lightning/init.lua

228 lines
5.9 KiB
Lua

--[[
Copyright (C) 2016 - Auke Kok <sofar@foo-projects.org>
"lightning" is free software; you can redistribute it and/or modify
it under the terms of the GNU Lesser General Public License as
published by the Free Software Foundation; either version 2.1
of the license, or (at your option) any later version.
--]]
lightning = {}
lightning.interval_low = 17
lightning.interval_high = 503
lightning.range_h = 100
lightning.range_v = 50
lightning.size = 100
-- disable this to stop lightning mod from striking
lightning.auto = true
local rng = PcgRandom(32321123312123)
local ps = {}
local ttl = 1
local revertsky = function()
if ttl == 0 then
return
end
ttl = ttl - 1
if ttl > 0 then
return
end
for key, entry in pairs(ps) do
local sky = entry.sky
entry.p:set_sky(sky.bgcolor, sky.type, sky.textures)
end
ps = {}
end
minetest.register_globalstep(revertsky)
-- select a random strike point, midpoint
local function choose_pos(pos)
if not pos then
local playerlist = minetest.get_connected_players()
local playercount = table.getn(playerlist)
-- nobody on
if playercount == 0 then
return nil, nil
end
local r = rng:next(1, playercount)
local randomplayer = playerlist[r]
pos = randomplayer:getpos()
-- avoid striking underground
if pos.y < -20 then
return nil, nil
end
pos.x = math.floor(pos.x - (lightning.range_h / 2) + rng:next(1, lightning.range_h))
pos.y = pos.y + (lightning.range_v / 2)
pos.z = math.floor(pos.z - (lightning.range_h / 2) + rng:next(1, lightning.range_h))
end
local b, pos2 = minetest.line_of_sight(pos, {x = pos.x, y = pos.y - lightning.range_v, z = pos.z}, 1)
-- nothing but air found
if b then
return nil, nil
end
local n = minetest.get_node({x = pos2.x, y = pos2.y - 1/2, z = pos2.z})
if n.name == "air" or n.name == "ignore" then
return nil, nil
end
return pos, pos2
end
-- lightning strike API
-- * pos: optional, if not given a random pos will be chosen
-- * returns: bool - success if a strike happened
lightning.strike = function(pos)
if lightning.auto then
minetest.after(rng:next(lightning.interval_low, lightning.interval_high), lightning.strike)
end
local pos2
pos, pos2 = choose_pos(pos)
if not pos then
return false
end
minetest.add_particlespawner({
amount = 1,
time = 0.2,
-- make it hit the top of a block exactly with the bottom
minpos = {x = pos2.x, y = pos2.y + (lightning.size / 2) + 1/2, z = pos2.z },
maxpos = {x = pos2.x, y = pos2.y + (lightning.size / 2) + 1/2, z = pos2.z },
minvel = {x = 0, y = 0, z = 0},
maxvel = {x = 0, y = 0, z = 0},
minacc = {x = 0, y = 0, z = 0},
maxacc = {x = 0, y = 0, z = 0},
minexptime = 0.2,
maxexptime = 0.2,
minsize = lightning.size * 10,
maxsize = lightning.size * 10,
collisiondetection = true,
vertical = true,
-- to make it appear hitting the node that will get set on fire, make sure
-- to make the texture lightning bolt hit exactly in the middle of the
-- texture (e.g. 127/128 on a 256x wide texture)
texture = "lightning_lightning_" .. rng:next(1,3) .. ".png",
-- 0.4.15+
glow = 14,
})
minetest.sound_play({ pos = pos, name = "lightning_thunder", gain = 10, max_hear_distance = 500 })
-- damage nearby objects, player or not
for _, obj in ipairs(minetest.get_objects_inside_radius(pos, 5)) do
-- nil as param#1 is supposed to work, but core can't handle it.
obj:punch(obj, 1.0, {full_punch_interval = 1.0, damage_groups = {fleshy=8}}, nil)
end
local playerlist = minetest.get_connected_players()
for i = 1, #playerlist do
local player = playerlist[i]
local sky = {}
sky.bgcolor, sky.type, sky.textures = player:get_sky()
local name = player:get_player_name()
if ps[name] == nil then
ps[name] = {p = player, sky = sky}
player:set_sky(0xffffff, "plain", {})
end
end
-- trigger revert of skybox
ttl = 5
-- set the air node above it on fire
pos2.y = pos2.y + 1/2
if minetest.get_item_group(minetest.get_node({x = pos2.x, y = pos2.y - 1, z = pos2.z}).name, "liquid") < 1 then
if minetest.get_node(pos2).name == "air" then
-- only 1/4 of the time, something is changed
if rng:next(1,4) > 1 then
return
end
-- very rarely, potentially cause a fire
if fire and rng:next(1,1000) == 1 then
minetest.set_node(pos2, {name = "fire:basic_flame"})
else
minetest.set_node(pos2, {name = "lightning:dying_flame"})
end
end
end
-- perform block modifications
if not default or rng:next(1,10) > 1 then
return
end
pos2.y = pos2.y - 1
local n = minetest.get_node(pos2)
if minetest.get_item_group(n.name, "tree") > 0 then
minetest.set_node(pos2, { name = "default:coalblock"})
elseif minetest.get_item_group(n.name, "sand") > 0 then
minetest.set_node(pos2, { name = "default:glass"})
elseif minetest.get_item_group(n.name, "soil") > 0 then
minetest.set_node(pos2, { name = "default:gravel"})
end
end
-- a special fire node that doesn't burn anything, and automatically disappears
minetest.register_node("lightning:dying_flame", {
description = "Dying Flame",
drawtype = "firelike",
tiles = {
{
name = "fire_basic_flame_animated.png",
animation = {
type = "vertical_frames",
aspect_w = 16,
aspect_h = 16,
length = 1
},
},
},
inventory_image = "fire_basic_flame.png",
paramtype = "light",
light_source = 14,
walkable = false,
buildable_to = true,
sunlight_propagates = true,
damage_per_second = 4,
groups = {dig_immediate = 3, not_in_creative_inventory=1},
on_timer = function(pos)
minetest.remove_node(pos)
end,
drop = "",
on_construct = function(pos)
minetest.get_node_timer(pos):start(rng:next(20, 40))
if fire and fire.on_flame_add_at then
minetest.after(0.5, fire.on_flame_add_at, pos)
end
end,
})
-- if other mods disable auto lightning during initialization, don't trigger the first lightning.
minetest.after(5, function(dtime)
if lightning.auto then
minetest.after(rng:next(lightning.interval_low,
lightning.interval_high), lightning.strike)
end
end)
minetest.log("action", "[lightning] loaded.")