Bump Mapping Problems.

Gibbage

3DS Max 2008

Im modeling a high detail space ship, and plan on baking it into a low poly model for game engines. For details like panel lines and rivits, I unwrapped the hull, and painted on a standard height map. It looks very good, except when you get in close.

Here you see the high poly model on the left, with the bump map.



On the right, is the low poly target.

When I render close, a seam forms on the panel lines were the UV seems are.



From a distance, you cant see them much if at all. But they are showing up on the normal map rendering. Here is a shot of the bump map, and the UVW's as they lay onto the texture.



This is very fustrating and is ruining a LOT of work. I really REALLY hope there is a fix for this! I have never had problems like this when using bump mapping. Please help.

Thanks in advance,

Gibbage

Coolhand

if tiny imperfections like that will bother you, why cut it through the panel when you could make it follow panel lines?

I think you should rework you UV's If you keep them as they are, normals will be the last of your problems as you'll end up with a visible seam line all along the object once you try and paint a colour map over that seam.

Gibbage

Its not a small imperfection. On the normal map, it shows up rather big. Im game, people will be that close too it anyways. I cant rework the UV's as I need to shoot them from the side and top in order to draw a straight panel line. If I pelt it with less seams, I cant draw a straight line at all.

spudmonkey

When you are rendering the projection maps are you doing it in Max? If so, are you using padding? Sometimes changing the padding settings will help with seams on normal maps. However, if you are using Max you might want to take a look at XNormal as it is much more powerful and tends to create more accurate maps

Gibbage

The seams happen before the projection mapping. Also, Xnormal does not support bump mapping like what im trying. It will only render a high polygon model onto a low polygon model, not the textures.

spudmonkey

The baking of the normal map is what seems to be going wrong here, so baking the normal in an external app and the diffuse/other maps in Max would be viable (Crazybump for converting height maps to normals for example). You could manually fix up the normal map in a 2d app by pasting or cloning a good area onto the bad area

If that doesn't help, can you show an image of the render to texture settings?

Coolhand

Gibbage wrote: »

I cant rework the UV's as I need to shoot them from the side and top in order to draw a straight panel line. If I pelt it with less seams, I cant draw a straight line at all.

Its perfectly possible to fix that very quickly in a UV editor without mangling the entire projection, depends how familiar you are with UV editing. And I didn't say anything about having less seams, just hiding this particular problem in a panel line, which is very close by to your UV seam and is the natural seam of the model.

It would be sensible to use this to make a natural seam line for the uv and you should habitually look to exploit those features to make a tidier model and your life easier in the long run. A seam like that can hamper the creation of your other maps, and even potentially cause further artifacting; like an ugly unwanted line in some real time engines, no matter how carefully you've painted your diffuse and other maps.

Shonner

For a game engine, this is really a minor problem with normal maps. Because the point after all is to be lo-poly anyway and rendered from a distance.