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I Beta Team Bug Kill
 

XYZ-HASA fixes

This was a big one, and took longer than any other bug to characterize and track down. The Charter members of the I-Beta team really showed their stuff when they tracked this bad boy down and helped Mr. Heydon focus on killing it. It deserves a full definition, not only for historical purposes, but also in case it ever rears its ugly little head again.

The XYZ part of XYZ-HASA refers to the xyz position in space. In other words, if Cowboy 12 is an AI controlled aircraft flying right off your wingtip in formation, and you choose to dynamically re-enter it (that means enter it in mid-flight), then when you do dynamically re-enter that aircraft, the human should be put right in that craft at its current location right off your buddy's wingtip. Right?

Well.. unfortunately, since the original release, that was not what happened. As soon as the human was applied dynamically to that AI craft, that AI aircraft would literally warp anywhere from 4 to a million miles away. We started inventing terms like "warp -4" (back 4 miles) and "warp one million" (god knows where that one went .. hehehe). We even had a weird one we once called "warp RTB" (RTB = Return to Base).

That was a real weird one, because no matter where the aircraft was at the time you entered it, it would always warp straight back to the base it took off from and be placed on the ground in the grass field near the base of origin, with its wheels down !!! No kidding. We called it "Warp RTB" (RTB=Return to Base). So clearly, For this revolutionary new feature in Falcon 4.0 to be worth a damn (dynamic re-entry has never been done in a complex flight sim before.. not even SU-27 1.5), this feature needed a lot of work.

The HASA part of this term stands for "Heading/Altitude/Speed and Attitude." After all, even if the programmers got the XYZ position correct, what if the aircraft was suddenly turned around 180 degrees from its original direction (heading), pointing straight down at the ground (attitude), was in a stall at 80 knots (speed), and was suddenly only 500 feet off the ground (altitude , which is actually part of xyz, but you get the point here.) So it wasn't enough that we fixed XYZ. We needed to fix XYZ-HASA.

This bug took many failed attempts to fix, and is still not perfect yet, but has come 95% of the way there since this version. It works very well almost all the time now. Here is an inside explanation of what is happening, how it works, and what the remaining little problems are.

Click to continue

 

  When the Gilman pie (those 5 pictures we see during the loading of the game) is at the transition from Gilman Pie Slice 2 to Pie Slice 3, that is the point at which a player inside the simulation will see your name label applied to the aircraft you are entering. It is the time that you are actually placed in the aircraft. It used to be the time that the wild "Warps" occurred as well.

The problem is that even though you are now "applied" to the aircraft, you still have many seconds of load time remaining, and therefore cannot see the world around you and fly the aircraft. SNAFU you say? Well, not really. The solution is that at the moment you are applied at Gilman 2/3, the "Combat autopilot" is also activated. And at the very instant that you actually enter the airplane, a final XYZ-HASA packet is re-checked, the "Combat autopilot" subroutine is disengaged and whamo! You are in the hot seat. Sometimes it helps to understand the inner workings, don't you think?

And please don't be confused by this explanation. The user does not have to have "combat autopilot" selected in his setup for the program to use combat autopilot in this load "Dynamic Re-entry" situation/Gilman pie sequence. So just leave your autopilot settings anywhere you like it.

COTT

The document that defined this bug and its fixes was ten full pages in length. Here is the initial definition....

A set of bugs which have come to be cumulatively known as the "CHAOS ON THE TAXI-WAY" bugs (COTT) have been identified and characterized. All of them will be given names here at the beginning of this write up, and then defined through out the content of this write up.

The COTT bugs are a result of the following individual bugs.

1. The "Slider-Collider" bug (AKA the "Explosion on Entry" bug)

2. The "Variable destructibility of aircraft on the Taxi-way" feature

3. The "Over-Zealous 1-1 Aircraft AI brain" bug

4. The "Chain-Link, Who Follows Who on the Taxi-way" bug.

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