need some advice on some normal mappin'

fritz

i'm about to normal map this canister thingy and i have a question. my main concern is the dome part on the top and how to go about properly unwrapping it. i've had weird issues w/dome shaped objects in the past and am wondering if anyone has any cool tricks. should i planar map from above? in the past i've tried that but the normals seem to go up and down in a wave-like pattern when viewed from the side.

any help would be greatly appreciated. thanks

StrangeFate

With things like that, i usually try to do 1 of 2 things:

1. Model a better shape less problematic to unwrap.
2. Put seams in the hipoly model where i think i'll need UV seams in the lowpoly.

You already have that so i'd UV map the top half flat (till that inset seam that goes around the model) then UV map the rest below in a normal fashion.

I've seen too what you mean, if you unwrap a cylinder with a flat projection there's so much distortion that the normals seem to get very broken when lit ingame.

I'd say you should be able to UV the top till that seam in the model without problems, i've unwrapped half domes with a flat projection from the top without breaking the normals (the stretching isn't pretty at that point tho).

Alternatively you can project the cap of the dome flat, you do have some details there that could hide the seam, and UV the rest of the dome nicely.

Whenever you model stuff that's complex to UV, make sure you put some detail (dark inset lines separating plates or bevels separating built pieces of an object) you think you'll be able to use to hide a UV seam later on.

When i model hioply, 50% of my thoughts while working are UV related and put a lot of smart 'UV detail' in.

fritz

yeah...i hear you about the modeling something that can potentially be a pain in the ass for UV's.

maybe i'll change it.

thanks a lot for chimin in. i appreciate it.

cheers

arshlevon

its all in how you set up the cage, check this pic.. on the first one you notcie the default wavy crap that happens when you just push the cage out... now check the second one, it looks pretty nice.. all you have to do is line up the cage loops exactly to the loops on your model.

look at the last pic.. the cage has been pushed out but notice the red lines are lined up right on top of where the edges are on the low. on a regular push they are either above or below this. its good to put edges on your low where you have ring type areas like this. if for instance you had a ring wrapping around the middle of your cylinder you could make the edge there to line up the cage and after you bake your normal you could delete that loop with no adverse affects. try it out..



okay now to show whats bad about this, look at the pic below, from the top the wavy one looks fine, but this new ones edges follow the edges of the low. its a trade off, i find that it depends on the object, and its scale, also the orintation you will see it. if you will only see this thing from the top, go with the default cage, if you are going to be seeing the side at all tweek the cage as mentioned above. i find the geometric edges are easier to overlook and look better than the wavy lines.

EarthQuake

i find a lot of the time with the wavy lines think you only really notice it when you're looking straight on, even with a slight angle its hard to notice unless you're specificly looking for it a lot of the time. So i would really only worry about it if its going to be at eye level.

fritz

thanks a lot for the feedback guys.

arsh: thanks so much for putting up an example. i owe you a pint.

arshlevon

fritz i will be coming to chicago soon, hopefully moving there, so i am totally taking you up on that.

sinistergfx

Chicago! YEAH!

arshlevon

oh snap sinistergfx too! holy crap we can talk mad shit about all those dickheads at mythic!!!!!!

YES!!!

fritz

well...i don't know anyone at mythic...but i sure can talk about some dickheads. seriously, i can grab a couple peeps from the surrounding game studios and we can go get some beers. i'll be looking out for a PM or something arsh.