Texture displays as diagonal lines,WHY?

[kmagill]

Hi,

Can someone explain what Maya is trying to tell me when I apply a material with a texture mapped to the color attribute to an object that it gets displayed as a series of diagonal lines?

I have it in my mind that its something to-do with hardware texturing.

This is currently only happening to objects I

[gmask]

It means that the object has no UV mappings

[zanzibar]

I have a similar problem.

I made a full human model, divided it symmetrically down the middle. Then I separated and extracted the head, arm, torso, leg and foot and in order to cut down the processing speed on the computer. I textured each piece and then after combining any of them, one of them always greys out.

Before combining, there was a UV map for each piece, afterwards only one shows up in the UV texture editor.

I don't want to have to go through all the texturing again as I was under the impression that this method worked.

Any clues?

[joojaa]

chek thet the dxf file has a uv intact.

As for the combined uving make sure all your uvs are part of the base uv map layer before merging.

Also if your multitexturing meka suer you understand that the viewport does not nnecceserily reflect the true settings.

[zanzibar]

Yes it turned out to be the UV map and UV sets:

• When I was projecting onto each separated section of the body, I wasn't sure when to make a new UV set and when not to, so I sometimes ended up with two UV sets for each Map, while on the head, there was only a map and no UV set!

So to fix it:

• Since I didn't know how to delete a UV set which didn't show any UVs, I went to a backed up model and reprojected the arm and torso. That left me with one map and one UV set per piece. The head only had a map and I didn't want to reproject that again as it was done in several stages.

• To fix the head I selected it and created an empty UV set in addition to the map which was already there. I then transferred over the UVs which showed up in the map for the head. Because there were now two sets of UVs for the head, I deleted the UVs assigned to the map.

• Now all pieces had a map with no UVs showing and a UV set where the UVs showed up.

• I then went and Combined all the pieces, stitched the head to the torso and stitched the two pieces of back of the arm together along their lengths.

Result:

a. The chequered pattern now flows better at the merged borders where it's been sewn together, but it looks as though one of each half which was stitched together is slightly in shadow. Where the shadow meets the piece it was combined to, it looks like the two halves are meeting at an angle instead of running seamlessly into eachother. The angle thing might just be a visual thing, because of the shadow, I'm not sure if it's really affected the topology. It renders out like this too.

b. The chequers meet badly where the arm meets the shoulder and where the arm has not been joined along it's length (the areas which haven't been sewn together). I take it that I won't be able to sew the arm to the torso because it'll mean overlapping UVs. I'm happy to paint it if that's the only way.

• Do you know if there's a good way round these two unsightly issues?

• If I have to paint over the bad joins, is it best done in Photoshop or within Maya?

• Lastly it is obviously clear that I don't really understand the difference between a UV map and a UV set. Was it necessary for me to have a map AND a set assigned to each piece that I was combining?

[drblacksnake]

• Lastly it is obviously clear that I don't really understand the difference between a UV map and a UV set. Was it necessary for me to have a map AND a set assigned to each piece that I was combining?

UVmap is general.. it may contain one or more UVsets.
Not necessarily for each piece - You could have a common set for both arms and another for both legs. Depends on complexity of both texture and geometry.

• Do you know if there's a good way round these two unsightly issues?

You can use same UVs for different sets so You can get UV overlapping at seams where gradient transparency applied makes a good blend between textures from different sets. So have one main set for torso and separate sets + 2-4 shared rows of UVs for each extremity. After use layered texture to combine last sets over main one.
NOTE: I haven't tested this on 6.0-6.5 but as far I've tried, earlier versions had no support for layered displacement maps for SW render. Perhaps MR supports it.

• If I have to paint over the bad joins, is it best done in Photoshop or within Maya?

Hard to generalize.. it depends on complexity of texture, particular join and Your skills aswell. Personally I use projections possible and bake, then retouch in pshop. This require a good UV layout too.

[zanzibar]

To fix the issue of the shadow, I selected the vertices along the offending seam and averaged their normals. That smoothed out the kink along the join.

All help and suggestions much appreciated. Thanks