Detail textures
Format: 24-bit TGA with Bottom-Left origin.
Location: gfx/detail/

Each map must have a mapname_detail.txt description file for detail textures to work. Format is:

texturename		detail/name.tga		detailtilesX	detailtilesY

Detail tiles (also sometimes referred to as "scale") values describe simply how many times detail texture fits inside the actual world texture on each axis.
Detail textures typically have 128*128 pixels resolution. They are best viewed when DP/TP (detail pixels per texture pixels) value is constant among all textures.
To help maintaining this proportion, I made a handy table for you:

texture pixels = detail scale
512 = 16.0
448 = 14.0
384 = 12.0
320 = 10.0
256 = 8.0
224 = 7.0
208 = 6.5
192 = 6.0
176 = 5.5
160 = 5.0
144 = 4.5
128 = 4.0
112 = 3.5
 96 = 3.0
 80 = 2.5
 64 = 2.0
 48 = 1.5
 32 = 1.0
 16 = 0.5
  8 = 0.25

here DP/TP = 0.03125 or 1/32


Example:
mytexture192x64		detail/mydetail128.tga	6.0	2.0

If the DETAIL texture is larger, you'll have to decrease the "scale" value:
mytexture192x64		detail/mydetail256.tga	3.0	1.0

If the SURFACE texture is larger, you'll have to increase it:
mytexture384x128	detail/mydetail128.tga	12.0	4.0
mytexture384x128	detail/mydetail256.tga	6.0	2.0

So all textures will be in perfect sync with detail texels.

~X~