Make default, tnt and dye all optional dependencies

player_api is now a dependency but it is more game-agnostic than default

api.lua

@@ -35,7 +35,7 @@ local function force_detach(player)
 		end
 		player:set_detach()
 	end
-	default.player_attached[player:get_player_name()] = false
+	player_api.player_attached[player:get_player_name()] = false
 	player:set_eye_offset({x=0, y=0, z=0}, {x=0, y=0, z=0})
 	player:set_properties({visual_size = {x=1, y=1}})
 end
@@ -53,9 +53,9 @@ function vehicles.object_attach(entity, player, attach_at, visible, eye_offset)
 		player:set_properties({visual_size = {x=1, y=1}})
 	end
 	player:set_eye_offset(eye_offset, {x=eye_offset.x, y=eye_offset.y+1, z=-40})
-	default.player_attached[player:get_player_name()] = true
+	player_api.player_attached[player:get_player_name()] = true
 	minetest.after(0.2, function()
-		default.player_set_animation(player, "sit" , 30)
+		player_api.set_animation(player, "sit" , 30)
 	end)
 	entity.object:setyaw(player:get_look_yaw() - math.pi / 2)
 end
@@ -64,8 +64,8 @@ function vehicles.object_detach(entity, player, offset)
 	entity.driver = nil
 	entity.object:setvelocity({x=0, y=0, z=0})
 	player:set_detach()
-	default.player_attached[player:get_player_name()] = false
-	default.player_set_animation(player, "stand" , 30)
+	player_api.player_attached[player:get_player_name()] = false
+	player_api.set_animation(player, "stand" , 30)
 	player:set_properties({visual_size = {x=1, y=1}})
 	player:set_eye_offset({x=0, y=0, z=0}, {x=0, y=0, z=0})
 	local pos = player:getpos()
@@ -78,6 +78,18 @@ end
 --mixed code(from this mod and lib_mount)
 
 
+-- Cache water and lava nodes
+local cache = { water = {}, lava = {} }
+minetest.register_on_mods_loaded(function()
+	for name, def in pairs(minetest.registered_nodes) do
+		if def.groups.water then
+			cache.water[name] = true
+		elseif def.groups.lava then
+			cache.lava[name] = true
+		end
+	end
+end)
+
 local vtimer = 0
 
 --New vehicle function, combines all of the others
@@ -141,7 +153,7 @@ function vehicles.object_drive(entity, dtime, def)
 	local accell = 1
 
 	--lava explode
-	if node == "default:lava_source" or node == "default:lava_flowing" then
+	if cache.lava[node] then
 		if entity.driver then
 			vehicles.object_detach(entity, entity.driver, {x=1, y=0, z=1})
 		end
@@ -153,10 +165,7 @@ function vehicles.object_drive(entity, dtime, def)
 	--respond to controls
 	--check for water
 	local function is_water(node)
-		return node == "default:river_water_source"
-			or node == "default:water_source"
-			or node == "default:river_water_flowing"
-			or node == "default:water_flowing"
+		return cache.water[node]
 	end
 	entity.on_water = is_water(node)
 	entity.in_water = is_water(minetest.get_node({x=pos.x, y=pos.y+1, z=pos.z}).name)

init.lua

@@ -9,6 +9,15 @@ local step = 1.1
 local enable_built_in = true
 
 if enable_built_in then
+
+local stone_sound = {}
+if minetest.global_exists("default") then
+	stone_sound = default.node_sound_stone_defaults()
+elseif minetest.global_exists("sounds") then
+	stone_sound = sounds.node_stone()
+end
+
+
 local function missile_bullet_hit_check(self, obj, pos)
 	local pos = self.object:getpos()
 	do
@@ -79,7 +88,9 @@ local function missile_on_step_auxiliary(self, obj, pos)
 				damage_groups={fleshy=12},
 			}, nil)
 		end
-		tnt.boom(self.object:getpos(), {damage_radius=5,radius=5,ignore_protection=false})
+		if minetest.get_modpath('tnt') then
+			tnt.boom(self.object:getpos(), {damage_radius=5,radius=5,ignore_protection=false})
+		end
 		self.object:remove()
 	end
 end
@@ -1842,6 +1853,8 @@ minetest.register_tool("vehicles:rc", {
 })
 
 --crafting recipes and materials
+-- (only if default and dye exists)
+if minetest.get_modpath("default") and minetest.get_modpath("dye") then
 
 minetest.register_craftitem("vehicles:wheel", {
 	description = S("Wheel"),
@@ -2243,8 +2256,7 @@ minetest.register_craft({
 	}
 })
 
-
-
+end -- end default and dye mod check
 
 
 --decorative nodes
@@ -2261,7 +2273,7 @@ function vehicles.register_simplenode(name, desc, texture, light)
 		groups = {cracky=1},
 		paramtype2 = "facedir",
 		light_source = light,
-		sound = default.node_sound_stone_defaults(),
+		sound = stone_sound,
 	})
 end--function vehicles.register_simplenode(name, desc, texture, light)
 
@@ -2291,7 +2303,7 @@ if minetest.get_modpath("stairs") then
 		{"vehicles_road.png"},
 		S("Road Surface Stair"),
 		S("Road Surface Slab"),
-		default.node_sound_stone_defaults())
+		stone_sound)
 end
 
 minetest.register_node("vehicles:neon_arrow", {

mod.conf

@@ -1,4 +1,4 @@
 name = vehicles
 description = A mod that adds an api for cars, planes, and other vehicles. Several vehicles are included in the mod.
-depends = default, tnt, dye
-optional_depends = stairs, creative
+depends = player_api
+optional_depends = default, tnt, dye, stairs, creative, sounds