update moreblocks, technic, roads, worldedit

4 files changed, 492 insertions, 422 deletions

diff --git a/technic/init.lua b/technic/init.lua
index 70ad848..4464082 100644
--- a/technic/init.lua
+++ b/technic/init.lua
@@ -35,6 +35,9 @@ dofile(modpath.."/crafts.lua")
 -- Register functions
 dofile(modpath.."/register.lua")
 
+-- Radiation
+dofile(modpath.."/radiation.lua")
+
 -- Machines
 dofile(modpath.."/machines/init.lua")
 
diff --git a/technic/items.lua b/technic/items.lua
index 27e05e4..a0edb96 100644
--- a/technic/items.lua
+++ b/technic/items.lua
@@ -194,14 +194,16 @@ for p = 0, 35 do
 	-- a natural (0.7%-fissile) uranium block having the activity of
 	-- 9 uranium ore blocks (due to 9 ingots per block).  The group
 	-- value is proportional to the square root of the activity, and
-	-- uranium ore has radioactive=1000.  This yields radioactive=2065
-	-- for a fully-depleted uranium block and radioactive=5286 for
+	-- uranium ore has radioactive=1.  This yields radioactive=1.0
+	-- for a fully-depleted uranium block and radioactive=2.6 for
 	-- a 3.5%-fissile uranium block.
+	local radioactivity = math.floor(math.sqrt((1+5.55*p/35) * 18 / (1+5.55*7/35)) + 0.5);
 	(ov or minetest.register_node)(block, {
 		description = string.format(S("%.1f%%-Fissile Uranium Block"), p/10),
 		tiles = {"technic_uranium_block.png"},
 		is_ground_content = true,
-		groups = {uranium_block=1, not_in_creative_inventory=nici, cracky=1, level=2, radioactive=math.floor(1000*math.sqrt((1+5.55*p/35) * 9 / (1+5.55*7/35)) + 0.5)},
+		groups = {uranium_block=1, not_in_creative_inventory=nici,
+			cracky=1, level=2, radioactive=radioactivity},
 		sounds = default.node_sound_stone_defaults(),
 	});
 	if not ov then
@@ -219,3 +221,4 @@ for p = 0, 35 do
 		})
 	end
 end
+
diff --git a/technic/machines/HV/nuclear_reactor.lua b/technic/machines/HV/nuclear_reactor.lua
index c7951ab..16bb928 100644
--- a/technic/machines/HV/nuclear_reactor.lua
+++ b/technic/machines/HV/nuclear_reactor.lua
@@ -110,18 +110,17 @@ section through the middle:
 
 	CCCC CCCC
 	CBBB BBBC
-	CBSS SSBC
-	CBSWWWSBC
-	CBSW#WSBC
-	CBSW|WSBC
-	CBSS|SSBC
+	CBLL LLBC
+	CBLWWWLBC
+	CBLW#WLBC
+	CBLW|WLBC
+	CBLL|LLBC
 	CBBB|BBBC
 	CCCC|CCCC
-	C = Concrete, B = Blast-resistant concrete, S = Stainless Steel,
+	C = Concrete, B = Blast-resistant concrete, L = Lead,
 	W = water node, # = reactor core, | = HV cable
 
-The man-hole and the HV cable are only in the middle, and the man-hole
-is optional.
+The man-hole is optional (but necessary for refueling).
 
 For the reactor to operate and not melt down, it insists on the inner
 7x7x7 portion (from the core out to the blast-resistant concrete)
@@ -139,6 +138,9 @@ be mandatory, and for historical reasons (that it predates the
 implementation of radiation) it needs to continue being adequate
 shielding of legacy reactors.  If it ever ceases to be adequate
 shielding for new reactors, legacy ones should be grandfathered.
+
+For legacy reasons, if the reactor has a stainless steel layer instead
+of a lead layer it will be converted to a lead layer.
 --]]
 local function reactor_structure_badness(pos)
 	local vm = VoxelManip()
@@ -149,11 +151,12 @@ local function reactor_structure_badness(pos)
 	local area = VoxelArea:new({MinEdge=MinEdge, MaxEdge=MaxEdge})
 
 	local c_blast_concrete = minetest.get_content_id("technic:blast_resistant_concrete")
-	local c_stainless_steel = minetest.get_content_id("technic:stainless_steel_block")
+	local c_lead = minetest.get_content_id("technic:lead_block")
+	local c_steel = minetest.get_content_id("technic:stainless_steel_block")
 	local c_water_source = minetest.get_content_id("default:water_source")
 	local c_water_flowing = minetest.get_content_id("default:water_flowing")
 
-	local blastlayer, steellayer, waterlayer = 0, 0, 0
+	local blast_layer, steel_layer, lead_layer, water_layer = 0, 0, 0, 0
 
 	for z = pos1.z, pos2.z do
 	for y = pos1.y, pos2.y do
@@ -163,28 +166,51 @@ local function reactor_structure_badness(pos)
 		   y == pos1.y or y == pos2.y or
 		   z == pos1.z or z == pos2.z then
 			if cid == c_blast_concrete then
-				blastlayer = blastlayer + 1
+				blast_layer = blast_layer + 1
 			end
 		elseif x == pos1.x+1 or x == pos2.x-1 or
-		   y == pos1.y+1 or y == pos2.y-1 or
-		   z == pos1.z+1 or z == pos2.z-1 then
-			if cid == c_stainless_steel then
-				steellayer = steellayer + 1
+		       y == pos1.y+1 or y == pos2.y-1 or
+		       z == pos1.z+1 or z == pos2.z-1 then
+			if cid == c_lead then
+				lead_layer = lead_layer + 1
+			elseif cid == c_steel then
+				steel_layer = steel_layer + 1
 			end
 		elseif x == pos1.x+2 or x == pos2.x-2 or
-		   y == pos1.y+2 or y == pos2.y-2 or
-		   z == pos1.z+2 or z == pos2.z-2 then
+		       y == pos1.y+2 or y == pos2.y-2 or
+		       z == pos1.z+2 or z == pos2.z-2 then
 			if cid == c_water_source or cid == c_water_flowing then
-				waterlayer = waterlayer + 1
+				water_layer = water_layer + 1
 			end
 		end
 	end
 	end
 	end
-	if waterlayer > 25 then waterlayer = 25 end
-	if steellayer > 96 then steellayer = 96 end
-	if blastlayer > 216 then blastlayer = 216 end
-	return (25 - waterlayer) + (96 - steellayer) + (216 - blastlayer)
+
+	if steel_layer >= 96 then
+		for z = pos1.z+1, pos2.z-1 do
+		for y = pos1.y+1, pos2.y-1 do
+		for x = pos1.x+1, pos2.x-1 do
+			local vi = area:index(x, y, z)
+			if x == pos1.x+1 or x == pos2.x-1 or
+			   y == pos1.y+1 or y == pos2.y-1 or
+			   z == pos1.z+1 or z == pos2.z-1 then
+				if data[vi] == c_steel then
+					data[vi] = c_lead
+				end
+			end
+		end
+		end
+		end
+		vm:set_data(data)
+		vm:write_to_map()
+		lead_layer = steel_layer
+	end
+
+	if water_layer > 25 then water_layer = 25 end
+	if lead_layer > 96 then lead_layer = 96 end
+	if blast_layer > 216 then blast_layer = 216 end
+	return (25 - water_layer) + (96 - lead_layer) + (216 - blast_layer)
 end
 
 
@@ -292,7 +318,7 @@ minetest.register_node("technic:hv_nuclear_reactor_core", {
 minetest.register_node("technic:hv_nuclear_reactor_core_active", {
 	tiles = {"technic_hv_nuclear_reactor_core.png"},
 	groups = {cracky=1, technic_machine=1, technic_hv=1,
-		radioactive=11000, not_in_creative_inventory=1},
+		radioactive=4, not_in_creative_inventory=1},
 	legacy_facedir_simple = true,
 	sounds = default.node_sound_wood_defaults(),
 	drop = "technic:hv_nuclear_reactor_core",
@@ -339,399 +365,3 @@ minetest.register_node("technic:hv_nuclear_reactor_core_active", {
 technic.register_machine("HV", "technic:hv_nuclear_reactor_core",        technic.producer)
 technic.register_machine("HV", "technic:hv_nuclear_reactor_core_active", technic.producer)
 
---[[
-Radioactivity
-
-Radiation resistance represents the extent to which a material
-attenuates radiation passing through it; i.e., how good a radiation
-shield it is.  This is identified per node type.  For materials that
-exist in real life, the radiation resistance value that this system
-uses for a node type consisting of a solid cube of that material is the
-(approximate) number of halvings of ionising radiation that is achieved
-by a meter of the material in real life.  This is approximately
-proportional to density, which provides a good way to estimate it.
-Homogeneous mixtures of materials have radiation resistance computed
-by a simple weighted mean.  Note that the amount of attenuation that
-a material achieves in-game is not required to be (and is not) the
-same as the attenuation achieved in real life.
-
-Radiation resistance for a node type may be specified in the node
-definition, under the key "radiation_resistance".  As an interim
-measure, until node definitions widely include this, this code
-knows a bunch of values for particular node types in several mods,
-and values for groups of node types.  The node definition takes
-precedence if it specifies a value.  Nodes for which no value at
-all is known are taken to provide no radiation resistance at all;
-this is appropriate for the majority of node types.  Only node types
-consisting of a fairly homogeneous mass of material should report
-non-zero radiation resistance; anything with non-uniform geometry
-or complex internal structure should show no radiation resistance.
-Fractional resistance values are permitted.
---]]
-
-local default_radiation_resistance_per_node = {
-	["default:brick"] = 13,
-	["default:bronzeblock"] = 45,
-	["default:clay"] = 15,
-	["default:coalblock"] = 9.6,
-	["default:cobble"] = 15,
-	["default:copperblock"] = 46,
-	["default:desert_cobble"] = 15,
-	["default:desert_sand"] = 10,
-	["default:desert_stone"] = 17,
-	["default:desert_stonebrick"] = 17,
-	["default:diamondblock"] = 24,
-	["default:dirt"] = 8.2,
-	["default:dirt_with_grass"] = 8.2,
-	["default:dirt_with_grass_footsteps"] = 8.2,
-	["default:dirt_with_snow"] = 8.2,
-	["default:glass"] = 17,
-	["default:goldblock"] = 170,
-	["default:gravel"] = 10,
-	["default:ice"] = 5.6,
-	["default:lava_flowing"] = 8.5,
-	["default:lava_source"] = 17,
-	["default:mese"] = 21,
-	["default:mossycobble"] = 15,
-	["default:nyancat"] = 1000,
-	["default:nyancat_rainbow"] = 1000,
-	["default:obsidian"] = 18,
-	["default:obsidian_glass"] = 18,
-	["default:sand"] = 10,
-	["default:sandstone"] = 15,
-	["default:sandstonebrick"] = 15,
-	["default:snowblock"] = 1.7,
-	["default:steelblock"] = 40,
-	["default:stone"] = 17,
-	["default:stone_with_coal"] = 16,
-	["default:stone_with_copper"] = 20,
-	["default:stone_with_diamond"] = 18,
-	["default:stone_with_gold"] = 34,
-	["default:stone_with_iron"] = 20,
-	["default:stone_with_mese"] = 17,
-	["default:stonebrick"] = 17,
-	["default:water_flowing"] = 2.8,
-	["default:water_source"] = 5.6,
-	["farming:desert_sand_soil"] = 10,
-	["farming:desert_sand_soil_wet"] = 10,
-	["farming:soil"] = 8.2,
-	["farming:soil_wet"] = 8.2,
-	["glooptest:akalin_crystal_glass"] = 21,
-	["glooptest:akalinblock"] = 40,
-	["glooptest:alatro_crystal_glass"] = 21,
-	["glooptest:alatroblock"] = 40,
-	["glooptest:amethystblock"] = 18,
-	["glooptest:arol_crystal_glass"] = 21,
-	["glooptest:crystal_glass"] = 21,
-	["glooptest:emeraldblock"] = 19,
-	["glooptest:heavy_crystal_glass"] = 21,
-	["glooptest:mineral_akalin"] = 20,
-	["glooptest:mineral_alatro"] = 20,
-	["glooptest:mineral_amethyst"] = 17,
-	["glooptest:mineral_arol"] = 20,
-	["glooptest:mineral_desert_coal"] = 16,
-	["glooptest:mineral_desert_iron"] = 20,
-	["glooptest:mineral_emerald"] = 17,
-	["glooptest:mineral_kalite"] = 20,
-	["glooptest:mineral_ruby"] = 18,
-	["glooptest:mineral_sapphire"] = 18,
-	["glooptest:mineral_talinite"] = 20,
-	["glooptest:mineral_topaz"] = 18,
-	["glooptest:reinforced_crystal_glass"] = 21,
-	["glooptest:rubyblock"] = 27,
-	["glooptest:sapphireblock"] = 27,
-	["glooptest:talinite_crystal_glass"] = 21,
-	["glooptest:taliniteblock"] = 40,
-	["glooptest:topazblock"] = 24,
-	["mesecons_extrawires:mese_powered"] = 21,
-	["moreblocks:cactus_brick"] = 13,
-	["moreblocks:cactus_checker"] = 8.5,
-	["moreblocks:circle_stone_bricks"] = 17,
-	["moreblocks:clean_glass"] = 17,
-	["moreblocks:coal_checker"] = 9.0,
-	["moreblocks:coal_glass"] = 17,
-	["moreblocks:coal_stone"] = 17,
-	["moreblocks:coal_stone_bricks"] = 17,
-	["moreblocks:glow_glass"] = 17,
-	["moreblocks:grey_bricks"] = 15,
-	["moreblocks:iron_checker"] = 11,
-	["moreblocks:iron_glass"] = 17,
-	["moreblocks:iron_stone"] = 17,
-	["moreblocks:iron_stone_bricks"] = 17,
-	["moreblocks:plankstone"] = 9.3,
-	["moreblocks:split_stone_tile"] = 15,
-	["moreblocks:split_stone_tile_alt"] = 15,
-	["moreblocks:stone_tile"] = 15,
-	["moreblocks:super_glow_glass"] = 17,
-	["moreblocks:tar"] = 7.0,
-	["moreblocks:wood_tile"] = 1.7,
-	["moreblocks:wood_tile_center"] = 1.7,
-	["moreblocks:wood_tile_down"] = 1.7,
-	["moreblocks:wood_tile_flipped"] = 1.7,
-	["moreblocks:wood_tile_full"] = 1.7,
-	["moreblocks:wood_tile_left"] = 1.7,
-	["moreblocks:wood_tile_right"] = 1.7,
-	["moreblocks:wood_tile_up"] = 1.7,
-	["moreores:mineral_mithril"] = 18,
-	["moreores:mineral_silver"] = 21,
-	["moreores:mineral_tin"] = 19,
-	["moreores:mithril_block"] = 26,
-	["moreores:silver_block"] = 53,
-	["moreores:tin_block"] = 37,
-	["snow:snow_brick"] = 2.8,
-	["technic:brass_block"] = 43,
-	["technic:carbon_steel_block"] = 40,
-	["technic:cast_iron_block"] = 40,
-	["technic:chernobylite_block"] = 40,
-	["technic:chromium_block"] = 37,
-	["technic:corium_flowing"] = 40,
-	["technic:corium_source"] = 80,
-	["technic:granite"] = 18,
-	["technic:lead_block"] = 80,
-	["technic:marble"] = 18,
-	["technic:marble_bricks"] = 18,
-	["technic:mineral_chromium"] = 19,
-	["technic:mineral_uranium"] = 71,
-	["technic:mineral_zinc"] = 19,
-	["technic:stainless_steel_block"] = 40,
-	["technic:zinc_block"] = 36,
-	["tnt:tnt"] = 11,
-	["tnt:tnt_burning"] = 11,
-}
-local default_radiation_resistance_per_group = {
-	concrete = 16,
-	tree = 3.4,
-	uranium_block = 500,
-	wood = 1.7,
-}
-local cache_radiation_resistance = {}
-local function node_radiation_resistance(node_name)
-	local eff = cache_radiation_resistance[node_name]
-	if eff then return eff end
-	local def = minetest.registered_nodes[node_name]
-	eff = def and def.radiation_resistance or
-			default_radiation_resistance_per_node[node_name]
-	if def and not eff then
-		for g, v in pairs(def.groups) do
-			if v > 0 and default_radiation_resistance_per_group[g] then
-				eff = default_radiation_resistance_per_group[g]
-				break
-			end
-		end
-	end
-	if not eff then eff = 0 end
-	cache_radiation_resistance[node_name] = eff
-	return eff
-end
-
---[[
-Radioactive nodes cause damage to nearby players.  The damage
-effect depends on the intrinsic strength of the radiation source,
-the distance between the source and the player, and the shielding
-effect of the intervening material.  These determine a rate of damage;
-total damage caused is the integral of this over time.
-
-In the absence of effective shielding, for a specific source the
-damage rate varies realistically in inverse proportion to the square
-of the distance.  (Distance is measured to the player's abdomen,
-not to the nominal player position which corresponds to the foot.)
-However, if the player is inside a non-walkable (liquid or gaseous)
-radioactive node, the nominal distance could go to zero, yielding
-infinite damage.  In that case, the player's body is displacing the
-radioactive material, so the effective distance should remain non-zero.
-We therefore apply a lower distance bound of sqrt(0.75), which is
-the maximum distance one can get from the node center within the node.
-
-A radioactive node is identified by being in the "radioactive" group,
-and the group value signifies the strength of the radiation source.
-The group value is 1000 times the distance from a node at which
-an unshielded player will be damaged by 0.25 HP/s.  Or, equivalently,
-it is 2000 times the square root of the damage rate in HP/s that an
-unshielded player 1 node away will take.
-
-Shielding is assessed by adding the shielding values of all nodes
-between the source node and the player, ignoring the source node itself.
-As in reality, shielding causes exponential attenuation of radiation.
-However, the effect is scaled down relative to real life.  A node with
-radiation resistance value R yields attenuation of sqrt(R) * 0.1 nepers.
-(In real life it would be about R * 0.69 nepers, by the definition
-of the radiation resistance values.)  The sqrt part of this formula
-scales down the differences between shielding types, reflecting the
-game's simplification of making expensive materials such as gold
-readily available in cubes.  The multiplicative factor in the
-formula scales down the difference between shielded and unshielded
-safe distances, avoiding the latter becoming impractically large.
-
-Damage is processed at rates down to 0.25 HP/s, which in the absence of
-shielding is attained at the distance specified by the "radioactive"
-group value.  Computed damage rates below 0.25 HP/s result in no
-damage at all to the player.  This gives the player an opportunity
-to be safe, and limits the range at which source/player interactions
-need to be considered.
---]]
-local abdomen_offset = vector.new(0, 1, 0)
-local abdomen_offset_length = vector.length(abdomen_offset)
-local cache_scaled_shielding = {}
-
-local function dmg_player(pos, o, strength)
-	local pl_pos = vector.add(o:getpos(), abdomen_offset)
-	local shielding = 0
-	local dist = vector.distance(pos, pl_pos)
-	for ray_pos in technic.trace_node_ray(pos,
-			vector.direction(pos, pl_pos), dist) do
-		if not vector.equals(ray_pos, pos) then
-			local shield_name = minetest.get_node(ray_pos).name
-			local shield_val = cache_scaled_shielding[sname]
-			if not shield_val then
-				shield_val = math.sqrt(node_radiation_resistance(shield_name)) * 0.025
-				cache_scaled_shielding[shield_name] = shield_val
-			end
-			shielding = shielding + shield_val
-		end
-	end
-	local dmg = (0.25e-6 * strength * strength) /
-		(math.max(0.75, dist * dist) * math.exp(shielding))
-	if dmg >= 0.25 then
-		local dmg_int = math.floor(dmg)
-		-- The closer you are to getting one more damage point,
-		-- the more likely it will be added.
-		if math.random() < dmg - dmg_int then
-			dmg_int = dmg_int + 1
-		end
-		if dmg_int > 0 then
-			o:set_hp(math.max(o:get_hp() - dmg_int, 0))
-		end
-	end
-end
-
-local function dmg_abm(pos, node)
-	local strength = minetest.get_item_group(node.name, "radioactive")
-	for _, o in pairs(minetest.get_objects_inside_radius(pos,
-			strength * 0.001 + abdomen_offset_length)) do
-		if o:is_player() then
-			dmg_player(pos, o, strength)
-		end
-	end
-end
-
-
-if minetest.setting_getbool("enable_damage") then
-	minetest.register_abm({
-		nodenames = {"group:radioactive"},
-		interval = 1,
-		chance = 1,
-		action = dmg_abm,
-	})
-end
-
--- Radioactive materials that can result from destroying a reactor
-local griefing = technic.config:get_bool("enable_corium_griefing")
-
-for _, state in pairs({"flowing", "source"}) do
-	minetest.register_node("technic:corium_"..state, {
-		description = S(state == "source" and "Corium Source" or "Flowing Corium"),
-		drawtype = (state == "source" and "liquid" or "flowingliquid"),
-		[state == "source" and "tiles" or "special_tiles"] = {{
-			name = "technic_corium_"..state.."_animated.png",
-			animation = {
-				type = "vertical_frames",
-				aspect_w = 16,
-				aspect_h = 16,
-				length = 3.0,
-			},
-		}},
-		paramtype = "light",
-		paramtype2 = (state == "flowing" and "flowingliquid" or nil),
-		light_source = (state == "source" and 8 or 5),
-		walkable = false,
-		pointable = false,
-		diggable = false,
-		buildable_to = true,
-		drop = "",
-		drowning = 1,
-		liquidtype = state,
-		liquid_alternative_flowing = "technic:corium_flowing",
-		liquid_alternative_source = "technic:corium_source",
-		liquid_viscosity = LAVA_VISC,
-		liquid_renewable = false,
-		damage_per_second = 6,
-		post_effect_color = {a=192, r=80, g=160, b=80},
-		groups = {
-			liquid = 2,
-			hot = 3,
-			igniter = (griefing and 1 or 0),
-			radioactive = (state == "source" and 32000 or 16000),
-			not_in_creative_inventory = (state == "flowing" and 1 or nil),
-		},
-	})
-end
-
-if rawget(_G, "bucket") and bucket.register_liquid then
-	bucket.register_liquid(
-		"technic:corium_source",
-		"technic:corium_flowing",
-		"technic:bucket_corium",
-		"technic_bucket_corium.png",
-		"Corium Bucket"
-	)
-end
-
-minetest.register_node("technic:chernobylite_block", {
-        description = S("Chernobylite Block"),
-	tiles = {"technic_chernobylite_block.png"},
-	is_ground_content = true,
-	groups = {cracky=1, radioactive=5000, level=2},
-	sounds = default.node_sound_stone_defaults(),
-	light_source = 2,
-})
-
-minetest.register_abm({
-	nodenames = {"group:water"},
-	neighbors = {"technic:corium_source"},
-	interval = 1,
-	chance = 1,
-	action = function(pos, node)
-		minetest.remove_node(pos)
-	end,
-})
-
-minetest.register_abm({
-	nodenames = {"technic:corium_flowing"},
-	neighbors = {"group:water"},
-	interval = 1,
-	chance = 1,
-	action = function(pos, node)
-		minetest.set_node(pos, {name="technic:chernobylite_block"})
-	end,
-})
-
-minetest.register_abm({
-	nodenames = {"technic:corium_flowing"},
-	interval = 5,
-	chance = (griefing and 10 or 1),
-	action = function(pos, node)
-		minetest.set_node(pos, {name="technic:chernobylite_block"})
-	end,
-})
-
-if griefing then
-	minetest.register_abm({
-		nodenames = {"technic:corium_source", "technic:corium_flowing"},
-		interval = 4,
-		chance = 4,
-		action = function(pos, node)
-			for _, offset in ipairs({
-				vector.new(1,0,0),
-				vector.new(-1,0,0),
-				vector.new(0,0,1),
-				vector.new(0,0,-1),
-				vector.new(0,-1,0),
-			}) do
-				if math.random(8) == 1 then
-					minetest.dig_node(vector.add(pos, offset))
-				end
-			end
-		end,
-	})
-end
-
diff --git a/technic/radiation.lua b/technic/radiation.lua
new file mode 100644
index 0000000..ac3f166
--- /dev/null
+++ b/technic/radiation.lua
@@ -0,0 +1,434 @@
+--[[
+Radioactivity
+
+Radiation resistance represents the extent to which a material
+attenuates radiation passing through it; i.e., how good a radiation
+shield it is.  This is identified per node type.  For materials that
+exist in real life, the radiation resistance value that this system
+uses for a node type consisting of a solid cube of that material is the
+(approximate) number of halvings of ionising radiation that is achieved
+by a meter of the material in real life.  This is approximately
+proportional to density, which provides a good way to estimate it.
+Homogeneous mixtures of materials have radiation resistance computed
+by a simple weighted mean.  Note that the amount of attenuation that
+a material achieves in-game is not required to be (and is not) the
+same as the attenuation achieved in real life.
+
+Radiation resistance for a node type may be specified in the node
+definition, under the key "radiation_resistance".  As an interim
+measure, until node definitions widely include this, this code
+knows a bunch of values for particular node types in several mods,
+and values for groups of node types.  The node definition takes
+precedence if it specifies a value.  Nodes for which no value at
+all is known are taken to provide no radiation resistance at all;
+this is appropriate for the majority of node types.  Only node types
+consisting of a fairly homogeneous mass of material should report
+non-zero radiation resistance; anything with non-uniform geometry
+or complex internal structure should show no radiation resistance.
+Fractional resistance values are permitted.
+--]]
+
+local S = technic.getter
+
+local rad_resistance_node = {
+	["default:brick"] = 13,
+	["default:bronzeblock"] = 45,
+	["default:clay"] = 15,
+	["default:coalblock"] = 9.6,
+	["default:cobble"] = 15,
+	["default:copperblock"] = 46,
+	["default:desert_cobble"] = 15,
+	["default:desert_sand"] = 10,
+	["default:desert_stone"] = 17,
+	["default:desert_stonebrick"] = 17,
+	["default:diamondblock"] = 24,
+	["default:dirt"] = 8.2,
+	["default:dirt_with_grass"] = 8.2,
+	["default:dirt_with_grass_footsteps"] = 8.2,
+	["default:dirt_with_snow"] = 8.2,
+	["default:glass"] = 17,
+	["default:goldblock"] = 170,
+	["default:gravel"] = 10,
+	["default:ice"] = 5.6,
+	["default:lava_flowing"] = 8.5,
+	["default:lava_source"] = 17,
+	["default:mese"] = 21,
+	["default:mossycobble"] = 15,
+	["default:nyancat"] = 1000,
+	["default:nyancat_rainbow"] = 1000,
+	["default:obsidian"] = 18,
+	["default:obsidian_glass"] = 18,
+	["default:sand"] = 10,
+	["default:sandstone"] = 15,
+	["default:sandstonebrick"] = 15,
+	["default:snowblock"] = 1.7,
+	["default:steelblock"] = 40,
+	["default:stone"] = 17,
+	["default:stone_with_coal"] = 16,
+	["default:stone_with_copper"] = 20,
+	["default:stone_with_diamond"] = 18,
+	["default:stone_with_gold"] = 34,
+	["default:stone_with_iron"] = 20,
+	["default:stone_with_mese"] = 17,
+	["default:stonebrick"] = 17,
+	["default:water_flowing"] = 2.8,
+	["default:water_source"] = 5.6,
+	["farming:desert_sand_soil"] = 10,
+	["farming:desert_sand_soil_wet"] = 10,
+	["farming:soil"] = 8.2,
+	["farming:soil_wet"] = 8.2,
+	["glooptest:akalin_crystal_glass"] = 21,
+	["glooptest:akalinblock"] = 40,
+	["glooptest:alatro_crystal_glass"] = 21,
+	["glooptest:alatroblock"] = 40,
+	["glooptest:amethystblock"] = 18,
+	["glooptest:arol_crystal_glass"] = 21,
+	["glooptest:crystal_glass"] = 21,
+	["glooptest:emeraldblock"] = 19,
+	["glooptest:heavy_crystal_glass"] = 21,
+	["glooptest:mineral_akalin"] = 20,
+	["glooptest:mineral_alatro"] = 20,
+	["glooptest:mineral_amethyst"] = 17,
+	["glooptest:mineral_arol"] = 20,
+	["glooptest:mineral_desert_coal"] = 16,
+	["glooptest:mineral_desert_iron"] = 20,
+	["glooptest:mineral_emerald"] = 17,
+	["glooptest:mineral_kalite"] = 20,
+	["glooptest:mineral_ruby"] = 18,
+	["glooptest:mineral_sapphire"] = 18,
+	["glooptest:mineral_talinite"] = 20,
+	["glooptest:mineral_topaz"] = 18,
+	["glooptest:reinforced_crystal_glass"] = 21,
+	["glooptest:rubyblock"] = 27,
+	["glooptest:sapphireblock"] = 27,
+	["glooptest:talinite_crystal_glass"] = 21,
+	["glooptest:taliniteblock"] = 40,
+	["glooptest:topazblock"] = 24,
+	["mesecons_extrawires:mese_powered"] = 21,
+	["moreblocks:cactus_brick"] = 13,
+	["moreblocks:cactus_checker"] = 8.5,
+	["moreblocks:circle_stone_bricks"] = 17,
+	["moreblocks:clean_glass"] = 17,
+	["moreblocks:coal_checker"] = 9.0,
+	["moreblocks:coal_glass"] = 17,
+	["moreblocks:coal_stone"] = 17,
+	["moreblocks:coal_stone_bricks"] = 17,
+	["moreblocks:glow_glass"] = 17,
+	["moreblocks:grey_bricks"] = 15,
+	["moreblocks:iron_checker"] = 11,
+	["moreblocks:iron_glass"] = 17,
+	["moreblocks:iron_stone"] = 17,
+	["moreblocks:iron_stone_bricks"] = 17,
+	["moreblocks:plankstone"] = 9.3,
+	["moreblocks:split_stone_tile"] = 15,
+	["moreblocks:split_stone_tile_alt"] = 15,
+	["moreblocks:stone_tile"] = 15,
+	["moreblocks:super_glow_glass"] = 17,
+	["moreblocks:tar"] = 7.0,
+	["moreblocks:wood_tile"] = 1.7,
+	["moreblocks:wood_tile_center"] = 1.7,
+	["moreblocks:wood_tile_down"] = 1.7,
+	["moreblocks:wood_tile_flipped"] = 1.7,
+	["moreblocks:wood_tile_full"] = 1.7,
+	["moreblocks:wood_tile_left"] = 1.7,
+	["moreblocks:wood_tile_right"] = 1.7,
+	["moreblocks:wood_tile_up"] = 1.7,
+	["moreores:mineral_mithril"] = 18,
+	["moreores:mineral_silver"] = 21,
+	["moreores:mineral_tin"] = 19,
+	["moreores:mithril_block"] = 26,
+	["moreores:silver_block"] = 53,
+	["moreores:tin_block"] = 37,
+	["snow:snow_brick"] = 2.8,
+	["technic:brass_block"] = 43,
+	["technic:carbon_steel_block"] = 40,
+	["technic:cast_iron_block"] = 40,
+	["technic:chernobylite_block"] = 40,
+	["technic:chromium_block"] = 37,
+	["technic:corium_flowing"] = 40,
+	["technic:corium_source"] = 80,
+	["technic:granite"] = 18,
+	["technic:lead_block"] = 80,
+	["technic:marble"] = 18,
+	["technic:marble_bricks"] = 18,
+	["technic:mineral_chromium"] = 19,
+	["technic:mineral_uranium"] = 71,
+	["technic:mineral_zinc"] = 19,
+	["technic:stainless_steel_block"] = 40,
+	["technic:zinc_block"] = 36,
+	["tnt:tnt"] = 11,
+	["tnt:tnt_burning"] = 11,
+}
+local rad_resistance_group = {
+	concrete = 16,
+	tree = 3.4,
+	uranium_block = 500,
+	wood = 1.7,
+}
+local cache_radiation_resistance = {}
+local function node_radiation_resistance(node_name)
+	local resistance = cache_radiation_resistance[node_name]
+	if resistance then
+		return resistance
+	end
+	local def = minetest.registered_nodes[node_name]
+	if not def then
+		cache_radiation_resistance[node_name] = 0
+		return 0
+	end
+	resistance = def.radiation_resistance or
+			rad_resistance_node[node_name]
+	if not resistance then
+		resistance = 0
+		for g, v in pairs(def.groups) do
+			if v > 0 and rad_resistance_group[g] then
+				resistance = resistance + rad_resistance_group[g]
+			end
+		end
+	end
+	resistance = math.sqrt(resistance)
+	cache_radiation_resistance[node_name] = resistance
+	return resistance
+end
+
+
+--[[
+Radioactive nodes cause damage to nearby players.  The damage
+effect depends on the intrinsic strength of the radiation source,
+the distance between the source and the player, and the shielding
+effect of the intervening material.  These determine a rate of damage;
+total damage caused is the integral of this over time.
+
+In the absence of effective shielding, for a specific source the
+damage rate varies realistically in inverse proportion to the square
+of the distance.  (Distance is measured to the player's abdomen,
+not to the nominal player position which corresponds to the foot.)
+However, if the player is inside a non-walkable (liquid or gaseous)
+radioactive node, the nominal distance could go to zero, yielding
+infinite damage.  In that case, the player's body is displacing the
+radioactive material, so the effective distance should remain non-zero.
+We therefore apply a lower distance bound of sqrt(0.75), which is
+the maximum distance one can get from the node center within the node.
+
+A radioactive node is identified by being in the "radioactive" group,
+and the group value signifies the strength of the radiation source.
+The group value is the distance from a node at which an unshielded
+player will be damaged by 1 HP/s.  Or, equivalently, it is the square
+root of the damage rate in HP/s that an unshielded player one node
+away will take.
+
+Shielding is assessed by adding the shielding values of all nodes
+between the source node and the player, ignoring the source node itself.
+As in reality, shielding causes exponential attenuation of radiation.
+However, the effect is scaled down relative to real life.  A node with
+radiation resistance value R yields attenuation of sqrt(R) * 0.1 nepers.
+(In real life it would be about R * 0.69 nepers, by the definition
+of the radiation resistance values.)  The sqrt part of this formula
+scales down the differences between shielding types, reflecting the
+game's simplification of making expensive materials such as gold
+readily available in cubes.  The multiplicative factor in the
+formula scales down the difference between shielded and unshielded
+safe distances, avoiding the latter becoming impractically large.
+
+Damage is processed at rates down to 0.2 HP/s, which in the absence of
+shielding is attained at the distance specified by the "radioactive"
+group value.  Computed damage rates below 0.2 HP/s result in no
+damage at all to the player.  This gives the player an opportunity
+to be safe, and limits the range at which source/player interactions
+need to be considered.
+--]]
+local abdomen_offset = 1
+local cache_scaled_shielding = {}
+local rad_dmg_cutoff = 0.2
+local radiated_players = {}
+
+local function apply_fractional_damage(o, dmg)
+	local dmg_int = math.floor(dmg)
+	-- The closer you are to getting one more damage point,
+	-- the more likely it will be added.
+	if math.random() < dmg - dmg_int then
+		dmg_int = dmg_int + 1
+	end
+	if dmg_int > 0 then
+		local new_hp = math.max(o:get_hp() - dmg_int, 0)
+		o:set_hp(new_hp)
+		return new_hp == 0
+	end
+	return false
+end
+
+local function dmg_player(pos, player, strength)
+	local pl_pos = player:getpos()
+	pl_pos.y = pl_pos.y + abdomen_offset
+	local shielding = 0
+	local dist = vector.distance(pos, pl_pos)
+
+	for ray_pos in technic.trace_node_ray(pos,
+			vector.direction(pos, pl_pos), dist) do
+		local shield_name = minetest.get_node(ray_pos).name
+		shielding = shielding + node_radiation_resistance(shield_name) * 0.1
+	end
+
+	local dmg = (strength * strength) /
+		(math.max(0.75, dist * dist) * math.exp(shielding))
+
+	if dmg < rad_dmg_cutoff then return end
+	apply_fractional_damage(player, dmg)
+
+	local pn = player:get_player_name()
+	radiated_players[pn] = (radiated_players[pn] or 0) + dmg
+end
+
+local rad_dmg_mult_sqrt = math.sqrt(1 / rad_dmg_cutoff)
+local function dmg_abm(pos, node)
+	local strength = minetest.get_item_group(node.name, "radioactive")
+	local max_dist = strength * rad_dmg_mult_sqrt
+	for _, o in pairs(minetest.get_objects_inside_radius(pos,
+			max_dist + abdomen_offset)) do
+		if o:is_player() then
+			dmg_player(pos, o, strength)
+		end
+	end
+end
+
+if minetest.setting_getbool("enable_damage") then
+	minetest.register_abm({
+		nodenames = {"group:radioactive"},
+		interval = 1,
+		chance = 1,
+		action = dmg_abm,
+	})
+
+	minetest.register_globalstep(function(dtime)
+		for pn, dmg in pairs(radiated_players) do
+			dmg = dmg - (dtime / 8)
+			local player = minetest.get_player_by_name(pn)
+			local killed
+			if player and dmg > rad_dmg_cutoff then
+				killed = apply_fractional_damage(player, (dmg * dtime) / 8)
+			else
+				dmg = nil
+			end
+			-- on_dieplayer will have already set this if the player died
+			if not killed then
+				radiated_players[pn] = dmg
+			end
+		end
+	end)
+
+	minetest.register_on_dieplayer(function(player)
+		radiated_players[player:get_player_name()] = nil
+	end)
+end
+
+-- Radioactive materials that can result from destroying a reactor
+local griefing = technic.config:get_bool("enable_corium_griefing")
+
+for _, state in pairs({"flowing", "source"}) do
+	minetest.register_node("technic:corium_"..state, {
+		description = S(state == "source" and "Corium Source" or "Flowing Corium"),
+		drawtype = (state == "source" and "liquid" or "flowingliquid"),
+		[state == "source" and "tiles" or "special_tiles"] = {{
+			name = "technic_corium_"..state.."_animated.png",
+			animation = {
+				type = "vertical_frames",
+				aspect_w = 16,
+				aspect_h = 16,
+				length = 3.0,
+			},
+		}},
+		paramtype = "light",
+		paramtype2 = (state == "flowing" and "flowingliquid" or nil),
+		light_source = (state == "source" and 8 or 5),
+		walkable = false,
+		pointable = false,
+		diggable = false,
+		buildable_to = true,
+		drop = "",
+		drowning = 1,
+		liquidtype = state,
+		liquid_alternative_flowing = "technic:corium_flowing",
+		liquid_alternative_source = "technic:corium_source",
+		liquid_viscosity = LAVA_VISC,
+		liquid_renewable = false,
+		damage_per_second = 6,
+		post_effect_color = {a=192, r=80, g=160, b=80},
+		groups = {
+			liquid = 2,
+			hot = 3,
+			igniter = (griefing and 1 or 0),
+			radioactive = (state == "source" and 12 or 6),
+			not_in_creative_inventory = (state == "flowing" and 1 or nil),
+		},
+	})
+end
+
+if rawget(_G, "bucket") and bucket.register_liquid then
+	bucket.register_liquid(
+		"technic:corium_source",
+		"technic:corium_flowing",
+		"technic:bucket_corium",
+		"technic_bucket_corium.png",
+		"Corium Bucket"
+	)
+end
+
+minetest.register_node("technic:chernobylite_block", {
+        description = S("Chernobylite Block"),
+	tiles = {"technic_chernobylite_block.png"},
+	is_ground_content = true,
+	groups = {cracky=1, radioactive=4, level=2},
+	sounds = default.node_sound_stone_defaults(),
+	light_source = 2,
+})
+
+minetest.register_abm({
+	nodenames = {"group:water"},
+	neighbors = {"technic:corium_source"},
+	interval = 1,
+	chance = 1,
+	action = function(pos, node)
+		minetest.remove_node(pos)
+	end,
+})
+
+minetest.register_abm({
+	nodenames = {"technic:corium_flowing"},
+	neighbors = {"group:water"},
+	interval = 1,
+	chance = 1,
+	action = function(pos, node)
+		minetest.set_node(pos, {name="technic:chernobylite_block"})
+	end,
+})
+
+minetest.register_abm({
+	nodenames = {"technic:corium_flowing"},
+	interval = 5,
+	chance = (griefing and 10 or 1),
+	action = function(pos, node)
+		minetest.set_node(pos, {name="technic:chernobylite_block"})
+	end,
+})
+
+if griefing then
+	minetest.register_abm({
+		nodenames = {"technic:corium_source", "technic:corium_flowing"},
+		interval = 4,
+		chance = 4,
+		action = function(pos, node)
+			for _, offset in ipairs({
+				vector.new(1,0,0),
+				vector.new(-1,0,0),
+				vector.new(0,0,1),
+				vector.new(0,0,-1),
+				vector.new(0,-1,0),
+			}) do
+				if math.random(8) == 1 then
+					minetest.dig_node(vector.add(pos, offset))
+				end
+			end
+		end,
+	})
+end
+