xray test

init.lua

local function xray(mode)
	XRAY_MODE = mode
end 

minetest.register_chatcommand("xray", {
    params = "<mode>",
    description = "Make stone invisible.",
    privs = {xray=true},    
    func = function(name, param)
        if param == 'on' then xray('on') 
          minetest.chat_send_player(name, "Xray turned on.") 
        elseif param == 'off' then xray('off') 
          minetest.chat_send_player(name, "Xray turned off.")
        else
          minetest.chat_send_player(name, "Please enter 'on' or 'off'.")
        end
    end,
})

minetest.register_abm({
        nodenames = {"default:stone", "xray:stone", "default:gravel", "xray:gravel"},
        interval = 0,
        chance = 1,    
        
        action = function(pos, node, active_object_count, active_object_count_wider)
          if XRAY_MODE == 'on' then
              if node.name == "default:stone" then
                  minetest.env:add_node(pos,{name="xray:stone"})
              elseif node.name == "default:gravel" then
                  minetest.env:add_node(pos,{name="xray:gravel"})
          else
              if node.name == "xray:stone" then
                  minetest.env:add_node(pos,{name="default:stone"})
              elseif node.name == "xray:gravel" then
                  minetest.env:add_node(pos,{name="default:gravel"})
                end
            end
        end
    end
})