CS2D
Scripts Supply item spawn on gate field
Supply item spawn on gate field
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) here's the link
object for it 
Joni And Friends provided. Try using the tile coordinates to check if a Gate Field is within a Supply. 
Loop all buildings If supply is found, do x|y loop from -1 to 1 Check if there's a building that's gatefield there If there isn't but there's a weapon near it, remove the weapon.
Supply item spawn on gate field
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for index, id in pairs(object(0, "table")) do
if (object(id, "type") == 9 or object(id, "type") == 15) then
for addtilex = -1, 1 do
for addtiley = -1, 1 do
local tilex, tiley = object(id, "tilex") + addtilex, object(id, "tiley") +add tiley
for index, itemid in pairs(item(0, "table")) do
if (item(itemid, "tilex") == tilex and item(itemid, "tiley") == tiley) then
if (objectat(tilex, tiley, 6) == 0) then
parse("removeitem " .. itemid)
end
end
end
end
end
end
end
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