rework loose node registration.

loose nodes are now automatically registrered when their settled
counterparts are. also rewrite a small amount of wrapper code and node
registration to work with this.

mods/bg_api/loose_node.lua

@@ -3,7 +3,7 @@ local function attempt_settle_at (pos)
 	if minetest.get_node(below).name == "air" then return end
 
 	local def = minetest.registered_nodes[minetest.get_node(pos).name]
-	minetest.set_node(pos, {name = def.stable_version})
+	minetest.set_node(pos, {name = def.settle_into})
 end
 
 -- settle nodes that are still (in the future, it will take some time for loose nodes that are still to settle).
@@ -17,22 +17,22 @@ blockgame.register_abm({
 
 
 
-function blockgame.register_loose_version (name)
-	local def = minetest.registered_nodes[name]
-	if not def then return false end
+local events = blockgame.events.namespace("api")
 
-	local groups = {}
-	for key, value in pairs(def.groups) do
-		groups[key] = value
-	end
-	groups.loose = 1
-	groups.can_fall = 1
+events.listen("before_register_node", function (data)
+	local name = data.name
+	local def = data.def
+	local mod = data.mod
 
-	blockgame.register_node(name .. "_loose", {
+	if not def.loose_variant then return end
+
+	blockgame.register_node(def.loose_variant, {
 		description = "Loose " .. def.description,
 		tiles = def.tiles, -- temporary
-		groups = groups,
-		stable_version = name,
-	})
-	return true
-end
+		groups = blockgame.underride({
+			loose = 1,
+			falling_node = 1
+		}, def.groups),
+		settle_into = mod .. ":" .. name,
+	}, mod)
+end)

mods/bg_api/wrappers.lua

@@ -34,8 +34,9 @@ end
 
 local events = blockgame.events.namespace("api")
 
-function blockgame.register_node (name, def)
-	local modname = minetest.get_current_modname()
+function blockgame.register_node (name, def, modname)
+	-- TODO: take full name and then extract modname and base name from that, that'll probably be easier to maintain.
+	local modname = modname or minetest.get_current_modname()
 	local full_name = modname .. ":" .. name
 
 	def.description = def.description or capitalize(name)

mods/bg_terrain/node.lua

@@ -15,7 +15,7 @@ blockgame.register_node("cobblestone", {
 		cracky = 3,
 		stoney = 1,
 	},
-	loose_variant = modname .. ":cobblestone_loose",
+	loose_variant = "cobblestone_loose",
 })
 
 minetest.register_alias("mapgen_stone", modname .. ":stone")
@@ -35,5 +35,5 @@ blockgame.register_node("dirt", {
 		dirty = 1,
 		grassable = 1,
 	},
-	loose_variant = modname .. ":dirt_loose",
+	loose_variant = "dirt_loose",
 })