Glow Maps

[bencebence]

Hey everybody!

I'd need some help with glow maps.

I looked the whole internet and didn't found a really good tutorials (that doesn't mean I found none).

I followed a tutorial made for Morrowind, but it didn't work (added another texture to nifscope)

Then I tried to change the emissive color to white, then the whole sword was glowing.

 

I made the glow map with everything black only the glowing things was grayscale.

 

How can I make this work?

Thanks in advance,

bencebence

[alonsomartinez]

Save as _g.dds. Add it into the texture property in Nifskope.

[DrakeTheDragon]

As far as I know adding any aditional texture properties in NifSkope will not have any effect in Oblivion's version of the GameBryo engine. At least I haven't yet found 1 single glow-mapped item which did that, and when I did it myself just out of curiosity (intentionally "not" using the proper name, of course, else it would be pointless) it didn't have any effect. The only way Oblivion recognizes a glow map or normalmap is by the suffix "_g" ("_n" for normalmaps) to the filename, which has to match the regular texture's filename.

 

So for glowmaps to work for a texture like say "mytexture1.dds" in a NIF file you need to add a glow map named "mytexture1_g.dds" to the exact same folder "mytexture.dds" is in and give the according mesh in the NIF an "emissive" material property of white. Actually it doesn't even have to be white. Any color and intensity will do, the glow map just serves as a mask for which area it should glow through and how much.

 

Sadly I forgot which compression formats (DXT-1, DXT-3, DXT-5, uncompressed, etc.) were allowed for glow maps, but as with normalmaps it will not work with all of them.

 

You got your whole mesh glowing after setting the emissive property to white means it didn't find a glow map to mask the areas which should not glow. Likely you added the glow map in NifSkope instead of just giving it the proper filename.

 

Keep in mind though that there are several material names which are reserved and under control of the game engine. The most prominent would be "skin". Those will never accept any changes to the material properties as the game engine will immediately override them. As a matter of fact there can't be glow maps on body parts. Why this isn't the case for the also-controlled material of the heads though still eludes me. But I've long since learned to live with modding Oblivion having more exceptions than rules and anyways being just a bunch of inconsistencies. You just have to know them all at some point.

Edited July 28, 2011 by DrakeTheDragon

[bencebence]

Thanks both of you. I saved it in DXT1, and with _g suffix. I don't know what went wrong... I've also added it into the texture property in Nifskope.

So now I have these files in a folder:

runedsteelsword.dds

runedsteelsword_n.dds

runedsteelsword_g.dds

So I don't have to do anything, just play and the game itself will recognize them? Because in CS, it doesn't glow.

[Candex]

Always test this things in-game. The CS and Nifskope do not render in the same way. Sometimes the difference is slight... sometimes your texture is completely screwed and you wouldn't notice in the CS. Go play! :biggrin:

[bencebence]

Alright I tested ingame, and only the enchantment's light show up. The sword is plain, there is no lighting on it... Now I'll try with emissive color added.

Alright with emissive color set to white, it works fine. Thanks everyone :P

Edited July 28, 2011 by bencebence

[Pellape]

That link seems broken...

 

Glow maps have giving me gray hairs as well. To see what format a dds file is saved in, I use DXT2BMP as gimp fails to show it for sure... ;)

 

DXT2BMP cannot show you the _g.dds files but it does add or rather print out the format up at the top border in that app. To test it, well use the original glass arrows that have _g.dds and import it as well to gimp and export it without any compression as that might do the trick to get them to work. If I load it, it claims it is a Targa 32-bit picture so maybe that will do the trick? Save the file as a tga and rename it to dds??? When I load a Icon without compression, it still say it is a DDS 32-bit, not Targa.

 

Before we got DDS exporters or before we found DXT2BMP we used to make Targa files for Morrowind 17 years ago, which works but it also does not have the same quality as a dds if I recall right.

 

Well use this info and make some tests and also give us feedback how it goes. ;)

[glowplug]

This could use a tutorial.

 

As DrakeTheDragon posted years ago, the only texture read from the Nif by Oblivion is the diffuse - the engine simply loads the normal and glow if they are there.

 

While DXT2BMP has a lot of functionality, as an author, I am not interested in how a dds was saved. Just how to preserve and enhance it.

 

As Pellape posted, Targa (tga) was used by Morrowind and is lossless, okay for some smaller Morrowind textures, whereas dds is lossy due to higher compression - Morrowind mostly 512x512 or less - Oblivion mostly 1024x1024 or less. An increase 4 fold whereas average hardware had not quite increased to match that (without lag) in the interim. The dds loss is a trade off in order to get the files off hard drive faster then decompress on the GPU using DirectDraw .
While Morrowind did use dds, Oblivion did not use tga.

 

Diffuse Map - (TextureName.dds) the colored texture that is UV mapped to the mesh.
Normal Map - (TextureName_n.dds) used to fake bumps and dents through lighting - same UV Map as diffuse.
Glow Map - (TextureName_g.dds) pixel intensity (lightness) but no reflection on adjacent objects (other engines can reflect) - same UV Map as diffuse but does not have to follow contours.

Glow, often called emmisive. Often black and white (b&w) however color can be used.

PROBLEM:

• Export of (b&w) from GIMP to dds tends to posturize and/or set as grayscale (which can cause problems).

SOLUTIONS:

• Export to PNG (lossless) then convert using DDSOpt.
• Slight tint on white as we don't want black to glow (stop DDSOpt setting as grayscale).

DDSOpt Requirements.

• Installed to Oblivion game folder (eg. Oblivion/DDSOpt).
• 'In' folder under Oblivion/Textures (eg. Oblivion/Textures/DDSOpt).
• 'Out' folder under DDSOpt folder (eg. Oblivion/DDSOpt/Out).
• Game - Oblivion
• Compression - Maximum

NOTES:
The 'Install, In, Out' file structure allows DDSOpt to simply work things out.
We can change this but if it ain't broke...

Material:
Emissive Color - mixed with the _g.dds for rendered luminescence and color.

 

 

In Short:

• Tint white slightly to stop convert to GrayScale
• If using GIMP, export as PNG.
• Convert to dds using DDSOpt or other app if you know it.

Okay, it doesn't have to be PNG but if you know that then why did you spend your time reading down to here?

 

EDIT: I couldn't resist the opportunity for an...err...Glow Plug