musttest_game/mods/utility/functions.lua

-- Localize for performance.
local math_random = math.random
local math_min = math.min
local math_max = math.max

function utility.detach_player_with_message(player)
	local k = default.detach_player_if_attached(player)
	if k then
		local t = player:get_player_name()
		if k == "cart" then
			minetest.chat_send_all("# Server: Someone threw <" .. rename.gpn(t) .. "> out of a minecart.")
		elseif k == "boat" then
			minetest.chat_send_all("# Server: Boater <" .. rename.gpn(t) .. "> was tossed overboard.")
		elseif k == "sled" then
			minetest.chat_send_all("# Server: Someone kicked <" .. rename.gpn(t) .. "> off a sled.")
		elseif k == "bed" then
			minetest.chat_send_all("# Server: <" .. rename.gpn(t) .. "> was rudely kicked out of bed.")
		end
	end
end



-- Function to find an ignore node NOT beyond the world edge.
-- This is useful when we must check for `ignore`, but don't want to be confused at the edge of the world.
function utility.find_node_near_not_world_edge(pos, rad, node)
	local minp = vector.subtract(pos, rad)
	local maxp = vector.add(pos, rad)

	minp.x = math_max(minp.x, -30912)
	minp.y = math_max(minp.y, -30912)
	minp.z = math_max(minp.z, -30912)

	maxp.x = math_min(maxp.x, 30927)
	maxp.y = math_min(maxp.y, 30927)
	maxp.z = math_min(maxp.z, 30927)

	local positions = minetest.find_nodes_in_area(minp, maxp, node)

	if (#positions > 0) then
		return positions[math_random(1, #positions)]
	end
end


local function add_effects(pos, radius)
	minetest.add_particlespawner({
		amount = 8,
		time = 0.5,
		minpos = vector.subtract(pos, radius / 2),
		maxpos = vector.add(pos, radius / 2),
		minvel = {x=-10, y=-10, z=-10},
		maxvel = {x=10,  y=10,  z=10},
		minacc = vector.new(),
		maxacc = vector.new(),
		minexptime = 0.5,
		maxexptime = 1,
		minsize = 0.5,
		maxsize = 1,
		texture = "tnt_smoke.png",
	})
end

function utility.shell_boom(pos)
	minetest.sound_play("throwing_shell_explode", {pos=pos, gain=1.5, max_hear_distance=2*64})

  -- Don't destroy things.
  if minetest.get_node(pos).name == "air" then
    minetest.set_node(pos, {name="tnt:boom"})
    minetest.get_node_timer(pos):start(0.5)
  end

  add_effects(pos, 1)
end



-- Note: this works for boats, too.
-- Returns [""] if player wasn't attached. Otherwise, name of previous attachment type.
function default.detach_player_if_attached(player)
	local pname = player:get_player_name()

	-- Player might be in bed! Get them out properly.
	if beds.kick_one_player(pname) then
		return "bed"
	end

	local ents = minetest.get_objects_inside_radius(utility.get_foot_pos(player:get_pos()), 2)

	local result = ""
	for k, obj in ipairs(ents) do
		local ent = obj:get_luaentity()
		if ent and ent.name == "carts:cart" then
			-- Must detach player from cart.
			carts:manage_attachment(player, nil)
			result = "cart"
		elseif ent and ent.name == "boats:boat" then
			if ent.driver and ent.driver == player then
				-- Since boat driver == player, this should always detach.
				boats.on_rightclick(ent, player)
				result = "boat"
			end
		elseif ent and ent.name == "sleds:sled" then
			if ent.driver and ent.driver == player then
				sleds.on_rightclick(ent, player)
				result = "sled"
			end
		end
	end

	return result
end