$detail

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

$detail specifies a texture with which Source will add high-resolution detail when the material is viewed up close, by darkening or lightening the albedo appropriately, depending on the $detailblendmode. You can also use a full color (as opposed to grayscale) image and blend it using "$detailblendmode" "2". It is very effective for increasing the apparent resolution of a texture, and was used extensively in Episode Two. The effect is useable in all Source Engine based games.

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

Bug:Detail textures do not currently work in conjunction with $seamless_scale. Enabling them to work together would require a programmer to edit the used shader.  [todo tested in ?]

Syntax

$detail <texture>

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

Additional parameters

$detailtexturetransform <matrix>

Rotates, scales, etc. the detail texture. Requires DX9.

The default position is center .5 .5 scale 1 1 rotate 0 translate 0 0.

1. center defines the point of rotation. Only useful if rotate is being used.
2. scale fits the texture into the material the given number of times. 2 1 is a 50% scale in the horizontal X axis while the vertical Y axis is still at original scale.
3. rotate rotates the texture counter-clockwise in degrees. Accepts any number, including negatives.
4. translate shifts the texture by the given numbers. .5 will shift it half-way. 1 will shift it once completely over, which is the same as not moving it at all.

Note:All values must be included!

Bug:Scaling the texture may cause odd issues where the Texture Lock tool in Hammer will not actually lock the texture in place.  [todo tested in ?]

Bug:Rotating textures applied on brushes will rotate around the map origin (confirm: Orangebox engine only?). A fix for this is to change the center position in the VMT to the brush's origin.  [todo tested in ?]

$detailscale <float>

Fits the detail texture onto the material the given number of times (default = 4). Generally used instead of $detailtexturetransform with a value of around 7 or 8 for a 128px detail texture.

$detailblendfactor <normal>

Effectively an $alpha value for the detail texture.

$detailblendmode <int>

How to combine the detail material with the albedo.

There are 12 different detail blend methods that can be used. Taken from common_ps_fx.h

• 0 = original mode

• 1 = ADDITIVE base.rgb+detail.rgb*fblend

• 2 = alpha blend detail over base

• 3 = straight fade between base and detail.

• 4 = use base alpha for blend over detail

• 5 = add detail color post lighting

• 6 = TCOMBINE_RGB_ADDITIVE_SELFILLUM_THRESHOLD_FADE 6

• 7 = use alpha channel of base to select between mod2x channels in r+a of detail

• 8 = multiply

• 9 = use alpha channel of detail to mask base

• 10 = use detail to modulate lighting as an ssbump

• 11 = detail is an ssbump but use it as an albedo. shader does the magic here - no user needs to specify mode 11

• 12 = there is no detail texture

$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>

WorldVertexTransition only. When enabled, causes the level of detail alpha to determine "base texture blending".

Todo: Which base texture?

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