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Author Topic: Is the firestorm and lighting elerium design flaw bug fixed?  (Read 10404 times)

Offline Arthanor

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Re: Is the firestorm and lighting elerium design flaw bug fixed?
« Reply #15 on: August 15, 2014, 07:34:50 pm »
Indeed, multiple waypoints would be good (especially if the last one can be a UFO to intercept).

I've found that playing "flight controller" for my fighters is not so bad. It makes the geoscape "battles" more engaging than just "launch interceptor". Maybe it is a good thing that they don't use the best interception route after all..! It leaves me with something to do while waiting for the dogfight.

Speaking of dogfights, I seem to remember UFOs spreading their fire in the original, if engaged by multiple crafts. In OpenXCom, it seems like the first fighter to get in range gets the full attention of the UFO (which is dangerous, but also means you can "exploit" it by having your stronger crafts tank while weak interceptors get to shoot with impunity)

Offline Hobbes

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Re: Is the firestorm and lighting elerium design flaw bug fixed?
« Reply #16 on: August 16, 2014, 02:35:54 am »
Yeah... The route a skyranger uses to get to a terror site is much improved, indeed. But that's not much of an issue.

The route an interceptor uses to get to a moving UFO? A Great circle is better than whatever way they used to take before, but going towards the UFO's current location is still a very bad interception mechanism. Using the heading and speed of an UFO, which are already provided by radars, to guide it would be much better.

But isn't this a lot more complicated? To get such a vector for an interceptor you need to use the heading and speed of the UFO plus a time window. Or, "send the interceptor on a course that it will intercept the UFO in 2 hours if it keeps its current heading and speed". But this time window can vary greatly. I.e., launching an interceptor from North America against a UFO in South America will take longer for it to arrive, than if the UFO is located at North America.

Or you could simply set the time window for 30 minutes but then you risk that the interceptor is constantly correcting its path if the UFO arrives at its location and its trajectory implies a lot of turns. And in that case it would seem that manually picking a location might be more effective.

Offline NeoWorm

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Re: Is the firestorm and lighting elerium design flaw bug fixed?
« Reply #17 on: August 16, 2014, 11:35:27 am »
To get such a vector for an interceptor you need to use the heading and speed of the UFO plus a time window. Or, "send the interceptor on a course that it will intercept the UFO in 2 hours if it keeps its current heading and speed". But this time window can vary greatly. I.e., launching an interceptor from North America against a UFO in South America will take longer for it to arrive, than if the UFO is located at North America.
Hey, mathematics people. Time is one of the unknown variables that you need to calculate. So any discusion about time window in which the predictions will be made is pointless. You can calculate the meeting point anytime you wan't independent on distance or time. Or to calculate that you just cant catch the UFO.

But such predictions can lead to some weird stuff going on when the UFO is far away and flying fast. It can happen that if UFO is speeding away from you, by the calculations it can be more effective to go around the world and meet the UFO head on. But when the UFO changes speed or direction, you can suddenly be stranded on the other side of the globe without any chance to intercept.

So to make the interceptions effective you don't need time window in which predictions would be made, but more practical is a distance under which your interceptors will try to predict UFO path. And this distance can be either fixed, depending on craft's speed or just variable that player can set.

Offline Arthanor

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Re: Is the firestorm and lighting elerium design flaw bug fixed?
« Reply #18 on: August 16, 2014, 03:55:55 pm »
Indeed, there are already very sophisticated algorithms to calculate interception courses. At the basic level, it's just finding the point where two lines (UFO and Interceptor Trajectories)cross, varying the heading of your Interceptor but considering its speed at constant max speed. You then update that every so often (the current course is updated every time the UFO moves, so updating is not an issue). Then you can get into more complex algorithms or also define "regions of interception" (like if you have a HWD, force the interception to occur in the region you know the UFO is running its mission).

All that being said, I no longer think it is necessary, or even favorable, to have that, since it gives you an extra role in the geoscape: Flight Controller, instead of just watching your interceptors and waiting because you know they are also using the mathematically best way to intercept. Having a bad automatic intercept makes the player useful.

Multiple waypoints (assigned on a shift-click, like in most RTS?) would be awesome though, especially if the last can be an UFO.