Doom3world

When your normal map looks inverted you have to invert the Green channel of your normal map image. Just open it in photoshop, select the green channel and press Ctrl + I .

Sometimes you have to invert the red channel (if I remeber correctly), but the point is: every program creates normal maps in its own way, so you have to know which type of normal map your engine likes.

Let's do some examples:

DooM3 uses the sometimes called "ATi style normal maps", which have the green channel inverted in respect of Maya and Max normal maps.

Basically, to use a DooM3 created normal map in Maya, you have to invert the green channel of the image. Same thing, if you create a normal map in Maya, to use it in DooM3, you have to invert the green channel.

With this small info, it's really easy to work with normals: whatever your engine is, if your normal map looks inverted just open it in photoshop

But, that's not enough: You are using XNormal, and that's the best choice you can do with the hassle of creating normal maps: quick, simple to use, and it creates the best normal maps (it's second only to DooM integrated renderbump). In XNormal (like in Zbrush) you can choose, in the normal map tab, which channel you want inverted or not in your image file.

Ps: the problem in your last post seems like a UV problem; may you post your uv layout?

Renderbump is not too difficult to use, once you get how it works.

I haven't used it for a very long time but here is as I remember it. If I miss something, I'm sorry in advance. But this should be pretty much how it works.

Export both low and high poly to .ase or .lwo file. They must occupy the same space. You must export normals and UV info. Although UV is only used for the low poly.

Put both exported models in base/models

This location is not mandatory, so feel free to use your own location.

Make sure you have a Doom material that actually works for the low poly model. If the material does not work the renderbump will not work.

Then you need to add a line like this...


... to your material. This is the info to create the proper normal map and reference the high poly model.

I recommend to run Doom in windowed mode before rendering the map. The size there is the size of the map it saves out. The "aa" is anti-aliasing and I'll suggest to make it 0 for testing purpose to speed it up. Once you get a good result you can push it up for final renders. The trace is the distance it will trace for high poly normals. Tweak this if you are missing some normals or get some overlaps of close geometry. The next line is the file name of the TGA it'll save and the last bit is the reference to the high poly model

So then inside Doom you bring down the console and type..

renderbump models/lowpoly.ase

This of course needs to point to your low poly model. You can use TAB to just quickly pick through. I'm sure you know the TAB shortcut in the Doom console.

So that is pretty much it.

Main things are to have proper exports. Just to be safe you can keep them scaled in game dimensions. So it's not like super huge or really tiny. And of course the material has to work. I know lots of people struggle with that, not using material names correctly and so on.

I hope this is helpful and I didn't miss something important..

Sometimes normal maps in the real-time preview in Max look fubard just like that. It can be a glitch in the preview that occurs when it does not update correctly, and can be fixed by turning the DX material preview off, and then back on. I find using DX material previews often crashes Max. It could be just as buggy in Maya. I would worry about what the normal map looks like in Doom, and dont pay too much attention to how it appears in Maya.