server-nalc/mods/item_drop/init.lua

item_drop = {}
local enable_damage = minetest.setting_getbool("enable_damage")
local creative_mode = minetest.setting_getbool("creative_mode")
local TICK_UPDATE = 0.1


local die_timeout = 20
local die_time = {}
local die_respawned = {}

minetest.register_on_joinplayer(function(player)
	local player_name = player:get_player_name()
	die_time[player_name] = 0
	die_respawned[player_name] = false
end)

minetest.register_on_leaveplayer(function(player)
	local player_name = player:get_player_name()
	die_time[player_name] = nil
	die_respawned[player_name] = nil
end)

minetest.register_on_dieplayer(function(player)
	local player_name = player:get_player_name()
	if not player_name then return end
	die_respawned[player_name] = false
	die_time[player_name] = die_timeout
end)

minetest.register_on_respawnplayer(function(player)
	local player_name = player:get_player_name()
	if not player_name then return end
	die_respawned[player_name] = true
end)


-- Following edits by gravgun

item_drop.drop_callbacks = {}
item_drop.pickup_callbacks = {}

-- on_drop(dropper, drop_entity, itemstack)
function item_drop.add_drop_callback(on_drop)
	table.insert(item_drop.drop_callbacks, on_drop)
end

-- on_pickup(picker, itemstack)
function item_drop.add_pickup_callback(on_pickup)
	table.insert(item_drop.pickup_callbacks, on_pickup)
end

-- Idea is to have a radius pickup range around the player, whatever the height
-- We need to have a radius that will at least contain 1 node distance at the player's feet
-- Using simple trigonometry, we get that we need a radius of
--  sqrt(pickup_range² + player_half_height²)
local pickup_range = 1.3
local pickup_range_squared = pickup_range*pickup_range
local player_half_height = 0.9
local scan_range = math.sqrt(player_half_height*player_half_height + pickup_range_squared)
-- Node drops are insta-pickup, everything else (player drops) are not
local delay_before_playerdrop_pickup = 1
-- Time in which the node comes to the player
local pickup_duration = 0.1
-- Little treshold so the items aren't already on the player's middle
local pickup_inv_duration = 1/pickup_duration*0.7

local function tick()
	local tstamp = minetest.get_us_time()
	for _,player in ipairs(minetest.get_connected_players()) do
		local player_name = player:get_player_name()
		if die_time[player_name] and die_time[player_name] < 1 then
			if player:get_hp() > 0 or not enable_damage then
				local pos = player:getpos()
				pos.y = pos.y + player_half_height
				local inv = player:get_inventory()

				if inv then
					for _,object in ipairs(minetest.get_objects_inside_radius(pos, scan_range)) do
						local luaEnt = object:get_luaentity()
						if luaEnt and luaEnt.name == "__builtin:item" then
							local ticky = luaEnt.item_drop_min_tstamp
							if ticky then
								if tstamp >= ticky then
									luaEnt.item_drop_min_tstamp = nil
								end
							elseif not luaEnt.item_drop_nopickup then
								-- Point-line distance computation, heavily simplified since the wanted line,
								-- being the player, is completely upright (no variation on X or Z)
								local pos2 = object:getpos()
								-- No sqrt, avoid useless computation
								-- (just take the radius, compare it to the square of what you want)
								-- Pos order doesn't really matter, we're squaring the result
								-- (but don't change it, we use the cached values afterwards)
								local dX = pos.x-pos2.x
								local dZ = pos.z-pos2.z
								local playerDistance = dX*dX+dZ*dZ
								if playerDistance <= pickup_range_squared then
									local itemStack = ItemStack(luaEnt.itemstring)
									if inv:room_for_item("main", itemStack) then
										local vec = {x=dX, y=pos.y-pos2.y, z=dZ}
										vec.x = vec.x*pickup_inv_duration
										vec.y = vec.y*pickup_inv_duration
										vec.z = vec.z*pickup_inv_duration
										object:setvelocity(vec)
										luaEnt.physical_state = false
										luaEnt.object:set_properties({
											physical = false
										})
										-- Mark the object as already picking up
										luaEnt.item_drop_nopickup = true

										minetest.after(pickup_duration, function()
											local lua = luaEnt
											if object == nil or lua == nil or lua.itemstring == nil then
												return
											end
											if inv:room_for_item("main", itemStack) then
												inv:add_item("main", itemStack)
												if luaEnt.itemstring ~= "" then
													minetest.sound_play("item_drop_pickup", {pos = pos, gain = 0.3, max_hear_distance = 8})
												end
												luaEnt.itemstring = ""
												object:remove()
												for i, cb in ipairs(item_drop.pickup_callbacks) do
													cb(player, itemstack)
												end
											else
												object:setvelocity({x = 0,y = 0,z = 0})
												luaEnt.physical_state = true
												luaEnt.object:set_properties({
													physical = true
												})
												luaEnt.item_drop_nopickup = nil
											end
										end)
									end
								end
							end
						end
					end
				end
			end
		else
			if die_respawned[player_name] then
				die_time[player_name] = (die_time[player_name] or die_timeout) - TICK_UPDATE
			end
		end
	end
	minetest.after(TICK_UPDATE, tick)
end

local mt_handle_node_drops = minetest.handle_node_drops
function minetest.handle_node_drops(pos, drops, digger)
	if digger and digger.is_fake_player then -- Pipeworks' wielders
		mt_handle_node_drops(pos, drops, digger)
		return
	end
	local inv
	if creative_mode and digger and digger:is_player() then
		inv = digger:get_inventory()
	end
	for _,item in ipairs(drops) do
		local count, name
		if type(item) == "string" then
			count = 1
			name = item
		else
			count = item:get_count()
			name = item:get_name()
		end
		if not inv or not inv:contains_item("main", ItemStack(name)) then
			for i=1,count do
				local obj
				local x = math.random(1, 5)
				if math.random(1,2) == 1 then x = -x end

				local z = math.random(1, 5)
				if math.random(1,2) == 1 then z = -z end

				obj = minetest.spawn_item(pos, name)
				if obj ~= nil then
					obj:setvelocity({x=1/x, y=obj:getvelocity().y, z=1/z})
				end
			end
		end
	end
end

local mt_item_drop = minetest.item_drop
function minetest.item_drop(itemstack, dropper, pos)
	if dropper.is_player then
		local v = dropper:get_look_dir()
		local p = {x=pos.x, y=pos.y+1.2, z=pos.z}
		local cs = itemstack:get_count()
		if dropper:get_player_control().sneak then
			cs = 1
		end
		local item = itemstack:take_item(cs)
		local obj = core.add_item(p, item)
		if obj then
			v.x = v.x*2
			v.y = v.y*2 + 2
			v.z = v.z*2
			obj:setvelocity(v)
			obj:get_luaentity().item_drop_min_tstamp = minetest.get_us_time() + delay_before_playerdrop_pickup * 1000000
			for i, cb in ipairs(item_drop.drop_callbacks) do
				cb(dropper, obj, itemstack)
			end
		end
	else
		core.add_item(pos, itemstack)
	end
	return itemstack
end

if minetest.setting_getbool("log_mods") then
	minetest.log("action", "[item_drop] item_drop overriden: " .. tostring(mt_item_drop) .. " " .. tostring(minetest.item_drop))
	minetest.log("action", "[item_drop] loaded.")
end

tick()