From 186abc20f3e58d137949ad462526744a95e564be Mon Sep 17 00:00:00 2001
From: Duane <duane@duanerobertson.com>
Date: Sat, 9 Jul 2016 04:45:09 -0500
Subject: [PATCH] Add flatten command.

---
 chat.lua      | 118 ++++++++++++++++++++++++++++++++++++++++++++++++++
 spec_bomb.lua |   4 +-
 2 files changed, 120 insertions(+), 2 deletions(-)

diff --git a/chat.lua b/chat.lua
index 6a4b7ad..79789e5 100644
--- a/chat.lua
+++ b/chat.lua
@@ -60,3 +60,121 @@ minetest.register_chatcommand("fixlight", {
 		vm:update_map()
 	end,
 })
+
+
+minetest.register_chatcommand("flatten", {
+	params = "<radius>",
+	description = "flatten terrain",
+	privs = {},
+	func = function(name, param)
+		local privs = minetest.check_player_privs(name, {server=true})
+		if not privs then
+			return
+		end
+
+		print('Fun Caves: '..name..' used the flatten command')
+		local player = minetest.get_player_by_name(name)
+		local pos = vector.round(player:getpos())
+		local radius = tonumber(param) or 50
+		radius = math.floor(radius)
+		local minp = vector.subtract(pos, radius)
+		minp.y = minp.y - math.ceil(radius / 2)
+		local maxp = vector.add(pos, radius)
+		maxp.y = maxp.y + math.ceil(radius / 2)
+		local air = minetest.get_content_id('air')
+		local stone = minetest.get_content_id('default:stone')
+		local water = minetest.get_content_id('default:water_source')
+		local waters = {}
+		waters[minetest.get_content_id('default:water_source')] = true
+		waters[minetest.get_content_id('default:river_water_source')] = true
+		local stone_types = {'default:stone', 'default:desert_stone', 'default:sandstone', 'default:dirt', 'fun_caves:dirt', 'default:dirt_with_snow', 'default:dirt_with_grass', 'default:dirt_with_dry_grass', 'default:sand', 'default:desert_sand'}
+		local stones = {}
+		for i = 1, #stone_types do
+			stones[minetest.get_content_id(stone_types[i])] = true
+		end
+
+		local vm = minetest.get_voxel_manip(minp, maxp)
+		local emin, emax = vm:read_from_map(minp, maxp)
+		local area = VoxelArea:new({MinEdge = emin, MaxEdge = emax})
+		local data = vm:get_data()
+		local heightmap = {}
+		local height_avg = 0
+		local count = 0
+		local index = 1
+		for z = minp.z, maxp.z do
+			for x = minp.x, maxp.x do
+				local ivm = area:index(x, maxp.y, z)
+				for y = maxp.y, minp.y, -1 do
+					if stones[data[ivm]] then
+						if y >= maxp.y then
+							print('Terrain altitude exceeds the radius.')
+							return
+						end
+						heightmap[index] = y
+						height_avg = height_avg + heightmap[index]
+						count = count + 1
+						break
+					end
+					ivm = ivm - area.ystride
+				end
+
+				if not heightmap[index] then
+					print('Terrain altitude exceeds the radius.')
+					return
+				end
+
+				index = index + 1
+			end
+		end
+		height_avg = math.floor(height_avg / count + 0.5)
+
+		index = 1
+		for z = minp.z, maxp.z do
+			local dz = z - minp.z
+			for x = minp.x, maxp.x do
+				local dx = x - minp.x
+				local r = math.max(math.abs(radius - dx), math.abs(radius - dz)) / radius
+				local new_y = heightmap[index]
+				if r < 1 then
+					new_y = math.floor(heightmap[index] * r ^ 2 + height_avg * (1 - r ^ 2) + 0.5)
+				end
+				local delta = new_y - heightmap[index]
+				if delta > 0 then
+					local ivm = area:index(x, maxp.y, z)
+					for y = maxp.y - delta, new_y, -1 do
+						data[ivm] = data[ivm - area.ystride * delta]
+						ivm = ivm - area.ystride
+					end
+				elseif delta < 0 then
+					local ivm = area:index(x, new_y - 2, z)
+					for y = new_y - 2, maxp.y + delta do
+						data[ivm] = data[ivm - area.ystride * delta]
+						ivm = ivm + area.ystride
+					end
+					for y = maxp.y + delta + 1, maxp.y do
+						data[ivm] = air
+						ivm = ivm + area.ystride
+					end
+				end
+
+				local ivm = area:index(x, minp.y, z)
+				for y = minp.y, maxp.y do
+					if y <= 1 and data[ivm] == air then
+						data[ivm] = water
+					elseif y > 1 and waters[data[ivm]] then
+						data[ivm] = air
+					end
+					ivm = ivm + area.ystride
+				end
+
+				index = index + 1
+			end
+		end
+
+		vm:set_data(data)
+		vm:calc_lighting(minp, maxp)
+		vm:update_liquids()
+		vm:write_to_map()
+		vm:update_map()
+	end,
+})
diff --git a/spec_bomb.lua b/spec_bomb.lua
index 7845bb2..967c185 100644
--- a/spec_bomb.lua
+++ b/spec_bomb.lua
@@ -73,7 +73,7 @@ end
 
 
 -- Bombs
-local nodes = {{'fun_caves:pyramid_1', 'default:sandstone'}, {'fun_caves:tree', 'fun_caves:tree'},}
+local nodes = {{'fun_caves:pyramid_1', 'default:sandstone'}, {'fun_caves:tree', 'fun_caves:tree'}, {'default:stone', 'default:cobble'},}
 for _, node in pairs(nodes) do
 	local node_name = node[1]
 	local comp = node[2] or node_name
@@ -106,7 +106,7 @@ end
 
 
 -- Floor bombs
-local nodes = {{'default:sandstone', 'default:sandstone_block'}, {'default:wood', 'fun_caves:wood_block'},}
+local nodes = {{'default:sandstone', 'default:sandstone_block'}, {'default:wood', 'fun_caves:wood_block'}, {'default:stone', 'default:stone_block'},}
 for _, node in pairs(nodes) do
 	local node_name = node[1]
 	local comp = node[2] or node_name