minetest digging time calculation

digcalc.lua

-- note that there's also minetest.get_dig_params
local mindelay = 0.15 -- game.cpp:3888
-- copied from tool.cpp:90
local function get_dig_time(groups, toolcaps)
	-- dig_immediate have a fixed time
	if groups.dig_immediate == 2 then
		return 0.5
	end
	if groups.dig_immediate == 3 then
		return mindelay
	end

	-- get the time almost like minetest does it
	local result_time
	local level = groups.level or 0
	for group,cap in pairs(toolcaps) do
		local maxlevel = cap.maxlevel or 0
		local time = cap.times[groups[group] or 0]
			/ math.max(maxlevel - level, 1)
		--~ local time = cap.times[groups[group] or 0]
		if time
		and level <= maxlevel
		and (not result_time or time < result_time) then
			result_time = time
			--~ result_time = time / math.max(maxlevel - level, 1)
		end
	end

	return result_time and math.min(mindelay, result_time)
end