Major improvements for flying entities

Previously, if the entity had the `can_fly` option enabled, when
going upwards or downwards, it went too fast, extremely fast, and its speed increases over time.

With this update, this no longer happens: you can customize your
own upwards and downwards maximum speed for any entity you want.

README.md

@@ -1,9 +1,9 @@
-# Library Mount [![Build status](https://github.com/Panquesito7/lib_mount/workflows/build/badge.svg)](https://github.com/Panquesito7/lib_mount/actions) [![License](https://img.shields.io/badge/license-LGPLv2.1%2B-blue.svg)](https://www.gnu.org/licenses/old-licenses/lgpl-2.1.en.html) [![ContentDB](https://content.minetest.net/packages/Panquesito7/lib_mount/shields/downloads/)](https://content.minetest.net/packages/Panquesito7/lib_mount/)
+# Library Mount [![Build status](https://github.com/minetest-mods/lib_mount/workflows/build/badge.svg)](https://github.com/minetest-mods/lib_mount/actions) [![License](https://img.shields.io/badge/license-LGPLv2.1%2B-blue.svg)](https://www.gnu.org/licenses/old-licenses/lgpl-2.1.en.html) [![ContentDB](https://content.minetest.net/packages/Panquesito7/lib_mount/shields/downloads/)](https://content.minetest.net/packages/Panquesito7/lib_mount/)
 
 Made by [blert2112](https://github.com/blert2112).\
 Handed over to [Panquesito7](https://github.com/Panquesito7).
 
-Current version: 1.2
+Current version: 1.3
 
 ## Dependencies
 
@@ -29,11 +29,11 @@ See [`LICENSE.md`](LICENSE.md) for information.
 
 ## Installation
 
-- Unzip the archive, rename the folder to `lib_mount` and place it in ../minetest/mods/
+- Unzip the archive, rename the folder to `lib_mount` and place it in `../minetest/mods/`.
 
-- GNU/Linux: If you use a system-wide installation place it in ~/.minetest/mods/.
+- GNU/Linux: If you use a system-wide installation, place it in `~/.minetest/mods/`.
 
-- If you only want this to be used in a single world, place the folder in worldmods/ in your world directory.
+- If you only want this to be used in a single world, place the folder in `worldmods/` in your world directory.
 
 For further information or help, see:\
 <http://wiki.minetest.net/Installing_Mods>.

init.lua

@@ -278,13 +278,13 @@ function lib_mount.drive(entity, dtime, is_mob, moving_anim, stand_anim, jump_he
 				velo.y = velo.y + (jump_height * 3) + 1
 				acce_y = acce_y + (acce_y * 3) + 1
 			end
-			if can_go_down and can_go_up and can_fly and can_fly == true then
+			if can_go_up and can_fly and can_fly == true then
 				velo.y = velo.y + 1
 				acce_y = acce_y + 1
 			end
 		end
 		if ctrl.sneak then
-			if can_go_down and can_go_up and can_fly and can_fly == true then
+			if can_go_down and can_fly and can_fly == true then
 				velo.y = velo.y - 1
 				acce_y = acce_y - 1
 			end
@@ -317,6 +317,24 @@ function lib_mount.drive(entity, dtime, is_mob, moving_anim, stand_anim, jump_he
 		return
 	end
 
+	-- Stop! (upwards and downwards; applies only if `can_fly` is enabled)
+	if can_fly == true then
+		local s2 = get_sign(velo.y)
+		local s3 = get_sign(acce_y)
+		velo.y = velo.y - 0.02 * s2
+		acce_y = acce_y - 0.02 * s3
+		if s2 ~= get_sign(velo.y) then
+			entity.object:set_velocity({x=0, y=0, z=0})
+			velo.y = 0
+			return
+		end
+		if s3 ~= get_sign(acce_y) then
+			entity.object:set_velocity({x=0, y=0, z=0})
+			acce_y = 0 -- luacheck: ignore
+			return
+		end
+	end
+
 	-- enforce speed limit forward and reverse
 	local max_spd = entity.max_speed_reverse
 	if get_sign(entity.v) >= 0 then
@@ -326,6 +344,25 @@ function lib_mount.drive(entity, dtime, is_mob, moving_anim, stand_anim, jump_he
 		entity.v = entity.v - get_sign(entity.v)
 	end
 
+	-- Enforce speed limit when going upwards or downwards (applies only if `can_fly` is enabled)
+	if can_fly == true then
+		local max_spd_flying = entity.max_speed_downwards
+		if get_sign(velo.y) >= 0 or get_sign(acce_y) >= 0 then
+			max_spd_flying = entity.max_speed_upwards
+		end
+
+		if math.abs(velo.y) > max_spd_flying then
+			velo.y = velo.y - get_sign(velo.y)
+		end
+		if velo.y > max_spd_flying then -- This check is to prevent exceeding the maximum speed; but the above check also prevents that.
+			velo.y = velo.y - get_sign(velo.y)
+		end
+
+		if math.abs(acce_y) > max_spd_flying then
+			acce_y = acce_y - get_sign(acce_y)
+		end
+	end
+
 	-- Set position, velocity and acceleration
 	local p = entity.object:get_pos()
 	local new_velo = {x=0, y=0, z=0}
@@ -337,6 +374,7 @@ function lib_mount.drive(entity, dtime, is_mob, moving_anim, stand_anim, jump_he
 	if ni == "air" then
 		if can_fly == true then
 			new_acce.y = 0
+			acce_y = acce_y - get_sign(acce_y) -- When going down, this will prevent from exceeding the maximum speed.
 		end
 	elseif ni == "liquid" then
 		if entity.terrain_type == 2 or entity.terrain_type == 3 then