The default surface type is stone. For all other surface types you will have to create shaders so that the impact sound/mark is correct for the material. Current surface types are as follows:
|stone (default)||puff of smoke, heavy boot on concrete surface sound|
|glass||usually on glass func_explosive entities|
|grass steps||brown bullet spray, springy footsteps|
|gravel steps||brown bullet spray, crunchy footsteps|
|metal steps||puff of smoke, clanky footsteps, metallic ricochet|
|roofs steps||clanky footsteps|
|snow steps||white bullet spray, crunchy footsteps|
|wood steps||puff of smoke, hollow steps|
A landmine is a small anti-personnel device used to blow up members of the opposing team. In order to allow players to place a landmine, there must be a floor surface with a surfaceparm type of landmine. This is a special surface type which can be used either on its own or with additional surfaceparm types.
As a rule only add the landmine surfaceparm to 'soft' materials like sand, earth etc. In the Enemy Territory game all wood / concrete / stone surfaces were excluded from landmine use.