Graphics Modding

[Ghogiel]

@Ghogiel

I'm starting to believe from what I've seen that alpha channel in _n files is occlusion and proper specular maps are _m files.

 

The _m is environment map mask. I am 100% positive. aka reflection map mask.

 

I don't know what experience with them you have.. and what you know about them in previous Bethesda games. But that is what they are. You just might not be clear on what the function of cubemaps and how they work and can be modfied in this engine.

 

I'll to show you...

 

 

these images are from my environment mapping tutorials for F3.. that were on the nexus but the article section they were in was deleted and the back up is probably on my laptop with the broken monitor...

 

anyway this is an env map.

http://www.fallout3nexus.com/imageshare/images/209926-1259326989.jpg

 

This is what it looks like on my model with a totally white _m map, a mid tone spec, and a near black diffuse map... YES a black diffuse map. This is IN F3 game engine.

http://www.fallout3nexus.com/imageshare/images/209926-1259327039.jpg

 

if you do not use an _m map in previous games, then the spec map will be used to mask the environment (or reflection) maps effect.

 

eg:

http://i25.photobucket.com/albums/c85/lego-botz/other/EnvmapTests2.jpg

 

 

 

This is what happens in skyrim:

 

http://www.skyrimnexus.com/imageshare/images/209926-1322657664.jpg

 

Same thing.

 

Note the one on left is a black _m map. One on right is _white. Note that specular highlights still exist on the one with black _m. Note that the Env map effect on the cloth areas on the whit map one.

 

if I leave the white _m map on and change the cubemap to my test one I get this:

 

http://www.skyrimnexus.com/imageshare/images/209926-1322660629.jpg

 

 

there appears to be a blur on the _e map. I tried finding if one of the unknowns in the material was a env map blur, not an uncommon parameter in dx shaders, but no luck yet...

 

About the blend alphas in terrain. Cheers for the research, :thumbsup: I cannot give feed back on it. not looked hard enough. good work though.

Edited November 30, 2011 by Ghogiel

[Witcher79]

Yeah. My experience is more tied with UDK and Maya than Bethesda games really. What buggers me though is that there's no chance for any other color than shades of gray in Beth specular layer (for creating non-metallic reflections for example). That's what led me to (false) belief that _m would be specular/enviro and _n would be more like parallax occlusion thing.

 

I'm fairly familiar with cubemaps but thanks for explanation anyway. Just a thought - maybe enviro blur is tied somehow with bUseWaterReflectionBlur from Skyrim.ini? Water uses CubeMap reflections too (bUseCubeMapReflections=1 and fCubeMapRefreshRate). Either that or there's some value in shaders001.fxp file. I would love to have that one fully readable...

[Ghogiel]

could be about the blur.

 

also note that vertex color also acts as an _m map... sort of. even if the diffuse is yellow, without vertex color and no _m map, somethings are greyed... but when white vert paint is added, then it'll beam like dwarven on the right... haven't got my head completely around that one yet.

Edited November 30, 2011 by Ghogiel

[throttlekitty]

@ThrottleKitty

Well maybe shader 11 is a "water flow"/"waves" shader then? Looks like that for me anyway.

 

Thanks for all your hard work on nifskope updating. Really appreciated. *bows*

Whoops, all that and I forgot to mention it's the ice shader, some of that was written while I was still toying around with it, and thanks! I'd probably call it "subsurface parallax" cos that's kind of descriptive and sounds sexy.

 

Also what I've seen so far is that alpha in normal diffuse textures is treated as 0/1 switch. So if we understand alpha as 0 - 255 value engine reads as 0-->127 = 1 (invisible) and 128--->255 = 0 (visible).

That's why moss or snow for example have that odd blending issue and in alpha channel you can see different alpha shapes blended with each other. Engine "adds" different shades of grey and creates output depending on final result:

Could be, I haven't paid enough attention to that in-game.

 

I have noticed jacked-up 'Threshold' settings in some of the AlphaProperties on some models, which would treat everything below the set number as 0. (seen values of 127 often) In previous titles, it was generally used to account for triangle sorting problems within a model, to tighten up the display 'errors'.

Given all the layered transparency in the game, maybe it was an early design decision to keep things running smoothly and reduce load increase from the alpha blending side of things.

[happy_spike]

I making new meshes for my jewellery mod and using 3ds max with nif exporter and nifskope. I have copied over the NiTriShapeData and created a new object. I couldn't get it to work and it kept crashing, then out of the blue while i was testing something else it worked, and looked fantastic. Next time i cursored over it though it crashed again. I have matched up whatever data I could find in another working nif but i can't get it to stop crashing. Any tips on how you got your stuff to stop crashing?

[throttlekitty]

Pretty much what you said, compare yours against a working nif until you can find a cause.

[Ghogiel]

Note about the body object space normal maps: orientation is X+ Y+. And they are swizzled, swap G with B.

[happy_spike]

I've narowed it down, it seems to be an issue with how the BSOrderedNode is layed out. Are there any rulse about how this is to be stuctured? I can get a normal mesh working but I want a transparent ice effect so I am copying the sapphire gem's .nif layout. It works on it's own but doesn't like it when I add the acual necklace part to the ordered node tree. If i make it from scratch it works the very first time I look at it but crashes every time after.

[Ghogiel]

The only rule I can think of using that node. it's just a ninode really, is that meshes are rendered in the order that they appear in the list, I presume it is simply for alpha sorting. Only add things to it if they are using alpha, amd order them so that inner most i at the top. Chuck any solid no alpha objects just under the scene root node, outside the orderednode, and make sure they are at the bottom of the block list.

[throttlekitty]

I'm thinking the snow layer on environment models is in the esm/esp. I figured it was a shader flag, since that makes sense, and many world models are broken down in a way that supports that idea. I doubt that the fact that the bedroll is underneath the tent matters. There are other objects (like barrels) that don't accumulate snow that aren't underneath something.

 

I was about and the end of my gaming session, and ended up in an imperial camp with tents and bedrolls, and figured this would be a good time to play around with this. The tent is one object and has snow, the bedroll is one object and does not have snow. Except that the shader flags are the same for both .nifs, I even copied the bedroll's data just in case. Thinking it had something to do with havok, I removed it entirely. Found the shader flag for vertex colors and removed those from the model. Nothing else in the .nif that I can see, and nothing tricky in the textures.