Air Tight Modelling.

Submitted by Dan Ward on
Forum
Artists

Hi all,

Im pretty new to the whole modelling scene and had a question that i cant seem to get a clear answer on and was wondering if any of you guys could fill me in.

Question: How "Air Tight" should i be making my models? ie is it bad form to have seperate elements to your models or should they all be part of the one continuous mesh?

eg. lets say i have made a character .. and i want to be able to animate his/her/its eye balls .. is it ok to have the eyeballs as seperate elements that are placed within the head mesh or should they be a part of the head mesh? Do i leave the holes for the eye sockets open or should i seal them up so the head mesh is "air tight" even though you wouldnt be able to see the holes once the eyeballs are in place.

Is it ok to have overlapping elements to a model?

eg. Im adding a ammo belt to my character can i create it off to the side and then just place it on my character mesh or should it be APART of the charactermesh?

If i can just place it do i need to create the back faces so that its "air tight" even though they will never be seen?

Anyway if someone could shed some light on this i would really appreciate it.

Cheers

Submitted by Sorceror Bob on Sat, 15/03/03 - 12:43 AMPermalink

http://www.boomspeed.com/sorcerorbob/1.jpg

Dan, the simplest answer is to do what works best for you.
Creating an air tight mesh isn't necessary.. If I have faces that'll never get seen on a mesh, I'll get rid of them.
Eye balls - yup, thats a good way of doing it, its good to create the eye socket though.
In the above mesh, I often work with many seperate elements.. Everthing on the left arm are seperate elements, each strap, the boxes on the belt, the head armour, the thigh pads.... Most of it are seperate elements.

Its good to cap these, as they help add weight to the mesh.. But things like the leg straps I used on my model, you can get away without capping. The tubes also, the cap at the end was deleted..

I think I've jabbered on a bit at the end here.. If you need anything explained further, post it up.

Submitted by Dan Ward on Sat, 15/03/03 - 1:05 AMPermalink

Cool thanks for the speedy reply .. i kinda thought that was the case but its good to get some feedback :)

Submitted by Sorceror Bob on Sat, 15/03/03 - 2:32 AMPermalink

yup, the only bad thing about all those seperate elements is unwrapping.... ohh the humanity!!

Submitted by Dan Ward on Sat, 15/03/03 - 3:30 AMPermalink

Ack yeah UV wrapping is bad mojo .. as is rigging both of which i am yet to master

Submitted by StrkEagle on Sun, 16/03/03 - 9:25 AMPermalink

the way to get around the separate elements UV problem is to attach them all then unwrap it, then detach them

Submitted by Malus on Sun, 16/03/03 - 10:44 AMPermalink

I must be wierd because i really love uv mapping and rigging :|...honestly, put on some chilling tunes and just go.
Never had problems with uv mapping and seperate elements.

Submitted by Pantmonger on Sun, 16/03/03 - 8:20 PMPermalink

"the way to get around the separate elements UV problem is to attach them all then unwrap it, then detach them"

If all the parts are going to part of one model why would you attach them then detach them? Why not just leave them attached? Unless you where making a model that you wanted the different parts to animate around their individual pivot points. But for spikes n a backpack etc.

Pantmonger

Submitted by shiptu shaboo on Mon, 17/03/03 - 12:50 PMPermalink

the zen of uv wrapping

first make sure you make a multi sub object then name and colour all the elements before you even begin to uvw map.
then you wont get stray polys when you unwrap

nannoo nannoo

Submitted by Malus on Tue, 18/03/03 - 8:29 PMPermalink

Thats one way, I myself just select the faces, give them an id number and uvw map them ,then I hide them after and go to the next area, same sort of outcome different journey. :P

Submitted by Dan Ward on Wed, 19/03/03 - 8:00 PMPermalink

I havent worked out how to get the map as neat as you guys do it yet .. mine seem to come out alot more complicated then everyone elses that i have seen.

Ive got a few things i will try out on this challenge model that i havent done before hopefully they will work.

Submitted by StrkEagle on Fri, 21/03/03 - 9:44 PMPermalink

pants when you for instance goto texport a character and his eyeballs are a separate mesh but you want the all on one texture.
its easier to attach it and have all the mesh's UV on the one unwrap for texporting or equivalent
but hey i could be wrong :)

Peter Gillespie
www.3dluvr.com/eagor

Submitted by Malus on Fri, 21/03/03 - 10:50 PMPermalink

StrkEagle: unless the models for an fmv isn't it going to need to be one mesh, don't know of any game models that have seperated meshes, may be wrong there though.
If it is for an fmv why have it all on one map?

Submitted by StrkEagle on Fri, 21/03/03 - 11:30 PMPermalink

eyes were just an example
lok at mechwarrior, gran turismo etc, separate meshes, possibly single tex (correct me if i'm wrong)
look at gta3, max payne or half-life for example if you want to make in-game movies

Peter Gillespie
www.3dluvr.com/eagor

Submitted by Malus on Sat, 22/03/03 - 9:10 AMPermalink

are they seperate meshes or just seperate elements of one mesh?
Yeah I know how to make in game fmv's.

Submitted by Malus on Sun, 23/03/03 - 10:30 PMPermalink

I think the code can just seperate pieces of mesh, sort of like Unreal tournement 2003, which is a contigious mesh but when blown up it cuts the mesh up through code.

Submitted by Daemin on Mon, 24/03/03 - 2:03 AMPermalink

From what I remember the Mechwarrior 2 models were actually several different models joined together. I saw it in a viewer program that went into the packed files of theirs. They had a seperate model for the torso, each leg and arm, and one for the head (which really was just a glass panel of sorts).

But still, generally I'd say it doesn't matter how the models are created as long as there are no T-Junctions, and when rendered to the screen there are no visible holes. With the eyes example I wouldn't mind (being a programmer) having the eye sockets modelled, but if you could never poke out an eye then you wouldn't really need it.

Submitted by inglis on Mon, 24/03/03 - 2:39 AMPermalink

i dont do much lowpoly game modelling so im speaking from mainly higpoly experience.
but what i model isn't "air-tight", a characters body might well be- but a lot of the stuff i then build off them- for example straps around arms - i build them off the characters arm polys- so they dont have backfaces. basically- if you cant see it- dont bother.

but if you do make something that is "air-tight" and it passes an stl check i believe you can take it and get it moulded into a physical model. might cost a fair bit of mola - but would be cool :)

Posted by Dan Ward on
Forum
Artists

Hi all,

Im pretty new to the whole modelling scene and had a question that i cant seem to get a clear answer on and was wondering if any of you guys could fill me in.

Question: How "Air Tight" should i be making my models? ie is it bad form to have seperate elements to your models or should they all be part of the one continuous mesh?

eg. lets say i have made a character .. and i want to be able to animate his/her/its eye balls .. is it ok to have the eyeballs as seperate elements that are placed within the head mesh or should they be a part of the head mesh? Do i leave the holes for the eye sockets open or should i seal them up so the head mesh is "air tight" even though you wouldnt be able to see the holes once the eyeballs are in place.

Is it ok to have overlapping elements to a model?

eg. Im adding a ammo belt to my character can i create it off to the side and then just place it on my character mesh or should it be APART of the charactermesh?

If i can just place it do i need to create the back faces so that its "air tight" even though they will never be seen?

Anyway if someone could shed some light on this i would really appreciate it.

Cheers

Submitted by Sorceror Bob on Sat, 15/03/03 - 12:43 AMPermalink

http://www.boomspeed.com/sorcerorbob/1.jpg

Dan, the simplest answer is to do what works best for you.
Creating an air tight mesh isn't necessary.. If I have faces that'll never get seen on a mesh, I'll get rid of them.
Eye balls - yup, thats a good way of doing it, its good to create the eye socket though.
In the above mesh, I often work with many seperate elements.. Everthing on the left arm are seperate elements, each strap, the boxes on the belt, the head armour, the thigh pads.... Most of it are seperate elements.

Its good to cap these, as they help add weight to the mesh.. But things like the leg straps I used on my model, you can get away without capping. The tubes also, the cap at the end was deleted..

I think I've jabbered on a bit at the end here.. If you need anything explained further, post it up.

Submitted by Dan Ward on Sat, 15/03/03 - 1:05 AMPermalink

Cool thanks for the speedy reply .. i kinda thought that was the case but its good to get some feedback :)

Submitted by Sorceror Bob on Sat, 15/03/03 - 2:32 AMPermalink

yup, the only bad thing about all those seperate elements is unwrapping.... ohh the humanity!!

Submitted by Dan Ward on Sat, 15/03/03 - 3:30 AMPermalink

Ack yeah UV wrapping is bad mojo .. as is rigging both of which i am yet to master

Submitted by StrkEagle on Sun, 16/03/03 - 9:25 AMPermalink

the way to get around the separate elements UV problem is to attach them all then unwrap it, then detach them

Submitted by Malus on Sun, 16/03/03 - 10:44 AMPermalink

I must be wierd because i really love uv mapping and rigging :|...honestly, put on some chilling tunes and just go.
Never had problems with uv mapping and seperate elements.

Submitted by Pantmonger on Sun, 16/03/03 - 8:20 PMPermalink

"the way to get around the separate elements UV problem is to attach them all then unwrap it, then detach them"

If all the parts are going to part of one model why would you attach them then detach them? Why not just leave them attached? Unless you where making a model that you wanted the different parts to animate around their individual pivot points. But for spikes n a backpack etc.

Pantmonger

Submitted by shiptu shaboo on Mon, 17/03/03 - 12:50 PMPermalink

the zen of uv wrapping

first make sure you make a multi sub object then name and colour all the elements before you even begin to uvw map.
then you wont get stray polys when you unwrap

nannoo nannoo

Submitted by Malus on Tue, 18/03/03 - 8:29 PMPermalink

Thats one way, I myself just select the faces, give them an id number and uvw map them ,then I hide them after and go to the next area, same sort of outcome different journey. :P

Submitted by Dan Ward on Wed, 19/03/03 - 8:00 PMPermalink

I havent worked out how to get the map as neat as you guys do it yet .. mine seem to come out alot more complicated then everyone elses that i have seen.

Ive got a few things i will try out on this challenge model that i havent done before hopefully they will work.

Submitted by StrkEagle on Fri, 21/03/03 - 9:44 PMPermalink

pants when you for instance goto texport a character and his eyeballs are a separate mesh but you want the all on one texture.
its easier to attach it and have all the mesh's UV on the one unwrap for texporting or equivalent
but hey i could be wrong :)

Peter Gillespie
www.3dluvr.com/eagor

Submitted by Malus on Fri, 21/03/03 - 10:50 PMPermalink

StrkEagle: unless the models for an fmv isn't it going to need to be one mesh, don't know of any game models that have seperated meshes, may be wrong there though.
If it is for an fmv why have it all on one map?

Submitted by StrkEagle on Fri, 21/03/03 - 11:30 PMPermalink

eyes were just an example
lok at mechwarrior, gran turismo etc, separate meshes, possibly single tex (correct me if i'm wrong)
look at gta3, max payne or half-life for example if you want to make in-game movies

Peter Gillespie
www.3dluvr.com/eagor

Submitted by Malus on Sat, 22/03/03 - 9:10 AMPermalink

are they seperate meshes or just seperate elements of one mesh?
Yeah I know how to make in game fmv's.

Submitted by Malus on Sun, 23/03/03 - 10:30 PMPermalink

I think the code can just seperate pieces of mesh, sort of like Unreal tournement 2003, which is a contigious mesh but when blown up it cuts the mesh up through code.

Submitted by Daemin on Mon, 24/03/03 - 2:03 AMPermalink

From what I remember the Mechwarrior 2 models were actually several different models joined together. I saw it in a viewer program that went into the packed files of theirs. They had a seperate model for the torso, each leg and arm, and one for the head (which really was just a glass panel of sorts).

But still, generally I'd say it doesn't matter how the models are created as long as there are no T-Junctions, and when rendered to the screen there are no visible holes. With the eyes example I wouldn't mind (being a programmer) having the eye sockets modelled, but if you could never poke out an eye then you wouldn't really need it.

Submitted by inglis on Mon, 24/03/03 - 2:39 AMPermalink

i dont do much lowpoly game modelling so im speaking from mainly higpoly experience.
but what i model isn't "air-tight", a characters body might well be- but a lot of the stuff i then build off them- for example straps around arms - i build them off the characters arm polys- so they dont have backfaces. basically- if you cant see it- dont bother.

but if you do make something that is "air-tight" and it passes an stl check i believe you can take it and get it moulded into a physical model. might cost a fair bit of mola - but would be cool :)