Lowering Color depth.

[som99]

Hey all, i'm new here so ill start with saying hello and I love this site :)

 

Now to my problem, I just started tinkering with Fallout 3 textures, so bare with me.

I have a project I would like to work on but i'm stuck, the thing I want to do is to lower the color depth of all textures in Fallout 3 from 24bit to either 256 or 16 colors depending on what texture it is.

 

Why would I want to do that? Well because I have a passion of getting games to run on much lower spec systems then intended and setting lower color depth makes the textures a lot smaller in size, for example a big texture can take 1,3MB and reducing color depth can make it under half of that size (even less) thus making the game less VRAM heavy.

 

I have gotten the game to run fine in 320x240 resolution and with a slight tweak to fonts it will be 100% playable in that resolution :)

 

So that is my first part in the project, tho when I open a DDS file gimp loads up the main surface and mipmap's, no problems there, then I go to Image/Mode and select Indexed and change the maximum number of colors to 16 or 256 then hit convert.

 

Then when I want to save the image I hit Exort and replace the original DDS file.

Then I get an Message that says the following "DDS: It appears your image may be a volume map,

but not all layers are the same size, thus a volume map cannot be written"

 

So how do I change color depth in the fallout textures?

 

There must be an way to do this or will it work even tho I get the message?

 

Regards /som99

Edited May 8, 2012 by som99

[vforvic]

I don't use Gimp, but in Photoshop you don't want to load the mipmap's when working with the image. You load up the dds without the mipmaps, do your editing, and then generate them on save. I do know that dds wants a particular ratio in its size when saving. Loading the mipmap's messes up this ratio when you go to save again. In the case of Fallout 3 it wants a nice even square. Sounds like the error you are getting is from this issue.

[som99]

Thank's for your reply, I got photoshop CS5.1 x64 installed also and I added DDS extension support.

But when I load a picture without mipmaps how do I generate the new ones when I save?

 

Thanks again //som99

(Kudos for you)

 

EDIT:

Hmm I can't save at all in Photoshop, it tells me "Unsupported input format"

What plugin do you use?

 

Also will the textures work in fallout if I use BC1/DXT1 Compression, since if I do that I do not have to lower the color depth much since the images will be small anyways?

Edited May 9, 2012 by som99

[vforvic]

This is the Plugin for dds I use in Photoshop CS5.1 to open and save as well as do most Normal Maps. Nvidia I had a friend with the same issue and after he downloaded it again from here everything seemed to work for him.

 

When you go to save the dds there is an option to Generate Mipmaps or Not when you are picking the Compression.

 

For your purposes the Diffuse(color) map in DXT1 with no alpha is fine.

Now for Diffuse(color) maps with the need of alpha Transparency maps you should use DXT5, but I think you can use DTX3 as well in many of these cases.

In the case of Normal Maps that will need to contain a Specular Map in the alpha channel you will need to use DXT5. Now if you are not going to use a Specular Map, and just use a global specular level via the material on the mesh then you can use DXT1 no alpha.