When using textures 2048 pixels necessarily include the conf.ini
TexCompress=2
TexFlags.TexCompressARBExt=1
I know S3TC texture compression reduces the memory footprint of the textures significantly, and normally I think compressed textures are a perfectly valid method of increasing resolution while keeping VRAM consumption within limits.
However, as far as I know, the S3TC compression algorithm that compresses the files "on-the-fly" is inferior in quality compared to pre-compressed files.
Is there any chance at all to make IL-2 support DXT compressed DDS files, in addition to BMP/TGA files? It would be a very exciting addition. It would, essentially, offer the memory savings of using S3TC compression, but since you would be able to process the file with higher quality compression utility, it would not have such a high effect on the general quality of the textures.
The thing is: S3TC
is the same thing as DXT compression. The data format is the same. However, the DDS (or Direct Draw Surface) file format is a container format that has the ability to store uncompressed bitmaps, compressed bitmaps (with various options), and even MIP maps to reduce shimmering effects.
DXT compression itself exists in multiple varieties, but of those, two are of highest interest: DXT1c, and DXT5.
DXT1c stores an RGB image in a compressed format, while DXT5 stores RGB similar to DXT1, and an alpha channel in addition. The quality of the compression can be significantly affected. High quality conversion takes more time, while fast conversion usually results in reduced quality. The S3TC algorithm in IL-2 is, as far as I know, optimized for speed to reduce the overhead loading time from converting bitmaps into compressed format. While all DXT compression formats are lossy, the quality setting can make a significant difference; unfortunately it seems like IL-2 1946 is only capable of reading BMP or TGA files.
However, the
graphics/i] part of the engine obviously can utilize compressed textures, as evidenced by the TexCompress=2 setting. Would it be within any realm of possibility to tweak the game into accepting already compressed files, and passing them directly to the GPU instead of re-compressing them beforehand?
I'm just thinking - if using the compressed texture override is necessary for use of this mod, why not look into ways of making the game make the most of it...