material_modify_control

material_modify_control is a point entity available in all Source games. It is used to modify arbitrary material properties in response to I/O events.

Class hierarchy
CMaterialModifyControl ↳CBaseEntity
MaterialModifyControl.cpp

For the entity to work, its target material must have the MaterialModify or MaterialModifyAnimated proxy installed, and must be applied to an entity.

Does similar things to the env_texturetoggle entity, which can control brushes or overlays by targetname.

Instances of the Material to Modify on world geometry are controlled by the lowest-ID (first created in Hammer) material_modify_control, in addition to instances of the material on the material_modify_control's parent.

Bug:The entity will not work unless it's parented to an object that's in the PVS, is on-screen, and has at least one face facing towards the viewer that's textured with the Material to modify.  [todo tested in?]

Keyvalues

Name (targetname) <string>

The name that other entities refer to this entity by, via Inputs/Outputs or other keyvalues (e.g. parentname or target).
Also displayed in Hammer's 2D views and Entity Report.

See also:  Generic Keyvalues, Inputs and Outputs available to all entities

Material to modify (materialName) <string>

Path to the VMT file you want to modify, relative to materials/ folder. Without .vmt suffix.

Bug:Does not work if the VMT is just in materials/. Should be in a subfolder, like materials/effects/ for example.  [todo tested in?]

Bug:When a material has a $envmap with env_cubemap as the value, this entity will appear to not work for that material. This is because VBSP will patch the original material and give it a different name that corresponds to the position of the closest cubemap to the brush face that has that material. This happens for every occurrence of the material. In order to make it work, you can replace the env_cubemap in your material with the path to the generated image of the closest cubemap. For example: env_cubemap "maps/yourmap/c124_28_-60". This means, however, that you will have to do it for every occurrence of the material you want to change, especially when you want them to use different cubemap images. This will make it so that VBSP will not try to patch the material and thus leave the original name. Another way is to just to directly specify the patched material name that is generated by VBSP, which you can find after unpacking the map file.  [todo tested in?]

Material variable to modify (materialVar) <string>

Name of the shader parameter you want to modify. Include the $ symbol like how they are written in the VMT.

Warning:When using VScript don't modify m_szMaterialName and m_szMaterialVar using NetProps.SetPropString. It won't work properly because of the way it's stored^[confirm]. Using AddOutputs or Set* inputs of this entity is required. The same applies to using NetProps.GetPropString which won't give you expected results.

Inputs

SetMaterialVar <string>

Sets the chosen material parameter to the specified value.

Bug:At least in , it doesn't convert given values to strings, so it can't accept inputs from entities which output anything else than string, math_counter or math_colorblend for example.  [todo tested in?]

Todo: Confirm in other games/engines and find workaround.

SetMaterialVarToCurrentTime

This sets the material variable to the current time on the server.

StartAnimSequence <string>

Force an animated material with the MaterialModifyAnimated proxy to play a set of animation frames.
Format is: <Frame Start> <Frame End> <Frame Rate> <Loop>
<Loop> should be 1 or 0.

Tip:Setting "Frame End" to -1 uses the last frame of the texture.

StartFloatLerp <string>

Force a material with the MaterialModifyAnimated proxy to linearly interpolate a material var between two floating point values.
Format is: <Start Value> <End Value> <Transition Time> <Loop>
<Loop> should be 1 or 0.

Note:For the linear interpolation to work correctly, you need both the MaterialModify and MaterialModifyAnimated proxies to be present.

Todo: There are some clarifications needed to be done about some quirks of this input.