mcl_mapgen_core: Make mcl_flowers an optional dependency.

mcl_flowers was previously an undeclared dependency of mcl_mapgen_core.
Now it is both optional and declared.

mods/MAPGEN/mcl_mapgen_core/init.lua

@@ -1039,15 +1039,17 @@ local function register_mgv6_decorations()
 	end
 
 	-- Add a small amount of tall grass everywhere to avoid areas completely empty devoid of tall grass
-	minetest.register_decoration({
-		deco_type = "simple",
-		place_on = {"group:grass_block_no_snow"},
-		sidelen = 8,
-		fill_ratio = 0.004,
-		y_min = 1,
-		y_max = mcl_vars.overworld_max,
-		decoration = "mcl_flowers:tallgrass",
-	})
+	if minetest.get_modpath("mcl_flowers") then
+		minetest.register_decoration({
+			deco_type = "simple",
+			place_on = {"group:grass_block_no_snow"},
+			sidelen = 8,
+			fill_ratio = 0.004,
+			y_min = 1,
+			y_max = mcl_vars.overworld_max,
+			decoration = "mcl_flowers:tallgrass",
+		})
+	end
 
 	local mushrooms = {"mcl_mushrooms:mushroom_red", "mcl_mushrooms:mushroom_brown"}
 	local mseeds = { 7133, 8244 }
@@ -1091,46 +1093,48 @@ local function register_mgv6_decorations()
 		decoration = "mcl_core:deadbush",
 	})
 
-	local function register_mgv6_flower(name, seed, offset, y_max)
-		if offset == nil then
-			offset = 0
+	if minetest.get_modpath("mcl_flowers") then
+		local function register_mgv6_flower(name, seed, offset, y_max)
+			if offset == nil then
+				offset = 0
+			end
+			if y_max == nil then
+				y_max = mcl_vars.mg_overworld_max
+			end
+			minetest.register_decoration({
+				deco_type = "simple",
+				place_on = {"group:grass_block_no_snow"},
+				sidelen = 16,
+				noise_params = {
+					offset = offset,
+					scale = 0.006,
+					spread = {x = 100, y = 100, z = 100},
+					seed = seed,
+					octaves = 3,
+					persist = 0.6
+				},
+				y_min = 1,
+				y_max = y_max,
+				decoration = "mcl_flowers:"..name,
+			})
 		end
-		if y_max == nil then
-			y_max = mcl_vars.mg_overworld_max
-		end
-		minetest.register_decoration({
-			deco_type = "simple",
-			place_on = {"group:grass_block_no_snow"},
-			sidelen = 16,
-			noise_params = {
-				offset = offset,
-				scale = 0.006,
-				spread = {x = 100, y = 100, z = 100},
-				seed = seed,
-				octaves = 3,
-				persist = 0.6
-			},
-			y_min = 1,
-			y_max = y_max,
-			decoration = "mcl_flowers:"..name,
-		})
-	end
 
-	register_mgv6_flower("tulip_red",  436)
-	register_mgv6_flower("tulip_orange", 536)
-	register_mgv6_flower("tulip_pink", 636)
-	register_mgv6_flower("tulip_white", 736)
-	register_mgv6_flower("azure_bluet", 800)
-	register_mgv6_flower("dandelion", 8)
-	-- Allium is supposed to only appear in flower forest in MC. There are no flower forests in v6.
-	-- We compensate by making it slightly rarer in v6.
-	register_mgv6_flower("allium", 0, -0.001)
-	--[[ Blue orchid is supposed to appear in swamplands. There are no swamplands in v6.
-	We emulate swamplands by limiting the height to 5 levels above sea level,
-	which should be close to the water. ]]
-	register_mgv6_flower("blue_orchid", 64500, nil, mcl_worlds.layer_to_y(67))
-	register_mgv6_flower("oxeye_daisy", 3490)
-	register_mgv6_flower("poppy", 9439)
+		register_mgv6_flower("tulip_red",  436)
+		register_mgv6_flower("tulip_orange", 536)
+		register_mgv6_flower("tulip_pink", 636)
+		register_mgv6_flower("tulip_white", 736)
+		register_mgv6_flower("azure_bluet", 800)
+		register_mgv6_flower("dandelion", 8)
+		-- Allium is supposed to only appear in flower forest in MC. There are no flower forests in v6.
+		-- We compensate by making it slightly rarer in v6.
+		register_mgv6_flower("allium", 0, -0.001)
+		--[[ Blue orchid is supposed to appear in swamplands. There are no swamplands in v6.
+		We emulate swamplands by limiting the height to 5 levels above sea level,
+		which should be close to the water. ]]
+		register_mgv6_flower("blue_orchid", 64500, nil, mcl_worlds.layer_to_y(67))
+		register_mgv6_flower("oxeye_daisy", 3490)
+		register_mgv6_flower("poppy", 9439)
+	end
 
 	-- Put top snow on snowy grass blocks. The v6 mapgen does not generate the top snow on its own.
 	minetest.register_decoration({

mods/MAPGEN/mcl_mapgen_core/mod.conf

@@ -2,4 +2,4 @@ name = mcl_mapgen_core
 author = Wuzzy
 description = The core of the MCL2 mapgen
 depends = mcl_init, mcl_core, biomeinfo, mcl_worlds
-optional_depends = mclx_core, mcl_cocoas, mcl_sponges, mcl_ocean, mcl_stairs, mcl_monster_eggs, mcl_structures
+optional_depends = mclx_core, mcl_cocoas, mcl_sponges, mcl_ocean, mcl_stairs, mcl_monster_eggs, mcl_structures, mcl_flowers