# I can’t see more gates anymore

Finally I have the time again to make a more serious blog post here. You might be wondering what I have been up to lately? It has been mainly the [NL2000] scenery project that kept me busy. We are currently finishing the beta version of our next release and for the scenery of Schiphol airport I had promised to make nicely animated gates.

A while ago I already made some posts on mathematical calculations I was trying to make to calculate how a gate should animate to dock to a certain type of aircraft. I have now finished this tool as well and it is working very well I think. Let me say first that I will probably not release the tool as it is now, as some choices are hardcoded, which means that it only works with the gates as I designed them in GMax.

So what does this tool do? So tell it some basic things about your gate, for example the length of the different arms, the default angles of the arms, etc. Besides that you also tell it where the stoppoint of this specific gate is (seen from the reference point of the object). With this information and like maths it is possible to calculate with rotations (and extension of the gate arm) are needed to make sure the head of the gate ends up at the stoppoint. But of course the aircraft door is not at the stoppoint, it usally has an offset depending on the type of aircraft used. So I also gave the tool this kind of offset information for about 30 aircraft types. With that additional information I could the desired position of the head for each type of aircraft.

Of course to get a perfect match with the aircraft model used, the designer of the aircraft should have put the door on the correct location, but as most aircraft designers try to make their models as perfect as they can I think that should not be a very big issue.

As you would probably have guessed already, the gates make use of the ActiGate module I made. So the animation is triggered by setting the parking brake and depending on the type of aircraft you use (as identified by the module) you get a different animations. Which makes sure that the head of the gate should end up at your door. Once I had figured that out, all I had to do was make a the different gates used at the airport. Unfortunately they have a lot of variants, for each of which I had to adjust my models a little bit. As we also have quite detailed markings in the scenery, the gates needed to match the real ones as closely as possible. And when you know that Schiphol has about 90 gates in total, I think you can image that it took some time to finish this all.

Now you will probably wonder why I spend so much time on this, as FsX has a nice auto docking feature that should make things a lot easier. Well, I can only see that that is true. But (unfortunately) I had already promised to make these gates for this Fs2004 project (before FsX was there), so I had to finish them. And on the positive side I also learned some more tricks about tweaking animations. For example these gates have been tweaked with extending the SCEN section as CAT does. So that means that with this technique I could also condition the animation of attached effects. Maybe this new technique will make it into CAT as well, but for the moment I first want to study the new FsX techniques more to see which path is the best to go ahead on. I have seen enough gates for a the moment I guess, so the coming time I want to spend on exploring the new SDKs and looking at the new MDL format (and updating my tools where needed of course).