From 8c579b208408244cc4c76c1228955962dd8cadac Mon Sep 17 00:00:00 2001
From: MewMew <mail@mewmew.net>
Date: Mon, 30 Mar 2020 20:10:21 +0200
Subject: [PATCH] players no longer get murdered by water

---
 modules/sticky_landfill.lua | 27 ++++++++++++++++++++++++---
 1 file changed, 24 insertions(+), 3 deletions(-)

diff --git a/modules/sticky_landfill.lua b/modules/sticky_landfill.lua
index 4c570390..096b47aa 100644
--- a/modules/sticky_landfill.lua
+++ b/modules/sticky_landfill.lua
@@ -1,5 +1,7 @@
 -- landfill is sticky, making it difficult to isolate
 
+local math_sqrt = math.sqrt
+local math_floor = math.floor
 local table_insert = table.insert
 
 local vectors = {}
@@ -16,7 +18,6 @@ local vectors_2 = {{0, -1}, {0, 1}, {-1, 0}, {1, 0}}
 local function is_position_sticky(surface, position)
 	local tile = surface.get_tile(position)
 	if not tile.collides_with("resource-layer") then return end
-	
 	for _, v in pairs(vectors_2) do
 		tile = surface.get_tile({position.x + v[1], position.y + v[2]})
 		if not tile.collides_with("resource-layer") then
@@ -28,14 +29,27 @@ end
 local function move_tile(surface, tile_name, position)	
 	for key, v in pairs(vectors) do
 		local p = {x = position.x + v[1], y = position.y + v[2]}
-
 		if is_position_sticky(surface, p) then
 			surface.set_tiles({{name = tile_name, position = p}}, true)
 			return
 		end
 	end
 end
-	
+
+local function safe_players_from_drowning(surface, tiles)
+	local a = math_floor(math_sqrt(#tiles)) + 2
+	local left_top = {x = tiles[1].position.x - 1, y = tiles[1].position.y - 1}
+	local area = {{left_top.x, left_top.y}, {left_top.x + a + 2, left_top.y + a + 2}}
+	local players = {}
+	for _, character in pairs(surface.find_entities_filtered({area = area, name = "character"})) do
+		if character.player then
+			table_insert(players, {character.player, {character.player.position.x, character.player.position.y}})
+			character.player.teleport({0, 0}, surface)
+		end	
+	end	
+	return players
+end
+
 local function sticky(surface, tiles, tile_name)
 	local revert_tiles = {}
 	local revert_entities = {}
@@ -51,6 +65,9 @@ local function sticky(surface, tiles, tile_name)
 		end
 		i = i + 1	
 	end
+	
+	local players = safe_players_from_drowning(surface, tiles)
+	
 	surface.set_tiles(revert_tiles, true)
 	
 	for _, placed_tile in pairs(tiles) do
@@ -60,6 +77,10 @@ local function sticky(surface, tiles, tile_name)
 	for _, entity in pairs(revert_entities) do
 		surface.create_entity(entity)
 	end
+	
+	for _, v in pairs(players) do
+		v[1].teleport(v[2], surface)
+	end
 end
 
 local function on_player_built_tile(event)