add feather falling (#73)

* add feather falling

add feather falling

* add feather falling to init.lua

add feather falling routine to globalstep

* add feather falling to readme

add feather falling to readme

3d_armor/README.md

@@ -254,7 +254,7 @@ The above allows armor to block/prevent new damage types but you also need to as
 ## Groups used by 3d_Armor
 3d_armor has many default groups already registered, these are categorized under 4 main headings
  - **Elements:** armor_head, armor_torso, armor_legs, armor_feet
- - **Attributes:** armor_heal, armor_fire, armor_water
+ - **Attributes:** armor_heal, armor_fire, armor_water, armor_feather
  - **Physics:** physics_jump, physics_speed, physics_gravity
  - **Durability:** armor_use, flammable
  
@@ -334,6 +334,9 @@ The below Diamond chestplate has a 12% chance to completely block all damage (ar
 		damage_groups = {cracky=2, snappy=1, choppy=1, level=3},
 	})
 
+#### Armor_feather
+***"Armor_feather"*** will slow a player when falling. This only has one level or state, which is armor_feather=1
+
 ### Physics
 The physics attributes supported by 3d_armor are ***physics_jump, physics_speed and physics_gravity***. Although 3d_armor supports the use of this with no other mods it is recommended that the mod [player_monoids](https://forum.minetest.net/viewtopic.php?t=14895) is used to help with intermod compatability. 
 

3d_armor/api.lua

@@ -112,7 +112,7 @@ armor = {
 	timer = 0,
 	elements = {"head", "torso", "legs", "feet"},
 	physics = {"jump", "speed", "gravity"},
-	attributes = {"heal", "fire", "water"},
+	attributes = {"heal", "fire", "water", "feather"},
 	formspec = "image[2.5,0;2,4;armor_preview]"..
 		default.gui_bg..
 		default.gui_bg_img..
@@ -183,6 +183,7 @@ armor.config = {
 	water_protect = true,
 	fire_protect = minetest.get_modpath("ethereal") ~= nil,
 	fire_protect_torch = minetest.get_modpath("ethereal") ~= nil,
+	feather_fall = true,
 	punch_damage = true,
 }
 

3d_armor/init.lua

@@ -440,6 +440,20 @@ end, true)
 
 minetest.register_globalstep(function(dtime)
 	timer = timer + dtime
+
+	if armor.config.feather_fall == true then
+		for _,player in pairs(minetest.get_connected_players()) do
+			local name = player:get_player_name()
+			if armor.def[name].feather > 0 then
+				local vel_y = player:get_velocity().y
+				if vel_y < 0 and vel_y < 3 then
+					vel_y = -(vel_y * 0.05)
+					player:add_velocity({x = 0, y = vel_y, z = 0})
+				end
+			end
+		end
+	end
+
 	if timer <= armor.config.init_delay then
 		return
 	end