many worldgen mods and gonna try technic now

mods/dfcaverns/mapgen_helper/random.lua

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+
+-- Returns a consistent list of random points within a volume.
+-- Each call to this method will give the same set of points if the same parameters are provided
+mapgen_helper.get_random_points = function(minp, maxp, min_output_size, max_output_size)
+	local next_seed = math.random(1, 2^21) -- should be 2^31, but I've had a report that this causes a crash in the Lua interpreter on some systems.
+	math.randomseed(minetest.hash_node_position(minp) + mapgen_helper.mapgen_seed)
+	
+	local count = math.random(min_output_size, max_output_size)
+	local result = {}
+	while count > 0 do
+		local point = {}
+		point.x = math.random(minp.x, maxp.x)
+		point.y = math.random(minp.y, maxp.y)
+		point.z = math.random(minp.z, maxp.z)
+		table.insert(result, point)
+		count = count - 1
+	end
+	
+	math.randomseed(next_seed)
+	return result
+end
+
+-- Returns a random value based on the x and z coordinates of pos, always the same for the same x and z
+mapgen_helper.xz_consistent_randomp = function(pos)
+	local next_seed = math.random(1, 2^21) -- should be 2^31, but I've had a report that this causes a crash in the Lua interpreter on some systems.
+	math.randomseed(pos.x + pos.z * 2 ^ 8)
+	local output = math.random()
+	math.randomseed(next_seed)
+	return output
+end
+
+mapgen_helper.xz_consistent_randomi = function(area, vi)
+	local pos = area:position(vi)
+	return mapgen_helper.xz_consistent_randomp(pos)
+end