turning airutils into a lib

airutils_papi.lua

@@ -49,8 +49,8 @@ airutils.groups = {snappy=2,choppy=2,oddly_breakable_by_hand=2}
 -- PAPI node (default left)
 minetest.register_node("airutils:papi",{
 	description = "PAPI",
-	inventory_image = "papi.png",
-	wield_image = "papi.png",
+	--inventory_image = "papi.png",
+	--wield_image = "papi.png",
 	tiles = {"airutils_black.png", "airutils_u_black.png", "airutils_white.png",
 	"airutils_metal.png", {name = "airutils_red.png", backface_culling = true},},
 	groups = airutils.groups,

init.lua

@@ -20,5 +20,131 @@ function airutils.canDig(pos, player)
 		and player:get_player_name() == meta:get_string("owner")
 end
 
+function airutils.check_node_below(obj)
+    local pos_below = obj:get_pos()
+    if pos_below then
+        pos_below.y = pos_below.y - 2.5
+        local node_below = minetest.get_node(pos_below).name
+        local nodedef = minetest.registered_nodes[node_below]
+        local touching_ground = not nodedef or -- unknown nodes are solid
+		        nodedef.walkable or false
+        local liquid_below = not touching_ground and nodedef.liquidtype ~= "none"
+        return touching_ground, liquid_below
+    end
+    return nil, nil
+end
+
+function airutils.check_is_under_water(obj)
+	local pos_up = obj:get_pos()
+	pos_up.y = pos_up.y + 0.1
+	local node_up = minetest.get_node(pos_up).name
+	local nodedef = minetest.registered_nodes[node_up]
+	local liquid_up = nodedef.liquidtype ~= "none"
+	return liquid_up
+end
+
+function airutils.setText(self, vehicle_name)
+    local properties = self.object:get_properties()
+    local formatted = ""
+    if self.hp_max then
+        formatted = " Current hp: " .. string.format(
+           "%.2f", self.hp_max
+        )
+    end
+    if properties then
+        properties.infotext = "Nice ".. vehicle_name .." of " .. self.owner .. "." .. formatted
+        self.object:set_properties(properties)
+    end
+end
+
+function airutils.transfer_control(self, status)
+    if status == false then
+        self._command_is_given = false
+        if self._passenger then
+            minetest.chat_send_player(self._passenger,
+                core.colorize('#ff0000', " >>> The captain got the control."))
+        end
+        if self.driver_name then
+            minetest.chat_send_player(self.driver_name,
+                core.colorize('#00ff00', " >>> The control is with you now."))
+        end
+    else
+        self._command_is_given = true
+        if self._passenger then
+            minetest.chat_send_player(self._passenger,
+                core.colorize('#00ff00', " >>> The control is with you now."))
+        end
+        if self.driver_name then minetest.chat_send_player(self.driver_name," >>> The control was given.") end
+    end
+end
+
+--returns 0 for old, 1 for new
+function airutils.detect_player_api(player)
+    local player_proterties = player:get_properties()
+    local mesh = "character.b3d"
+    if player_proterties.mesh == mesh then
+        local models = player_api.registered_models
+        local character = models[mesh]
+        if character then
+            if character.animations.sit.eye_height then
+                return 1
+            else
+                return 0
+            end
+        end
+    end
+
+    return 0
+end
+
+--lift
+local function pitchroll2pitchyaw(aoa,roll)
+	if roll == 0.0 then return aoa,0 end
+	-- assumed vector x=0,y=0,z=1
+	local p1 = math.tan(aoa)
+	local y = math.cos(roll)*p1
+	local x = math.sqrt(p1^2-y^2)
+	local pitch = math.atan(y)
+	local yaw=math.atan(x)*math.sign(roll)
+	return pitch,yaw
+end
+
+function airutils.getLiftAccel(self, velocity, accel, longit_speed, roll, curr_pos, lift, max_height)
+    --lift calculations
+    -----------------------------------------------------------
+    max_height = max_height or 20000
+    local wing_config = 0
+    if self._wing_configuration then wing_config = self._wing_configuration end --flaps!
+    
+    local retval = accel
+    if longit_speed > 1 then
+        local angle_of_attack = math.rad(self._angle_of_attack + wing_config)
+        --local acc = 0.8
+        local daoa = deg(angle_of_attack)
+
+        --to decrease the lift coefficient at hight altitudes
+        local curr_percent_height = (100 - ((curr_pos.y * 100) / max_height))/100
 
+	    local rotation=self.object:get_rotation()
+	    local vrot = mobkit.dir_to_rot(velocity,rotation)
+	    
+	    local hpitch,hyaw = pitchroll2pitchyaw(angle_of_attack,roll)
 
+	    local hrot = {x=vrot.x+hpitch,y=vrot.y-hyaw,z=roll}
+	    local hdir = mobkit.rot_to_dir(hrot) --(hrot)
+	    local cross = vector.cross(velocity,hdir)
+	    local lift_dir = vector.normalize(vector.cross(cross,hdir))
+
+        local lift_coefficient = (0.24*abs(daoa)*(1/(0.025*daoa+3))^4*math.sign(angle_of_attack))
+        local lift_val = math.abs((lift*(vector.length(velocity)^2)*lift_coefficient)*curr_percent_height)
+        --minetest.chat_send_all('lift: '.. lift_val)
+
+        local lift_acc = vector.multiply(lift_dir,lift_val)
+        --lift_acc=vector.add(vector.multiply(minetest.yaw_to_dir(rotation.y),acc),lift_acc)
+
+        retval = vector.add(retval,lift_acc)
+    end
+    -----------------------------------------------------------
+    -- end lift
+    return retval
+end