If you mean the purple human bug zapper things, then you can easily figure
it out from the map's entity setup. Get the ZHLT Power Tools and use
ripent or Botman's BSP Tool and export the map's entity data.
The outside Zapper uses 7 entities. This is the basic setup:
Place an env_laser in your map, set its targetname KeyValue to
flower_1, set the damage anount for the laser and most
importantly; set the LaserTarget KeyValue to player
(not sure if this is necessary since tanks only target players).
Make a func_tanklaser below this, set its laserentity KeyValue
to flower_1, set its target KeyValue to tsound_1. Make the
tanklaser invisible. Set its spawnflags KeyValue bitmask
to 1 (start active), do not make it controllable.
Set its targetname KeyValue to f1_kill.
Place an ambient_generic below this. The order isn't important,
just make sure all these entity origins are in the same X-Y co-ordinates.
Select an appropriate firing sound to play.
Set its targetname KeyValue to tsound_1.
Make a func_breakable, and set it's health. It should be centered
approximately where the laser would be firing from and large enough
for the Player to target it with a weapon.
Set its target KeyValue to f1_kill.
Place an env_sprite on or near the origin of the func_breakable.
Set an appropriate explosion sprite for this entity.
Set its targetname KeyValue to f1_kill.
Place a light_spot entity directly above the tank group setup.
Set it's orientation so that it points downward.
Set its targetname KeyValue to f1_kill.
Place a light_spot entity directly below the tank group setup.
Set it's orientation so that it points upward.
Set its targetname KeyValue to f1_kill.
This is how it works: the func_tanklaser finds a target and fires,
triggering the ambient_generic to play it's firing sound. The
env_laser is triggered wich damages the Player with its beam.
The two light_spot entities are just there to highlight the Zapper.
When the Player destroys the func_breakable, it triggers the
func_tanklaser and light_spot entities, turning them off.
The env_sprite is also triggered, playing the explosion sprite.
Here is the entity dump for 1 of the Zappers in c4a1:Key/Value : classname/env_laser
Key/Value : angle/90
Key/Value : targetname/flower_1
Key/Value : renderfx/0
Key/Value : LaserTarget/player
Key/Value : renderamt/200
Key/Value : rendercolor/137 30 164
Key/Value : width/10
Key/Value : NoiseAmplitude/40
Key/Value : TextureScroll/35
Key/Value : framestart/0
Key/Value : damage/5
Key/Value : texture/sprites/lgtning.spr
Key/Value : origin/264 712 -20
Key/Value : classname/func_tanklaser
Key/Value : angle/90
Key/Value : spawnflags/3
Key/Value : yawrate/100
Key/Value : yawrange/360
Key/Value : yawtolerance/15
Key/Value : pitchrate/100
Key/Value : pitchrange/15
Key/Value : pitchtolerance/5
Key/Value : barrel/8
Key/Value : spritescale/.8
Key/Value : firerate/1
Key/Value : persistence/4
Key/Value : firespread/0
Key/Value : renderfx/0
Key/Value : rendermode/2
Key/Value : rendercolor/123 49 215
Key/Value : laserentity/flower_1
Key/Value : minRange/64
Key/Value : maxRange/420
Key/Value : barrely/0
Key/Value : barrelz/0
Key/Value : spriteflash/sprites/xflare1.spr
Key/Value : target/tsound_1
Key/Value : renderamt/0
Key/Value : targetname/f1_kill
Key/Value : origin/264 712 -41
Key/Value : model/*80
Key/Value : classname/ambient_generic
Key/Value : spawnflags/52
Key/Value : health/7
Key/Value : preset/0
Key/Value : volstart/0
Key/Value : fadein/0
Key/Value : fadeout/0
Key/Value : pitch/110
Key/Value : pitchstart/100
Key/Value : spinup/0
Key/Value : spindown/0
Key/Value : lfotype/0
Key/Value : lforate/0
Key/Value : lfomodpitch/0
Key/Value : lfomodvol/0
Key/Value : cspinup/0
Key/Value : message/debris/beamstart10.wav
Key/Value : targetname/tsound_1
Key/Value : origin/264 712 -46
Key/Value : classname/func_breakable
Key/Value : health/120
Key/Value : material/3
Key/Value : explosion/1
Key/Value : delay/0
Key/Value : spawnobject/0
Key/Value : explodemagnitude/0
Key/Value : renderfx/0
Key/Value : rendermode/0
Key/Value : renderamt/0
Key/Value : rendercolor/0 0 0
Key/Value : target/f1_kill
Key/Value : model/*84Key/Value : classname/light_spot
Key/Value : _cone/32
Key/Value : _cone2/64
Key/Value : pitch/-90
Key/Value : _light/135 24 194 200
Key/Value : _sky/0
Key/Value : style/50
Key/Value : targetname/f1_kill
Key/Value : origin/264 712 -20
Key/Value : classname/light_spot
Key/Value : _cone/15
Key/Value : _cone2/20
Key/Value : pitch/90
Key/Value : _light/135 24 194 120
Key/Value : _sky/0
Key/Value : style/50
Key/Value : targetname/f1_kill
Key/Value : origin/264 712 -60
Key/Value : classname/env_sprite
Key/Value : spawnflags/2
Key/Value : renderfx/0
Key/Value : rendermode/5
Key/Value : renderamt/128
Key/Value : rendercolor/160 39 142
Key/Value : framerate/20.0
Key/Value : model/sprites/fexplo.spr
Key/Value : targetname/f1_kill
Key/Value : scale/.5
Key/Value : origin/264 712 -28