Nyancat mod integration

The nyancat mod is not published at Minetest's content database and not in minetest_game,
so a successful installation of the nyanland mod is difficult.
To avoid this dependency difficulty,
the nyancat mod can be embedded into the nyanland mod.
The nyancat mod is already added as a subtree but not yet integrated.

Changes by this commit:
* Execute the embedded nyancat mod code if there is no other nyancat mod installed and modify the mod such that the embedding works
* Disable legacy nyanland and nyancat code by default and add settings to enable them if needed
* Reduce the nyancat:nyancat fall damage
* Some changes to satisfy luacheck

.luacheckrc

@@ -1,13 +1,5 @@
 read_globals = {"minetest", "vector", "math", "table",  "ItemStack", "dump",
 	"VoxelArea", "VoxelManip", "PseudoRandom",
 	"default", "treecapitator",
-	nyancat = {
-		fields = {
-			place = {
-				read_only = false,
-			}
-		},
-		other_fields = true
-	}
 }
-globals = {"nyanland_height"}
+globals = {"nyancat", "nyanland_height"}

LICENSE.txt

@@ -2,6 +2,8 @@ Code:
 
 The mod this is based on was licensed under GPLv3 and can be found in the 0.3
 branch and at https://forum.minetest.net/viewtopic.php?t=658.
+License of the embedded nyancat mod (see nyancat/license.txt):
+SPDX-License-Identifier: LGPL-2.1-or-later
 License of my changes:
 SPDX-License-Identifier: MIT
 
@@ -10,6 +12,7 @@ SPDX-License-Identifier: MIT
 Textures:
 
 SPDX-License-Identifier: CC-BY-SA-3.0
+See nyancat/license.txt for the authors of the nyancat_* textures.
 
 
 

depends.txt

@@ -1,3 +1,3 @@
 default
-nyancat
+nyancat?
 treecapitator?

init.lua

@@ -1,3 +1,6 @@
+local modpath = minetest.get_modpath"nyanland"
+dofile(modpath .. "/nyancat/init.lua")
+
 local settings = {
 	height = tonumber(minetest.settings:get"nyanland.height") or 30688,
 	nyancat_prop = (tonumber(minetest.settings:get"nyanland.nyancat_prop")
@@ -589,17 +592,14 @@ end
 
 
 nyanland_height = settings.height
-dofile(minetest.get_modpath"nyanland".."/portal.lua")
+dofile(modpath .. "/portal.lua")
 
 
--- legacy
+if not minetest.settings:get_bool"nyanland.enable_nyanland_legacy" then
+	return
+end
 
 minetest.register_entity("nyanland:tail_entity", {
-	--[[physical = false,
-	visual = "sprite",
-	timer=0,
-	collisionbox = {-0.5,-0.5,-0.5, 0.5,0.5,0.5},
-	visual = "cube",--]]
 	on_activate = function(self)
 		self.object:remove()
 	end

nyancat/README.txt

@@ -1,4 +1,4 @@
-Minetest Game mod: nyancat
+Modified Minetest Game mod: nyancat
 ==========================
 See license.txt for license information.
 

nyancat/depends.txt

@@ -1 +0,0 @@
-default

nyancat/init.lua

@@ -1,17 +1,23 @@
-minetest.register_node("nyancat:nyancat", {
+if minetest.global_exists("nyancat") then
+	return
+end
+assert(not minetest.registered_nodes["nyancat:nyancat"],
+	"Detected an incompatible nyancat mod")
+
+minetest.register_node(":nyancat:nyancat", {
 	description = "Nyan Cat",
 	tiles = {"nyancat_side.png", "nyancat_side.png", "nyancat_side.png",
 		"nyancat_side.png", "nyancat_back.png", "nyancat_front.png"},
 	paramtype = "light",
 	light_source = default.LIGHT_MAX,
 	paramtype2 = "facedir",
-	groups = {cracky = 2},
+	groups = {cracky = 2, fall_damage_add_percent = -88},
 	is_ground_content = false,
 	legacy_facedir_simple = true,
 	sounds = default.node_sound_defaults(),
 })
 
-minetest.register_node("nyancat:nyancat_rainbow", {
+minetest.register_node(":nyancat:nyancat_rainbow", {
 	description = "Nyan Cat Rainbow",
 	tiles = {
 		"nyancat_rainbow.png^[transformR90",
@@ -47,7 +53,7 @@ function nyancat.place(pos, facedir, length)
 	local tailvec = minetest.facedir_to_dir(facedir)
 	local p = {x = pos.x, y = pos.y, z = pos.z}
 	minetest.set_node(p, {name = "nyancat:nyancat", param2 = facedir})
-	for i = 1, length do
+	for _ = 1, length do
 		p.x = p.x + tailvec.x
 		p.z = p.z + tailvec.z
 		minetest.set_node(p, {name = "nyancat:nyancat_rainbow", param2 = facedir})
@@ -65,7 +71,7 @@ function nyancat.generate(minp, maxp, seed)
 	local volume = (maxp.x - minp.x + 1) * (y_max - y_min + 1) * (maxp.z - minp.z + 1)
 	local pr = PseudoRandom(seed + 9324342)
 	local max_num_nyancats = math.floor(volume / (16 * 16 * 16))
-	for i = 1, max_num_nyancats do
+	for _ = 1, max_num_nyancats do
 		if pr:next(0, 1000) == 0 then
 			local x0 = pr:next(minp.x, maxp.x)
 			local y0 = pr:next(minp.y, maxp.y)
@@ -80,10 +86,13 @@ minetest.register_on_generated(function(minp, maxp, seed)
 	nyancat.generate(minp, maxp, seed)
 end)
 
--- Legacy
+if not minetest.settings:get_bool"nyanland.enable_nyancat_legacy" then
+	return
+end
 minetest.register_alias("default:nyancat", "nyancat:nyancat")
 minetest.register_alias("default:nyancat_rainbow", "nyancat:nyancat_rainbow")
 minetest.register_alias("nyancat", "nyancat:nyancat")
 minetest.register_alias("nyancat_rainbow", "nyancat:nyancat_rainbow")
+-- luacheck: globals default
 default.make_nyancat = nyancat.place
 default.generate_nyancats = nyancat.generate

settingtypes.txt

@@ -8,6 +8,15 @@ nyanland.height (Height) int 30688 -32000 32000
 #    The radius of the nyanland tree heads
 nyanland.tree_size (Tree head size) int 2 0 80
 
-#    The change of generating a nyancat in a mapchunk
+#    The change of generating a nyancat in a mapchunk in the nyanland
 #    Value in percent (default 100%)
 nyanland.nyancat_prop (Nyancat probability) float 100 0 100
+
+#    Execute the legacy code of the embedded nyancat mod. This setting should
+#    only be enabled if compatibility problems occur with, for example, ancient
+#    worlds which have the default:nyancat node.
+nyanland.enable_nyancat_legacy (Enable nyancat legacy) bool false
+
+#    Execute legacy code for worlds which have used ancient versions of the
+#    nyanland mod. This setting should usually be disabled.
+nyanland.enable_nyanland_legacy (Enable nyanland legacy) bool false