This is a really small tutorial on routing.

First I would like to apologize if I use wrong words about some stuff, my CAW is in Finnish and I have to translate the words.

In Sims 3 worlds, it's really important to have your routing done properly, so that the world doesn't lag when you play it. Other things can cause lag in a world too of course, but routing is one major one, and can cause serious trouble if not taken care of.

So, I made a tiny little beach to represent what I am trying to explain here. (click the boxes to show pics)

Moderator note: Broken routing lines have since been found to be harmless, and purely graphical- please see this information.



A this point I have done nothing on the routing. I just made a beach, slammed a piece of road and a lot there, plus a bunch of plants.

Here is the same beach with visible routing data (press view, show routing data)



Now I have marked the problem spots with red.



As you can see, some of the lines do not connect to each other properly, but are cut. That causes routing issues and lag. Now you may wonder " but it's just a tiny area, how can that effect anything?". Imagine that you have hundreds if not thousands of cut lines like that in a world. One dot that has no lines connected to it can already make a world lag massively. Cause the game makes NPC's spawn everywhere in the world that is not marked non-routable. So imagine a sim spawning on top of a dot that has no lines connected. The sim has nowhere to go and is therefore stuck. Causes LAG.

So to start fix this problem I first pressed rebuild routing data to see the problem spots in real time, as they are right now. And I remarked them.



Now, it's hard to see under the plants and behind them, so I hid them. (View - Levels/layers - untick plants)



First I wanna take care of the cliffs. I don't want my sims wandering there, so I paint over them with sims non-routable paint. (terrain - routing - sims paint)



Then I press rebuild routing data, and voila, cliff areas fixed.



I still have unconnected lines on the beach, so I take smoother brush, and smooth the areas that are problematic. Then press rebuild routing data. I was lucky to have them fixed at once.



Then I unhide the plants, and the beach area is done




I have one more thing to show you.



See how I added a big rock on the beach. Cause I have not fixed the routing, the sims can walk straight trough the rock, and that is not really realistic

So I press rebuild routing data, and the problem is fixed. (I also hid the rock to show the data better)





In closing:

• Rebuild routing data is your best friend
• You should press it every time before you export a world. No matter if you have made changes or not.
• A tiny error in routing can cause massive lag
• White lines and dots show where your sims can go
• Broken white lines/stand alone white dots cause lag.
• Red boxes around objects are their footprints
• Sometimes an object can hide a routing flaw under it, so you should always check your routing with objects hidden
• The blue paint is sims non-routable paint. You should use it everywhere you don't want sims to go.
• When using non-routable paints, make sure there are no spots inside it left un painted. (if a sims spawns to a spot like that, they get stuck and cause lag.)
• A hint: You need to move the camera a little for the routing data to update after pressing rebuild routing data.
• Another hint: You can place flowers or any other object to a spot that is tricky and does not fix the routing properly (sometimes there are stubborn lines), if that is convenient for that spot. Then press rebuild routing data, and hopefully the spot is then fixed.

Routing a world may seem like a massive job, but when you do it while building the world, bit by bit, you know it gets done well, and you can enjoy lag free world
(lag free=no lag that is caused by routing, this tutorial does not cover other issues that cause lag)

Hopefully you have learned something new, and find this tutorial useful