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Preferred UV Unwrapping Method

Jade · 2019-04-02T07:49:02

Hello everyone! Jade here. I am here wondering: How do all of you 3D artists out there UV unwrap your 3D models? I am asking as I have started working towards making my own game, and I've made a few pieces of furniture, and, every time I get to the unwrapping stage, I get stuck thinking about how best to unwrap the model. So far, I have come up with these key elements to consider when unwrapping: - Space (between islands and the borders) - Overlapping UV Islands - Scale - Location What I have been doing is, after making sure my model is in the appropriate position, I apply the new scale, rotation, and location, so the defaults are 1.0, (0,0,0), (0,0,0). Then I unwrap the models making sure each island is understandable and has its own spot on the map (each leg of a chair, each panel of a shelf, ect.) and that I use as much of the space as I can, trying not to break scale uniformity. If I need to scale any one thing to get things to fit, I make sure I scale everything, so the scale ratio of the UV maps is 1:1, or as close to 1:1 as I can get it. I also make sure there is at least 8 pixels of space between everything, in relation to a UV map placed on a 256x256 image texture. What is really bugging me with this is, as ideal as letting each face have its own unique texture spot is, I know it would drastically cut down on work, in terms of trying to draw on textures, if I overlap the UV Maps (overlap each leg of a chair on top of each other, cut a shelf in half and stack the halves, ect.). Where do you guys draw the line? Do you favor productivity or the uniqueness of each model more? Is there a great visual difference, in your opinion, of models that have identical textures on its different faces vs models that have faces that are all unique? Any and all thoughts are appreciated! Thank you all for reading! TL;DR: Describe personal UV Unwrapping workflow. Overlap identical UV Islands, or don't overlap anything? -Jade

2D and 3D Art Visual Arts

Started by JadeRode March 27, 2019 02:20 AM

12 comments, last by Brain 5 years, 2 months ago

LorenzoGatti

4,652

March 29, 2019 09:25 AM

Obvious tool and workflow questions:

Do you attach arbitrary textures to parts of the 3D models (allowing and favoring reuse of specialized textures, e.g. a "polished wood" image applied to most of a chair), presumably with a postprocessing step that automatically rebuilds a consolidated texture atlas, or do you start with an automatically generated blank texture map and paint it?
In the latter case, can you easily copy and paste texture portions between separate but compatible UV islands with the same shape and orientation? For example, your shelf UV map is full of slight shape differences and mirrored parts, complicating a nice rectangular layout.
How do you combine painted textures and automatically generated textures like ambient occlusion or lightmaps?

Omae Wa Mou Shindeiru

NeoBrea

March 30, 2019 02:08 AM

I think what should get unique UVs and what should overlap depends on how much time/quality you want to give to it.

For example, a wooden chair. If you are just planning on applying a generic tileable wood texture onto it, as long as the pixel density is consistent across the model, you might be able to get away with assigning UVs anywhere without regard to overlapping. This should also be pretty quick to do.

But, if you were planning to paint or bake a particular texture to it, then think about the similar parts of the model. The legs might all be the same, and if each leg is rotated/mirrored differently, then you could create a single leg and viewers might not be able to tell the difference. But the seat would probably have to have its own UV island, as you may want to give it a look that cannot be shared with the legs. This takes only a little bit of preplanning to figure out what the similar parts are and setting up UV islands accordingly, but will give betterrults than using a tileable texture.

Brain

19,059

April 02, 2019 07:49 AM

On 3/27/2019 at 6:31 AM, JoeJ said:

Finally you can reuse high frequency textures (grass, wood) more easily than low frequency (bricks, rocks) without visible repetition.

You can also use "macro texture variation", where you overlay a noise pattern onto the texture, in both your normal map and your diffuse map to make the detail of the texture seem far greater, and also to hide seams in tiled textures.

For example: