Crossover

mesecons/util.lua

@@ -14,6 +14,143 @@ function mesecon:move_node(pos, newpos)
 	minetest.env:get_meta(pos):from_table(meta)
 end
 
+--[[ new functions:
+mesecon:flattenrules(allrules)
+mesecon:rule2bit(findrule, allrules)
+mesecon:rule2meta(findrule, allrules)
+dec2bin(n)
+mesecon:getstate(nodename, states)
+mesecon:getbinstate(nodename, states)
+mesecon:get_bit(binary, bit)
+mesecon:set_bit(binary, bit, value)
+mesecon:invertRule(r)
+--]]
+
+function mesecon:flattenrules(allrules)
+--[[
+	{
+		{
+			{xyz},
+			{xyz},
+		},
+		{
+			{xyz},
+			{xyz},
+		},
+	}
+--]]
+	if allrules[1] and
+	   allrules[1].x then
+		return allrules
+	end
+
+	local shallowrules = {}
+	for _, metarule in ipairs( allrules) do
+	for _,     rule in ipairs(metarule ) do
+		table.insert(shallowrules, rule)
+	end
+	end
+	return shallowrules
+--[[
+	{
+		{xyz},
+		{xyz},
+		{xyz},
+		{xyz},
+	}
+--]]
+end
+
+function mesecon:rule2bit(findrule, allrules)
+	--get the bit of the metarule the rule is in, or bit 1
+	if (allrules[1] and
+	    allrules[1].x) or
+	    not findrule then
+		return 1
+	end
+	for m,metarule in ipairs( allrules) do
+	for _,    rule in ipairs(metarule ) do
+		if mesecon:cmpPos(findrule, rule) then
+			return m
+		end
+	end
+	end
+end
+
+function mesecon:rule2meta(findrule, allrules)
+	--get the metarule the rule is in, or allrules
+
+	if allrules[1].x then
+		return allrules
+	end
+
+	if not(findrule) then
+		return mesecon:flattenrules(allrules)
+	end
+
+	for m, metarule in ipairs( allrules) do
+	for _,     rule in ipairs(metarule ) do
+		if mesecon:cmpPos(findrule, rule) then
+			return metarule
+		end
+	end
+	end
+end
+
+if convert_base then
+	print(
+		"base2dec is tonumber(num,base1)\n"..
+		"commonlib needs dec2base(num,base2)\n"..
+		"and it needs base2base(num,base1,base2),\n"..
+		"which is dec2base(tonumber(num,base1),base2)"
+	)
+else
+	function dec2bin(n)
+		local x, y = math.floor(n / 2), n % 2
+		if (n > 1) then
+			return dec2bin(x)..y
+		else
+			return ""..y
+		end
+	end
+end
+
+function mesecon:getstate(nodename, states)
+	for state, name in ipairs(states) do
+		if name == nodename then
+			return state
+		end
+	end
+	error(nodename.." doesn't mention itself in "..dump(states))
+end
+
+function mesecon:getbinstate(nodename, states)
+	return dec2bin(mesecon:getstate(nodename, states)-1)
+end
+
+function mesecon:get_bit(binary,bit)
+	bit = bit or 1
+	local c = binary:len()-(bit-1)
+	return binary:sub(c,c) == "1"
+end
+
+function mesecon:set_bit(binary,bit,value)
+	if value == "1" then
+		if not mesecon:get_bit(binary,bit) then
+			return dec2bin(tonumber(binary,2)+math.pow(2,bit-1))
+		end
+	elseif value == "0" then
+		if mesecon:get_bit(binary,bit) then
+			return dec2bin(tonumber(binary,2)-math.pow(2,bit-1))
+		end
+	end
+	return binary
+	
+end
+
+function mesecon:invertRule(r)
+	return {x = -r.x, y = -r.y, z = -r.z}
+end
 
 function mesecon:addPosRule(p, r)
 	return {x = p.x + r.x, y = p.y + r.y, z = p.z + r.z}