Allow switching with keys

functions.lua

@@ -19,10 +19,45 @@ function boost_cart:is_rail(pos)
 	return minetest.get_item_group(node, "rail") ~= 0
 end
 
-function boost_cart:get_rail_direction(pos_, dir_)
+function boost_cart:get_rail_direction(pos_, dir_, ctrl, old_switch)
 	local pos = vector.round(pos_)
 	local dir = vector.new(dir_)
 	local cur = nil
+	local left_check, right_check = true, true
+	old_switch = old_switch or 0
+	
+	-- Check left and right
+	local left = {x=0, y=0, z=0}
+	local right = {x=0, y=0, z=0}
+	if dir.z ~= 0 and dir.x == 0 then
+		left.x = -dir.z
+		right.x = dir.z
+	elseif dir.x ~= 0 and dir.z == 0 then
+		left.z = dir.x
+		right.z = -dir.x
+	end
+	
+	if ctrl then
+		if old_switch == 1 then
+			left_check = false
+		elseif old_switch == 2 then
+			right_check = false
+		end
+		if ctrl.left and left_check then
+			cur = vector.add(pos, left)
+			if boost_cart:is_rail(cur) then
+				return left, 1
+			end
+			left_check = false
+		end
+		if ctrl.right and right_check then
+			cur = vector.add(pos, right)
+			if boost_cart:is_rail(cur) then
+				return right, 2
+			end
+			right_check = true
+		end
+	end
 	
 	-- Front
 	dir.y = 0
@@ -45,58 +80,20 @@ function boost_cart:get_rail_direction(pos_, dir_)
 		return dir
 	end
 	
-	-- Left, right
-	dir.y = 0
-	
-	-- Check left and right
-	local view, opposite, val
-	
-	if dir.x == 0 and dir.z ~= 0 then
-		view = "z"
-		other = "x"
-		if dir.z < 0 then
-			val = {1, -1}
-		else
-			val = {-1, 1}
-		end
-	elseif dir.z == 0 and dir.x ~= 0 then
-		view = "x"
-		other = "z"
-		if dir.x > 0 then
-			val = {1, -1}
-		else
-			val = {-1, 1}
-		end
-	else
-		return {x=0, y=0, z=0}
-	end
-	
-	dir[view] = 0
-	dir[other] = val[1]
-	cur = vector.add(pos, dir)
+	-- Left, if not already checked
+	if left_check then
+		cur = vector.add(pos, left)
 		if boost_cart:is_rail(cur) then
-		return dir
+			return left
+		end
 	end
 	
-	-- Down
-	dir.y = -1
-	cur = vector.add(pos, dir)
+	-- Right, if not already checked
+	if right_check then
+		cur = vector.add(pos, right)
 		if boost_cart:is_rail(cur) then
-		return dir
+			return right
 		end
-	dir.y = 0
-	
-	dir[other] = val[2]
-	cur = vector.add(pos, dir)
-	if boost_cart:is_rail(cur) then
-		return dir
-	end
-	
-	-- Down
-	dir.y = -1
-	cur = vector.add(pos, dir)
-	if boost_cart:is_rail(cur) then
-		return dir
 	end
 	
 	return {x=0, y=0, z=0}

init.lua

@@ -29,7 +29,8 @@ boost_cart.cart = {
 	punch = false, -- used to re-send velocity and position
 	velocity = {x=0, y=0, z=0}, -- only used on punch
 	old_dir = {x=0, y=0, z=0},
-	old_pos = nil
+	old_pos = nil,
+	old_switch = nil
 }
 
 function boost_cart.cart:on_rightclick(clicker)
@@ -42,7 +43,7 @@ function boost_cart.cart:on_rightclick(clicker)
 		clicker:set_detach()
 	elseif not self.driver then
 		self.driver = player_name
-		clicker:set_attach(self.object, "", {x=0, y=5, z=0}, {x=0, y=0, z=0})
+		clicker:set_attach(self.object, "", {x=0,y=0.5,z=0}, {x=0,y=0,z=0})
 	end
 end
 
@@ -57,6 +58,7 @@ function boost_cart.cart:on_punch(puncher, time_from_last_punch, tool_capabiliti
 
 	if puncher:get_player_control().sneak then
 		if self.driver then
+			default.player_attached[self.driver] = nil
 			local player = minetest.get_player_by_name(self.driver)
 			if player then
 				player:set_detach()
@@ -111,7 +113,7 @@ function boost_cart.cart:on_step(dtime)
 		return
 	end
 	
-	local dir = false
+	local dir, last_switch = nil, nil
 	local pos = self.object:getpos()
 	if self.old_pos and not self.punch then
 		local flo_pos = vector.floor(pos)
@@ -120,12 +122,19 @@ function boost_cart.cart:on_step(dtime)
 			return
 		end
 	end
+	local ctrl = nil
+	if self.driver then
+		local player = minetest.get_player_by_name(self.driver)
+		if player then
+			ctrl = player:get_player_control()
+		end
+	end
 	if self.old_pos then
 		local diff = vector.subtract(self.old_pos, pos)
 		for _,v in ipairs({"x","y","z"}) do
 			if math.abs(diff[v]) > 1.2 then
 				local expected_pos = vector.add(self.old_pos, self.old_dir)
-				dir = boost_cart:get_rail_direction(pos, self.old_dir)
+				dir, last_switch = boost_cart:get_rail_direction(pos, self.old_dir, ctrl, self.old_switch)
 				if vector.equals(dir, {x=0, y=0, z=0}) then
 					dir = false
 					pos = vector.new(expected_pos)
@@ -154,7 +163,7 @@ function boost_cart.cart:on_step(dtime)
 	
 	local max_vel = boost_cart.speed_max
 	if not dir then
-		dir = boost_cart:get_rail_direction(pos, cart_dir)
+		dir, last_switch = boost_cart:get_rail_direction(pos, cart_dir, ctrl, self.old_switch)
 	end
 	if vector.equals(dir, {x=0, y=0, z=0}) then
 		vel = {x=0, y=0, z=0}
@@ -194,9 +203,13 @@ function boost_cart.cart:on_step(dtime)
 					end
 				end
 			end
-			acc = acc + (speed_mod * 7)
+			acc = acc + (speed_mod * 8)
 		else
 			acc = acc - 0.4
+			-- Handbrake
+			if ctrl and ctrl.down then
+				acc = acc - 0.8
+			end
 		end
 		
 		local new_acc = {
@@ -210,6 +223,7 @@ function boost_cart.cart:on_step(dtime)
 	
 	self.old_pos = vector.new(pos)
 	self.old_dir = vector.new(dir)
+	self.old_switch = last_switch
 	
 	-- Limits
 	for _,v in ipairs({"x","y","z"}) do