$surfaceprop

The $surfaceprop command is used to tell Source what set of properties a surface has. It is found in both materials and QCs.

The surface prop controls many aspects of simulation:

• What sounds are emitted during collisions
• What effects are emitted when the surface is shot
• The surface's mass, buoyancy, bounciness...
• The effect of the surface on nearby sounds (reverberation, echo, absorption...)

Syntax

Syntax is the same in either context:

$surfaceprop <surface prop>

Surface props are defined in scripts/surfaceproperties_manifest.txt and the files linked to from there. For a list of Valve's stock props, see Material surface properties.

In materials

• $surfaceprop is not a shader parameter, so can be used on any material at all.

In models

• A model's surface prop will override its material's
• It is unclear whether a model's mass is calculated from it's surface prop or prop_data
• Surface props can be defined for individual bones with $jointsurfaceprop