Add secondary sprint key

README.md

@@ -9,11 +9,13 @@ This sprinting mod was inspired by GunshipPenguin's own [sprinting mod](https://
 
 The speed and jump multipliers, as well as hotkeys, can be configured directly from the advanced settings menu in the sprint subsection of the top-level Mods section. You can also configure sprint directly from `minetest.conf` with the settings listed below.
 
-| Name           | Type   | Description           |
-| -------------- | ------ | --------------------- |
-| sprint_primary | string | Primary sprinting key |
-| sprint_speed   | float  | Speed multiplier      |
-| sprint_jump    | float  | Jump multiplier       |
-| sprint_dir     | bool   | Directional sprinting |
+| Name                 | Type   | Description                |
+| -------------------- | ------ | -------------------------- |
+| sprint_primary       | string | Primary sprinting key      |
+| sprint_second        | string | Secondary sprinting key    |
+| sprint_enable_second | bool   | Allow secondary sprint key |
+| sprint_speed         | float  | Speed multiplier           |
+| sprint_jump          | float  | Jump multiplier            |
+| sprint_dir           | bool   | Directional sprinting      |
 
-`sprint_primary` is the codename of the primary sprint key which causes the speed and jump multipliers to be applied to the player while it is held. If `sprint_dir` is set to `true`, players can only sprint while moving forward.
+`sprint_primary` is the codename of the primary sprint key which causes the speed and jump multipliers to be applied to the player while it is held. If `sprint_dir` is set to `true`, players can only sprint while moving forward. `sprint_second` defines a key that if `sprint_enable_second` is set to `true` (default) triggers sprinting when pressed twice within 0.8 seconds.

init.lua

@@ -1,23 +1,26 @@
 -- sprint/init.lua
 
 local sprinting = {}
-local SPEED     = minetest.settings:get("sprint_speed")   or 1.8
-local JUMP      = minetest.settings:get("sprint_jump")    or 1.1
-local PRIMARY   = minetest.settings:get("sprint_primary") or "aux1"
-local DIR       = minetest.settings:get("sprint_dir")     or true
+local secondary = {}
+local SPEED     = minetest.settings:get("sprint_speed")         or 1.8
+local JUMP      = minetest.settings:get("sprint_jump")          or 1.1
+local PRIMARY   = minetest.settings:get("sprint_primary")       or "aux1"
+local SECOND    = minetest.settings:get("sprint_second")        or "up"
+local DIR       = minetest.settings:get("sprint_dir")           or true
+local ALLOW_SEC = minetest.settings:get("sprint_enable_second")
 
 ---
 --- Functions
 ---
 
-local function start_sprint(player, name)
+local function start_sprint(player, name, trigger)
 	player:set_physics_override({speed = SPEED, jump = JUMP})
-	sprinting[name] = true
+	sprinting[name] = {is = true, trigger = trigger}
 end
 
 local function stop_sprint(player, name)
 	player:set_physics_override({speed = 1, jump = 1})
-	sprinting[name] = false
+	sprinting[name] = {is = false}
 end
 
 ---
@@ -29,6 +32,12 @@ minetest.register_globalstep(function(dtime)
 		local name = player:get_player_name()
 		local ctrl = player:get_player_control()
 
+		if not sprinting[name] then
+			sprinting[name] = {is = false}
+		end
+
+		local spr  = sprinting[name]
+
 		local allow = true
 		if DIR == true then
 			if not ctrl.up then
@@ -36,11 +45,45 @@ minetest.register_globalstep(function(dtime)
 			end
 		end
 
-		if ctrl[PRIMARY] and allow and not sprinting[name] then
-			start_sprint(player, name)
-		elseif (not ctrl[PRIMARY] and sprinting[name] == true) or
-		 		(ctrl[PRIMARY] and not allow and sprinting[name] == true) then
+		-- Primary Key
+		if ctrl[PRIMARY] and allow and not spr.is then
+			start_sprint(player, name, "primary")
+		elseif ((not ctrl[PRIMARY] and spr.is) or
+		 		(ctrl[PRIMARY] and not allow and spr.is))
+						and spr.trigger == "primary" then
 			stop_sprint(player, name)
 		end
+
+		-- Secondary Key
+		if ALLOW_SEC ~= "false" and SECOND and SECOND ~= "" and spr.trigger ~= "primary" then
+			if not secondary[name] then
+				secondary[name] = {count = 0, time = 0, last = false}
+			end
+
+			if ctrl[SECOND] ~= secondary[name].last then
+				if secondary[name].time > 0.8 and not spr.is and
+				 		secondary[name].count > 0 and secondary[name].count < 3 then
+					secondary[name] = {count = 0, time = 0, last = false}
+					return
+				end
+
+				if secondary[name].count < 3 and ctrl[SECOND] ~= secondary[name].last then
+					secondary[name].count = secondary[name].count + 1
+					secondary[name].last  = ctrl[SECOND]
+				end
+
+				if (secondary[name].count == 3 and ctrl[SECOND]) and allow and not spr.is then
+					start_sprint(player, name, "secondary")
+				elseif ((secondary[name].count > 3 or not ctrl[SECOND]) or not allow) and
+						spr.is then
+					stop_sprint(player, name)
+					secondary[name] = {count = 0, time = 0, last = false}
+				end
+			end
+
+			if not spr.is and secondary[name].count ~= 0 then
+				secondary[name].time = secondary[name].time + dtime
+			end
+		end
 	end
 end)

settingtypes.txt

@@ -4,6 +4,15 @@
 #    This defaults to aux1, which is also used if fast_move is enabled.
 sprint_primary (Primary Sprint Key) string aux1
 
+#    Secondary key that triggers the speed and jump multipliers when double-pressed
+#    and held for the duration. This is most convenient to map to the "up" ("forward")
+#    key, as it allows seemlessly enabling sprint by simply double-tapping forward
+#    without having to move your hand to reach another key.
+sprint_second (Secondary Sprint Key) string up
+
+#    If disabled, the secondary sprint key (sprint_second) is not allowed.
+sprint_enable_second (Allow Secondary Sprint Key) bool true
+
 #    Speed multiplier applied when sprinting.
 #    Sprint key configured with the sprint_primary setting.
 sprint_speed (Speed Multiplier) float 1.8