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BlackknightMartyr
08-13-2011, 10:19 PM
Alright, I'm terribly sorry to post this if it had been mentioned somewhere in the forums before. I did do some digging and couldn't find hard evidence on the subject.

Currently, I'm in school right now and learning 3DS Max and other programs. Recently I've had to do projects and require unwrapping. My only complaint is that I don't really grasp it quite yet. I looked at tons of tutorials, did a ton of research, even searched these forums for good advice. So, I have a good idea of how to do it and how it works... Though there is still a question going on in my head.

Why is flatten mapping bad?

Every time I talk to someone from school, I'm told it's bad. That it would stretch textures and the likes. Though, looking at tutorials ( 3d motive videos for example ) and from research I've done... It all used flatten mapping one way or another. And I'm talking about the actual "flatten mapping". Some people thought I was talking about "Quick Planar Map" at one point.

So I'd like people with better experience to tell me why it's bad.

sprunghunt
08-14-2011, 09:18 PM
flatten mapping tends to create a lot of unecessary UV islands. It also assumes that curved surfaces are planar which causes these unecessary splits.

I have seen people get a decent result from using flatten mapping and then stitching pieces back together. However that's the slow way to do it in my opinion. I prefer unfold or relax as I find these methods much faster.

renderhjs
08-14-2011, 09:30 PM
flatten a map might be your first entry into doing unwrapping. Its easier as real unwrapping as it defines the map seams for you and flattens every shell piece with a good ratio. The problem are the amount of seams on your 3D model and especially their random pattern. Seams can break your texture as it splits texels (3D pixels on a 3D surface) often in a obvious way.

Another way to break up a Model into UV shells is by splitting them according to smoothing groups of the model (so it places seams on hard edges). But booth are just the entry of unwrapping because after either of the 2 you have to start stitching those edges (islands) together where you don't want seams, or where it makes sense to connect them.

If all this doesn't make much sense, watch some introduction unwrapping videos, also perhaps related check out TexTools as it has some scripts that let you unwrap for example based on smoothing groups among other UV tools.
http://www.renderhjs.net/textools/