$detail

A detail texture (noise_detail_01), and its effect when applied to a material (left).

$detail specifies a grayscale texture with which Source will add high-resolution detail when the material is viewed up close, by darkening the albedo appropriately. It is very effective for increasing the apparent resolution of a texture, and was used extensively in Episode Two.

Tip:A bump map can perform the same job as a detail texture, but is more expensive.

Syntax

$detail <texture>

You will probably want to use at least $detailscale (see below) as well.

Additional parameters

$detailscale <float>

Fits the detail texture onto the material the given number of times. Generally around 7 or 8 for a 128px detail texture; default is 4.

$detailblendfactor <normal>

Effectively an $alpha value for the detail texture.

$detailblendmode <int>

0 means darken the albedo. 1 means lighten it.

$detailtint "<RGB matrix>"

Modifies the colour of the detail texture.

$detailframe <int>

The frame to start animated detail texture on. Requires DX9.

$detail_alpha_mask_base_texture <bool?>

Todo: When $detail alpha is 0, don't blend with $basetexture?

Requires DX9.

Valve's detail textures

Valve's stock detail textures (available in OB only) are best used with the following pre-configured values:

$detail detail\noise_detail_01 // e.g. for brickwork, concrete...
$detailscale 7.74
$detailblendfactor 0.8
$detailblendmode 0

$detail detail\metal_detail_01
$detailscale 4.283
$detailblendfactor .65
$detailblendmode 0

$detail detail\rock_detail_01
$detailscale 11
$detailblendfactor 1
$detailblendmode 0

$detail detail\plaster_detail_01
$detailscale 6.783
$detailblendfactor .8
$detailblendmode 0

The below parameters come from models\props_forest\LadderWood.vmt It is the only Valve Stock texture VMT file to use this particular detail texture. Because the detail texture (detail\wood_detail_01) is a high resolution (1024x1024), the $detailscale is lower than the others. With the exception of rock_detail_01.

$detail detail\wood_detail_01
$detailscale 2.563
$detailblendfactor .8
$detailblendmode 0

Additionally, there are 2 other stock detail textures. detail\detailash001a and detail\detaildirt001a.

These files were used in the "leaked" version of Half-Life 2 & in Half-Life 2: Episode One using the following parameters;

(Concrete/concretefloor009a in Episode One materials)

$detail detail/detaildirt001a
$detailscale 0.27

(Metal/metalfloor005a in Episode One materials)

$detail detail/detailash001a
$detailscale 0.50