Add minetest.get_artificial_light and minetest.get_natural_light (#5680)

Add more detailed light detection functions, a function to get the artificial light (torches) and a function to get the sunlight as seen by the player (you can specify timeofday).

Co-authored-by: rubenwardy <rw@rubenwardy.com>

games/devtest/mods/testtools/init.lua

@@ -1,6 +1,8 @@
 local S = minetest.get_translator("testtools")
 local F = minetest.formspec_escape
 
+dofile(minetest.get_modpath("testtools") .. "/light.lua")
+
 -- TODO: Add a Node Metadata tool
 
 minetest.register_tool("testtools:param2tool", {

games/devtest/mods/testtools/light.lua

@@ -0,0 +1,22 @@
+
+local S = minetest.get_translator("testtools")
+
+minetest.register_tool("testtools:lighttool", {
+	description = S("Light tool"),
+	inventory_image = "testtools_lighttool.png",
+	groups = { testtool = 1, disable_repair = 1 },
+	on_use = function(itemstack, user, pointed_thing)
+		local pos = pointed_thing.above
+		if pointed_thing.type ~= "node" or not pos then
+			return
+		end
+
+		local node = minetest.get_node(pos)
+		local time = minetest.get_timeofday()
+		local sunlight = minetest.get_natural_light(pos)
+		local artificial = minetest.get_artificial_light(node.param1)
+		local message = ("param1 0x%02x | time %.5f | sunlight %d | artificial %d")
+				:format(node.param1, time, sunlight, artificial)
+		minetest.chat_send_player(user:get_player_name(), message)
+	end
+})