From 9062a6e22efe6d8199c07cda82caf656fb322ce9 Mon Sep 17 00:00:00 2001
From: Sumyjkl <sumianvoice@gmail.com>
Date: Sun, 17 Jul 2022 23:14:24 +1000
Subject: [PATCH] add node_head_top to check to make sure you won't clip
 through blocks before going out of swim / fly mode

---
 mods/PLAYER/mcl_playerinfo/init.lua |  9 +++++++--
 mods/PLAYER/mcl_playerplus/init.lua | 14 ++++++++++----
 2 files changed, 17 insertions(+), 6 deletions(-)

diff --git a/mods/PLAYER/mcl_playerinfo/init.lua b/mods/PLAYER/mcl_playerinfo/init.lua
index 9c5d1433f..1f1b84749 100644
--- a/mods/PLAYER/mcl_playerinfo/init.lua
+++ b/mods/PLAYER/mcl_playerinfo/init.lua
@@ -33,11 +33,14 @@ local function get_player_nodes(player_pos)
 
 	work_pos.y = work_pos.y + 1.5 -- head level
 	local node_head = node_ok(work_pos)
+	work_pos.y = work_pos.y + 0.5 -- top of head level, at collision box height
+	local node_head_top = node_ok(work_pos)
+	work_pos.y = work_pos.y - 0.5
 
 	work_pos.y = work_pos.y - 1.2 -- feet level
 	local node_feet = node_ok(work_pos)
 
-	return node_stand, node_stand_below, node_head, node_feet
+	return node_stand, node_stand_below, node_head, node_feet, node_head_top
 end
 
 minetest.register_globalstep(function(dtime)
@@ -62,11 +65,12 @@ minetest.register_globalstep(function(dtime)
 		local pos = player:get_pos()
 
 		-- what is around me?
-		local node_stand, node_stand_below, node_head, node_feet = get_player_nodes(pos)
+		local node_stand, node_stand_below, node_head, node_feet, node_head_top = get_player_nodes(pos)
 		mcl_playerinfo[name].node_stand = node_stand
 		mcl_playerinfo[name].node_stand_below = node_stand_below
 		mcl_playerinfo[name].node_head = node_head
 		mcl_playerinfo[name].node_feet = node_feet
+		mcl_playerinfo[name].node_head_top = node_head_top
 
 	end
 
@@ -81,6 +85,7 @@ minetest.register_on_joinplayer(function(player)
 		node_feet = "",
 		node_stand = "",
 		node_stand_below = "",
+		node_head_top = "",
 	}
 
 end)
diff --git a/mods/PLAYER/mcl_playerplus/init.lua b/mods/PLAYER/mcl_playerplus/init.lua
index 48b09adae..cdee0b798 100644
--- a/mods/PLAYER/mcl_playerplus/init.lua
+++ b/mods/PLAYER/mcl_playerplus/init.lua
@@ -118,7 +118,7 @@ function limit_vel_yaw(player_vel_yaw, yaw)
 	return player_vel_yaw
 end
 
-local node_stand, node_stand_below, node_head, node_feet
+local node_stand, node_stand_below, node_head, node_feet, node_head_top
 local is_swimming
 
 -- This following part is 2 wrapper functions for player:set_bones
@@ -377,7 +377,10 @@ minetest.register_globalstep(function(dtime)
 			set_properties_conditional(player,{collisionbox = {-0.312,0,-0.312,0.312,0.8,0.312}, eye_height = 0.5, nametag_color = { r = 225, b = 225, a = 225, g = 225 }})
 			-- control body bone when swimming
 			set_bone_position_conditional(player,"Body_Control", vector.new(0,6.3,0), vector.new(degrees(dir_to_pitch(player_velocity)) - 90,-player_vel_yaw + yaw + 180,0))
-		elseif mcl_playerinfo[name].node_head == "air" or get_item_group(mcl_playerinfo[name].node_head, "water") ~= 0 then
+		elseif (mcl_playerinfo[name].node_head_top == "air" -- make sure the collision box is not going to clip through the ceiling
+		or get_item_group(mcl_playerinfo[name].node_head_top, "water") ~= 0)
+		and (mcl_playerinfo[name].node_head == "air"
+		or get_item_group(mcl_playerinfo[name].node_head, "water") ~= 0) then
 			-- sets eye height, and nametag color accordingly
 			is_swimming = false
 			set_properties_conditional(player,{collisionbox = {-0.312,0,-0.312,0.312,1.8,0.312}, eye_height = 1.5, nametag_color = { r = 225, b = 225, a = 225, g = 225 }})
@@ -401,13 +404,15 @@ minetest.register_globalstep(function(dtime)
 			node_stand_below = mcl_playerinfo[name].node_stand_below
 			node_head = mcl_playerinfo[name].node_head
 			node_feet = mcl_playerinfo[name].node_feet
+			node_head_top = mcl_playerinfo[name].node_head_top
 			if not node_stand or not node_stand_below or not node_head or not node_feet then
 				return
 			end
 			if (not minetest.registered_nodes[node_stand]
 			or not minetest.registered_nodes[node_stand_below]
 			or not minetest.registered_nodes[node_head]
-			or not minetest.registered_nodes[node_feet]) then
+			or not minetest.registered_nodes[node_feet]
+			or not minetest.registered_nodes[node_head_top]) then
 				return
 			end
 
@@ -466,7 +471,8 @@ minetest.register_globalstep(function(dtime)
 		local node_stand_below = mcl_playerinfo[name].node_stand_below
 		local node_head = mcl_playerinfo[name].node_head
 		local node_feet = mcl_playerinfo[name].node_feet
-		if not node_stand or not node_stand_below or not node_head or not node_feet then
+		local node_head_top = mcl_playerinfo[name].node_head_top
+		if not node_stand or not node_stand_below or not node_head or not node_feet or not node_head_top then
 			return
 		end