[Sypher_5]

I make a shape from poly's built off an original primitive and then to make sure its symetrical I delete one side and mirror the object as a copy. I attach both meshs together once they're lined up correctly. I select all vertices and weld every single one to make sure I have no extra vetices lying around.

Now even though I've been careful and tried to make sure I have one poly between each 3 vertices I cant help but wonder if I mave have got two in one spot or another. Maybe where I joined each part to the other.

What the best method to go back over this and check I havent got any reduntdant polys adding up in my model in GMAX ?

[Proclone]

In that example you'd have no redundant polies even if you didn't weld the vertices... You're confusing edges with faces...

The only thing you eliminate when welding verts between two halfs are the extra verts themselves and the edges between them... there's no face reduction at all.

[Sypher_5]

Hmm, I'll try explain another way.



Say that I'm going to attach these two boxes which have both ben cut in half. Now the one on the right has that bit extra still on it.

When I overlay them at the same point and weld all the vertices will the red face be one or will it be 2, comprised of the red one and the right ones overhang/extra piece ? Or will it dissapear while welding the vertices ?

This is something I've always wondered.

[Proclone]

er... who shot who in the what now?

You must be speaking elvin or something mr. middle earth because that didn't really make much sense. what overhang? and how could one become two? o.O

If you welded those you'd just get a normal box with 4 triangles on the top....

[Sypher_5]

Overhang - I was meaning the right box that has the extra face sticking out of it.

So when I weld the vertices that extra face is just thrown away as it were ? It doesnt have a duplicate face there ?

[Proclone]

by welding all of the shared verts together you effectively make the two faces into one face since the verts are what defines the faces...

EXCEPT when the normals of the faces are opposite each other... then you could end up with two faces sharing the same 3 verts.. but if that were the case it would be pretty easy to tell since you'd be able to see the face from both sides rather than only one side as is normal.

[Sypher_5]

I sort've figured that but wanted to make sure.

Many thanks

[Flyby]

Using mirrored geometry is a convenient way to build symetrical objects (i use it myself), bit you'll need to check the centre line for redundant faces :

In most cases you'll be able to replace those mirrored faces that share an edge in on the middle line by 1 face instead of 2.

[Sypher_5]

Yup, I already realise that and follow that method. Only reason I asked my question was to get the question ( wether it removes unessacery facs or not ) out of the back of my mind. Its been there some time and popped up in my mind earlier today so I thought it was about time to get an answer

Thanks for the reply though

[Flyby]

there are several ways to check if you have double faces with opposite normals :

1) go in face-subobject mode and select all, then flip normals. All good faces will now be unvisible and those offending ones will be visible. just delete those.

2) run the STL check modifier on your model. It will tell you more about the integrity of your mesh.