unwrap uvw problem, need help

[mynmonic]

there's something wrong when i try to unwrap a tube with 48 sides & 5 height segments.

as u see in the image 01, the tube is actually an interior and i need to work on the internal faces (wall) to map the proper texture on it. there are 48 columns and 5 rows of tiles.

when i unwrap it i found that in the unwrap uvw editor, the tiles is vertically equally divided (5 rows are equal in height), but not horizontally equally divided (the 48 columns are not equal in width).

see the image 02, it's what i export it into jpeg.

i'm sure the tube model in max is equally divided the 48 sides, how can i fix the problem in unwrap?

please give me some hints, thx a lot for your time.

[mynmonic]

ok here's an additional image to explain my problem, i created a new tube with 48 sides and 5 height segments, converted to editable poly, added uvw map and choose cylindrical mapping, and then unwrap uvw and flattern the polygons i selected in the unwrap editor. that's what u can see my image below.

the white lines is the unwrapped object edges, the center tiles (quoted with red line) are always a bit larger than the tiles on 2 sides (quoted with green line).

i just don't get it why the object is equally divided in max but turn on various size in unwrap editor. i thought it was the problem that my first tube is boolean subtracted with a hole. therefore i created a new clean tube for testing and the same problem happen. any ideas? since i need to fill a pattern on each tile in photoshop, all the tiles are supposed to be the same size.

[Cad64]

Have you read through this tutorial: http://waylon-art.com/uvw_tutorial/uvwtut_01.html. It's a little dated, but the basics are there.

I'm at work now, so I can't really do much, but I will run some tests of my own tonight when I get home.

[Cad64]

Ok, let me see if I can explain this. :geek:
When you use "Flatten Mapping", your geometry gets projected onto a flat plane, so the shortening of the squares that you see is from the cylinder curving away from the plane. Just like when you look at the cylinder in "Front" view, the squares appear to get shorter as they curve away from you. One way to stop this from happening is to adjust the value of the "Face Angle Threshold" in the "Flatten Mapping" dialog. Lowering that value will break the UV's up into smaller clusters, thereby reducing or eliminating the shortening of the squares.

Or you could use "Unfold Mapping" instead of "Flatten Mapping".

[mynmonic]

oh yea, i noticed that it's sort of projecting a curved face on to a flat plane, i will try your suggestion when i back home, thanks for your answer.

this is my first post in the forum, i'm a max beginner.:P

[mynmonic]

ok i solved the problem by lowering the angel in flattern mapping, it's just turn out with more pieces i need to stitch them.

i will try the unfold mapping and see if it's more simple to do this.