Defines the internal color depth (4, 16, 24, or 32 bit per pixel) of alpha channel
TGA based textures (d3d_alphadepth), level shadow maps (d3d_shadowdepth), PCX/BMP based
16 bit textures (d3d_texdepth), or sky cubes (d3d_skydepth).
4 - 4 bit color depth (compressed).
16 - 16 bit color depth (default of d3d_texdepth).
24 - 24 bit color depth (default of d3d_shadowdepth
32 - 32 bit color depth (default of d3d_alphadepth).
- Setting any color depth
to 4 stores the textures in a compressed DXT format if supported by
the 3D hardware. This can result in color artifacts and longer loading
time due to the compression process. Compressed textures can not be
accessed by pixel instructions.
- DDS textures
are already DXT compressed and thus do not require processing when
- 24 bit PCX and BMP images are normally stored
in 16 bit color depth, but can be stored in 24 bit by setting
d3d_texdepth at 24.
- 24 bit TGA textures
are always stored in 24 bit color depth (
except for sky cubes when
d3d_skydepth is set at 4). They can be used for textures that
require high image quality.
- Setting a color depth
variable before loading a level affects the textures and shadow
maps of this level and its entities.
d3d_alphadepth = 16; // set all TGA alpha images to 16 bit mode
d3d_texdepth = 4; // compress all except TGA based textures
d3d_texdepth = 24; // render PCX and BMP images in 24 bit mode