in a single pass. :)

leigh
07-29-2003, 12:15 AM
Originally posted by ArneK
Discreet released Max 6 today and there are indeed some cool features included also in regards of texturing:

" …Paint Studio: New integrated 3D painting system for the creation of texture and other maps. Includes support for multiple layers, painting on multiple channels and across multiple objects…"

It's actually just Deep Paint 3D. You already get a LW version of DP3D, and I think it's pretty cheap.

Jonathan
07-29-2003, 12:59 AM
One thing I find very troubling about Deep Paint 3D is the blur tool. Usually this means simply bluring the image, but in Deep Paint 3D 1.61, blurring also blends the colors which is HIGHLY undesirable. This happens when you blur with the brush which is cool in theory but in practice, causes problems. What deep paint 3D does do however is allow you to be an artist. Things like pressure and stroke are effectively taken into account so when applying human skin, the more pressure I use on my wacom, the darker the color gets. I find this to be a very human approach to texturing and surely other programs can do it also, however I've found it more effective in this particular program.

ArneK
07-29-2003, 01:22 AM
Hmm interesting.

I've never tried Deep Paint or its likes before. I'm on Mac OSX and I think only Zbrush is available for me. Deep Paint is PC only.
How is Zbrush in comparison? Any good? It it easy to move objects/textures back and forth between the packages (LW and Zbrush)?

Jonathan
07-29-2003, 01:28 AM
I've only just downloaded the Zbrush demo yesterday. Haven't taking it for a walk around the park yet.

Understanding however that Deep Paint 3D is now up the version 2.x and I'm still use 1.61. They could very well have addressed the filter issues.

Triple G
07-29-2003, 03:04 AM
For $395, there's Maxon's Bodypaint 3D (http://www.maxon.net/pages/dyn_files/dyn_htx/htx/bodypaint3d_e.html). Mac/Win compatible, and seems to offer a lot of the same features as Deep Paint 3d.

Jonathan
07-29-2003, 03:21 AM
Yeah, there's plenty of software options out there. That's a good thing. I heard good things about Body Paint. Many people swear by it. Maxon creates BodyPaint IIRC. Perfect those using C4D. I bet theres a pipeline to that app.

Triple G
07-29-2003, 04:15 AM
Actually, according to the site, there are direct connections to C4D (since it's Maxon's product as well), as well as Lightwave and Max. :thumbsup:

ArneK
07-29-2003, 09:42 AM
Thanks! What seems great about Bodypaint is that supports direct import/export of Lightwave objects on the fly, and not just .obj and .dxf files as Zbrush. I'll download the demo and take it for a spin :)

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