Lezing's DN3D Resource»Released projects»Extended Color Look-Up Table Pack
Duke has quite a limited set of look-up palettes what leads to considerable restrictions when making realistic or weird environments; for instance, there's no way to brighten a texture, desaturate or invert its colors.
Hex editing allows modifying PALETTE.DAT and LOOKUP.DAT files used by Build engine to introduce up to 128 palettes and shades. You just edit the color tables in a raster graphics editor, save them to a raw format and then insert raw data into the files. I used this trick when making LNGA mod's palette system. Afterwards I decided to make something fully compatible with conventional Duke maps; I hope that such mod will be useful to the mapping community.
The Extended Color Look-up Table Pack or ExtCLUT mod is a quick project designed to add new entries to the standard set of palettes and improve the translucency preserving compatibility with most Duke maps. See Readme.txt for details; also look over the test map.
Duke's palette with repeating colors highlighted. Since their RGB values are the same, some of them can be overridden to serve as special colors for various effects achievable via the translucency table. The mod reserves eight colors for this purpose.
Download the final ExtCLUT version here; unpack the archive into your Duke directory. Launch ExtCLUTm.bat to see new palettes in Mapster32; you'll have to choose 8-bit modes to see the special effects as well.
If you prefer a GRP-compiled version, here's one: