X-Git-Url: https://git.lizzy.rs/?a=blobdiff_plain;f=builtin%2Fgame%2Fforceloading.lua;h=5de4c3ad34902259c6ab64f8eccfc7dfd336542a;hb=3ad9a8f3a978b41a88ebf8a88690ad658cd132c7;hp=147f12fa074875c2e2bd206d28571355e0b9c763;hpb=c4359ff65cd8e4e754442b9f2ef7051a8eaa4241;p=minetest.git

diff --git a/builtin/game/forceloading.lua b/builtin/game/forceloading.lua
index 147f12fa0..5de4c3ad3 100644
--- a/builtin/game/forceloading.lua
+++ b/builtin/game/forceloading.lua
@@ -5,9 +5,13 @@ core.forceload_block = nil
 core.forceload_free_block = nil
 
 local blocks_forceloaded
+local blocks_temploaded = {}
 local total_forceloaded = 0
 
-local BLOCKSIZE = 16
+-- true, if the forceloaded blocks got changed (flag for persistence on-disk)
+local forceload_blocks_changed = false
+
+local BLOCKSIZE = core.MAP_BLOCKSIZE
 local function get_blockpos(pos)
 	return {
 		x = math.floor(pos.x/BLOCKSIZE),
@@ -15,32 +19,58 @@ local function get_blockpos(pos)
 		z = math.floor(pos.z/BLOCKSIZE)}
 end
 
-function core.forceload_block(pos)
+-- When we create/free a forceload, it's either transient or persistent. We want
+-- to add to/remove from the table that corresponds to the type of forceload, but
+-- we also need the other table because whether we forceload a block depends on
+-- both tables.
+-- This function returns the "primary" table we are adding to/removing from, and
+-- the other table.
+local function get_relevant_tables(transient)
+	if transient then
+		return blocks_temploaded, blocks_forceloaded
+	else
+		return blocks_forceloaded, blocks_temploaded
+	end
+end
+
+function core.forceload_block(pos, transient)
+	-- set changed flag
+	forceload_blocks_changed = true
+
 	local blockpos = get_blockpos(pos)
 	local hash = core.hash_node_position(blockpos)
-	if blocks_forceloaded[hash] ~= nil then
-		blocks_forceloaded[hash] = blocks_forceloaded[hash] + 1
+	local relevant_table, other_table = get_relevant_tables(transient)
+	if relevant_table[hash] ~= nil then
+		relevant_table[hash] = relevant_table[hash] + 1
 		return true
+	elseif other_table[hash] ~= nil then
+		relevant_table[hash] = 1
 	else
-		if total_forceloaded >= (tonumber(core.setting_get("max_forceloaded_blocks")) or 16) then
+		if total_forceloaded >= (tonumber(core.settings:get("max_forceloaded_blocks")) or 16) then
 			return false
 		end
 		total_forceloaded = total_forceloaded+1
-		blocks_forceloaded[hash] = 1
+		relevant_table[hash] = 1
 		forceload_block(blockpos)
 		return true
 	end
 end
 
-function core.forceload_free_block(pos)
+function core.forceload_free_block(pos, transient)
+	-- set changed flag
+	forceload_blocks_changed = true
+
 	local blockpos = get_blockpos(pos)
 	local hash = core.hash_node_position(blockpos)
-	if blocks_forceloaded[hash] == nil then return end
-	if blocks_forceloaded[hash] > 1 then
-		blocks_forceloaded[hash] = blocks_forceloaded[hash] - 1
+	local relevant_table, other_table = get_relevant_tables(transient)
+	if relevant_table[hash] == nil then return end
+	if relevant_table[hash] > 1 then
+		relevant_table[hash] = relevant_table[hash] - 1
+	elseif other_table[hash] ~= nil then
+		relevant_table[hash] = nil
 	else
 		total_forceloaded = total_forceloaded-1
-		blocks_forceloaded[hash] = nil
+		relevant_table[hash] = nil
 		forceload_free_block(blockpos)
 	end
 end
@@ -53,7 +83,7 @@ local function read_file(filename)
 	local t = f:read("*all")
 	f:close()
 	if t=="" or t==nil then return {} end
-	return core.deserialize(t)
+	return core.deserialize(t) or {}
 end
 
 local function write_file(filename, table)
@@ -74,6 +104,28 @@ core.after(5, function()
 	end
 end)
 
-core.register_on_shutdown(function()
+-- persists the currently forceloaded blocks to disk
+local function persist_forceloaded_blocks()
 	write_file(wpath.."/force_loaded.txt", blocks_forceloaded)
-end)
+end
+
+-- periodical forceload persistence
+local function periodically_persist_forceloaded_blocks()
+	
+	-- only persist if the blocks actually changed
+	if forceload_blocks_changed then
+		persist_forceloaded_blocks()
+
+		-- reset changed flag
+		forceload_blocks_changed = false
+	end
+
+	-- recheck after some time
+	core.after(10, periodically_persist_forceloaded_blocks)
+end
+
+-- persist periodically
+core.after(5, periodically_persist_forceloaded_blocks)
+
+-- persist on shutdown
+core.register_on_shutdown(persist_forceloaded_blocks)