Refactor pyramid type selection

init.lua

@@ -260,39 +260,12 @@ local function ground(pos, old)
 	end
 end
 
--- Attempt to generate a pyramid in the generated area.
+-- Select the recommended type of pyramid to use, based on the environment.
--- Up to one pyramid per mapchunk.
+-- One of sandstone, desert sandstone, desert stone.
-minetest.register_on_generated(function(minp, maxp, seed)
+local select_pyramid_type = function(minp, maxp)
-	if maxp.y < PYRA_MIN_Y then return end
-
-	-- TODO: Use Minetests pseudo-random tools
-	math.randomseed(seed)
-
-	if not perlin1 then
-		perlin1 = minetest.get_perlin(perl1.SEED1, perl1.OCTA1, perl1.PERS1, perl1.SCAL1)
-	end
-	--[[ Make sure the pyramid doesn't bleed outside of maxp,
-	so it doesn't get placed incompletely by the mapgen.
-	This creates a bias somewhat, as this means there are some coordinates in
-        which pyramids cannot spawn. But it's still better to have broken pyramids.
-	]]
-	local limit = function(pos, maxp)
-		pos.x = math.min(pos.x, maxp.x - PYRA_W+1)
-		pos.y = math.min(pos.y, maxp.y - PYRA_Wh)
-		pos.z = math.min(pos.z, maxp.z - PYRA_W+1)
-		return pos
-	end
-	local noise1 = perlin1:get_2d({x=minp.x,y=minp.y})
-
-	if noise1 > 0.25 or noise1 < -0.26 then
-		-- Need a bit of luck to place a pyramid
-		if math.random(0,10) > 7 then
-			minetest.log("verbose", "[tsm_pyramids] Pyramid not placed, bad dice roll. minp="..minetest.pos_to_string(minp))
-			return
-		end
-
 	local mpos = {x=math.random(minp.x,maxp.x), y=math.random(minp.y,maxp.y), z=math.random(minp.z,maxp.z)}
 
+	local sand
 	local sands = {"default:sand", "default:desert_sand", "default:desert_stone"}
 	local p2
 	local psand = {}
@@ -323,6 +296,51 @@ minetest.register_on_generated(function(minp, maxp, seed)
 			end
 		end
 	end
+
+	-- Select the material type by the most prominent node type
+	-- E.g. if desert sand is most prominent, we place a desert sandstone pyramid
+	if sand_cnt_max_id then
+		sand = sands[sand_cnt_max_id]
+	else
+		sand = nil
+		p2 = nil
+	end
+	return sand, p2
+end
+
+-- Attempt to generate a pyramid in the generated area.
+-- Up to one pyramid per mapchunk.
+minetest.register_on_generated(function(minp, maxp, seed)
+	if maxp.y < PYRA_MIN_Y then return end
+
+	-- TODO: Use Minetests pseudo-random tools
+	math.randomseed(seed)
+
+	if not perlin1 then
+		perlin1 = minetest.get_perlin(perl1.SEED1, perl1.OCTA1, perl1.PERS1, perl1.SCAL1)
+	end
+	--[[ Make sure the pyramid doesn't bleed outside of maxp,
+	so it doesn't get placed incompletely by the mapgen.
+	This creates a bias somewhat, as this means there are some coordinates in
+        which pyramids cannot spawn. But it's still better to have broken pyramids.
+	]]
+	local limit = function(pos, maxp)
+		pos.x = math.min(pos.x, maxp.x - PYRA_W+1)
+		pos.y = math.min(pos.y, maxp.y - PYRA_Wh)
+		pos.z = math.min(pos.z, maxp.z - PYRA_W+1)
+		return pos
+	end
+	local noise1 = perlin1:get_2d({x=minp.x,y=minp.y})
+
+	if noise1 > 0.25 or noise1 < -0.26 then
+		-- Need a bit of luck to place a pyramid
+		if math.random(0,10) > 7 then
+			minetest.log("verbose", "[tsm_pyramids] Pyramid not placed, bad dice roll. minp="..minetest.pos_to_string(minp))
+			return
+		end
+		local sand, p2
+		sand, p2 = select_pyramid_type(minp, maxp)
+
 		if p2 == nil then
 			minetest.log("verbose", "[tsm_pyramids] Pyramid not placed, no suitable surface. minp="..minetest.pos_to_string(minp))
 			return