Grimrock

I've been trying to follow the steps you guys have suggested, but I can't seem to get past the applying a texture to my model, and I'm not sure why my model gets progressively weirder as I try to put textures on it.

http://imgur.com/7kLir

This looks normal. The problem exists in the texture you are using. You have too much transparency. Try working on a black background instead of an alpha background

SUCCESS!

http://imgur.com/x5k71

It's doing wonky things in shadows, but I don't care. It's an anvil shaped object and it's grey and that's enough for me. I think I can show off my dungeon sometime this week after I test all my puzzles.

Thanks to everyone who posted, you all rule.

vorebane wrote:It's doing wonky things in shadows,

just an idea ...
load it back into the GMT and go to model and choose "Recalculate Tangents"
if they are missing then light/shadow will all get messed up.

Skuggasveinn.

Very happy you've got this one sorted out =D

With regards to lighting... There are a number of elements that can effect the shadows in the scene...

1. Normals describe how the light should be cast on / reflect at each vertex, and this data is used to calculate how lighting and shadow effect a face - if they are wrong, you can get crazy effects (like shadows appearing on the wrong side of things. While the GMT can calculate normals, it does it quickly and often badly - you are better off doing this step in your 3D modeller and ensuring the normals are exported into the .obj file.

2. Tangents/Bitangents affect how the normal map generates a 'bump effect' on the surface of polygons (mapped using UVs like the diffuse texture), showing scratches and bumps on the surface of the polygon. The GMT can generate these very well. Obj files CANNOT store this data - so if you use a normal map you should always click 'Calculate Tangents / Bitangents' after importing a new OBJ file before saving the .model file.

3. The specular map defines an objects 'shinyness' at each point on the faces (also mapped using UVs). Having a bad specular map might look a bit off but probably wouldn't completely mess up the lighting.

I've tried to describe these in an accessible way - apologies if the definitions are a bit 'fluffy'! I didn't think equations would be helpful :p.

Thanks for the video tutorial Skuggasveinn!