After much discussion and a few words of wisdom from Cyryl we have decided to change from the traditional tga textures to direct draw surface (dds). The best thing about it is that it is already implemented in the Dark Places engine, however by default it is turned off, this will be fixed before the alpha release.
The main benefits are as follows:
A texture converted to dds format is less than half the file size of the original tga.
Mipmaps are generated and stored in the file, meaning that they don’t have to be done in real time, a significant performance increase is also expected.
The file is decoded by the video card rather than by software, which again should afford a significant performance increase.
While all this sounds great we are a little concerned that older hardware and even some of the new integrated chipsets may not support it. We don’t really have the means to test this extensively, if you would like to volunteer to test this please contact me at firstname.lastname@example.org
In the case that older hardware fails to support the dds format we have discussed making a utility to convert the dds files included in the game to tga files.
More as it develops