$envmap VMT parameter 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 exists in all Source Engine based games.
You will probably want to use at least
$detailscale (see below) as well.
Parameters and Effects
- Rotates, scales, etc. the detail texture. Requires DX9.
- The default position is
"center .5 .5 scale 1 1 rotate 0 translate 0 0".
centerdefines the point of rotation. Only useful if
rotateis being used.
scalefits the texture into the material the given number of times. '
2 1' is a 50% scale in the X axis.
rotaterotates the texture counter-clockwise in degrees. Accepts any number, including negatives.
translateshifts the texture by the given numbers. '
.5' will shift it half-way.
- 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.
- 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.
- Fits the detail texture onto the material the given number of times (default = 4). Generally used instead of
$detailtexturetransformwith a value of around 7 or 8 for a 128px detail texture.
- Controls the amount that the detail texture affects the base texture. The precise use of this depends on the blend factor; in most cases it acts similarly to $alpha. A value of 0 usually makes the detail texture have no effect, whilst a value of 1 applies the full effect.
- How to combine the detail material with the albedo.
There are 12 different detail blend methods that can be used.
The blend modes are implemented in
- 0 = DecalModulate
- This functions the same as the DecalModulate shader - colors below 128 darken the image, colors above lighten the image.
- 1 = Additive
- The color of the detail texture is added to the base texture. This is the same as $additive.
- 2 = Translucent Detail
- The detail texture is applied as a translucent overlay on top of the base texture.
- 3 = Blend Factor Fade
- The detail texture is applied as a transulcent overlay, but ignoring its alpha channel. Instead the blend factor is used to determine how much of the base texture shows through underneath.
- 4 = Translucent Base
- This effectively flips the normal layering of the two textures. The detail texture appears "below", with the base alpha channel controlling it as a translucent overlay. The detail alpha channel controls the overall material alpha - for translucency, masking or other uses.
- 5 = Unlit Additive
- The color of the detail texture is added to the base texture identically to mode 1, but this color is unaffected by lighting and therefore appears to glow.
- 6 = Unlit Additive Threshold Fade
- This adds color unnaffected by lighting like mode 5, but first modifies the colour added in two modes, depending on if the blend factor is above or below 0.5. To do: Screenshots of how this appears.
- 7 = Two-Pattern DecalModulate
- Only the red and alpha channels of the detail texture are used. This operates like the DecalModulate shader or blend mode 0, but the base alpha channel fades between using the red (0) or alpha (255) detail channel as the modulation source. This effectively allows two detail materials, although both are greyscale.
- 8 = Multiply
- The color of the base channel is multiplied by that of the detail texture.
- Bug: Not compatible with $phong due to missing shader combinations.
- 9 = Base Mask via Detail Alpha
- Only the detail alpha channel is used. It is multiplied with the base alpha channel to produce the final alpha value.
- 10 = Self-Shadowed Bumpmap
- The detail texture is used as a (possibly additional) $ssbump bumpmap. The blend factor is ignored.
- 11 = SSBump Albedo
- Unknown function, used internally. The comment says, "shader does the magic here - no user needs to specify mode 11".
- Any other values will disable the detail effect.
$detailtint "<RGB matrix>"
- Modifies the colour of the detail texture.
- Bug: Doesn't work.
- The frame to start animated detail texture on. Requires DX9.
WorldVertexTransitiononly. When enabled, causes the level of detail alpha to determine "base texture blending". To do: Which base texture? Is this actually fully implemented?
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
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 (
$detailscale is lower than the others. With the exception of
$detail detail\wood_detail_01 $detailscale 2.563 $detailblendfactor .8 $detailblendmode 0
Additionally, there are 2 other stock detail textures.
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