Const TYPE_CUBE=1,TYPE_CONUS=2
Collisions TYPE_PLAYER,TYPE_SCENERY,2,2

For с.Conus=Each Conus ;цикл "пробежится" по всем объектам типа Conus
      UpdateCollisions( с )
     Next

;И функцию, которая скроет конус, который столкнулся с кубом

Function UpdateConus( c.Conus )
If EntityCollided( c\entity, TYPE_CONUS ) then ;в твоём коде  c\entity это stolb2
       EntityAlpha с\ent,0  ;скрывает конус
endif
end function

Graphics3D 640,480,16

SetBuffer BackBuffer()

Type Cubes
  Field entity
End Type

Const TYPE_PLAYER=1,TYPE_CUBE=2
Collisions TYPE_PLAYER,TYPE_CUBE,2,1

lit=CreateLight()
Global player=CreateCube()
EntityType player,TYPE_PLAYER

EntityColor player,0,255,0
EntityType player, TYPE_PLAYER

For x = 1 To 100
  t .Cubes = New Cubes
  t\entity = CreateCone()
  PositionEntity t\entity, Rnd(-120, 120), Rnd(0, 0), Rnd(-100, 100)
  EntityType t\entity,TYPE_CUBE
Next

EntityType t\entity,2
Collisions 1,4,2,1

cam=CreateCamera(player)
stolb=CreateCube()
ScaleEntity stolb,1,4,1
PositionEntity stolb,-7,0,7
EntityType stolb, 2
stolb2=CreateCube()
ScaleEntity stolb2,1,4,1
PositionEntity stolb2,7,0,7
EntityType stolb2, 3
Collisions 1,2,2,1
Collisions 1,3,2,1

plan=CreatePlane()
EntityColor plan,0,0,255

PositionEntity plan,0,-1,5
PositionEntity cam,0,3,-5

Repeat
If KeyDown(200) MoveEntity player,0,0,.2
If KeyDown(208) MoveEntity player,0,0,-.2
If KeyDown(203) TurnEntity player,0,1,0
If KeyDown(205) TurnEntity player,0,-1,0

  For t.Cubes=Each Cubes
   UpdateColl( t )
  Next
     
UpdateWorld
RenderWorld

Flip

Until KeyHit(1)

End

Function UpdateColl( t.Cubes )
   If EntityCollided( player, TYPE_CUBE ) Then
          EntityAlpha t\entity,0
   EndIf
End Function