add 2 value sanity checks which should not be needed but are for any reason

game crashed because of these values being nil, I don't know how these values could even become nil, but whatever.
Interestingly, I never found the wagon entity that was causing the crashs

1 files changed, 10 insertions, 0 deletions

diff --git a/wagons.lua b/wagons.lua
index 6944e76..287b723 100644
--- a/wagons.lua
+++ b/wagons.lua
@@ -174,6 +174,12 @@ end
 function wagon:on_step(dtime)

 	local t=os.clock()

 	local pos = self.object:getpos()

+	

+	if not pos then

+		print("["..self.unique_id.."][fatal] missing position (object:getpos() returned nil)")

+		return

+	end

+	

 	if not self.initialized_pre then 

 		print("[advtrains] wagon stepping while not yet initialized_pre, returning")

 		self.object:setvelocity({x=0,y=0,z=0})

@@ -269,6 +275,10 @@ function wagon:on_step(dtime)
 		self.object:setvelocity({x=0, y=0, z=0})

 		return

 	end

+	if not self.pos_in_train then

+		print("["..self.unique_id.."][fatal] no pos_in_train set.")

+		return

+	end

 	

 	local index=advtrains.get_real_path_index(self:train(), self.pos_in_train)

 	--print("trainindex "..gp.index.." wagonindex "..index)