Developer diary #12

[Slaughter]

The next intallment of the UFO:Aftermath developer diary is here. Just click "view comments", and you can read it. It will be added to the other diaries soon, but due to some trouble, that will have to wait.

 

Update: The latest developer diary have been added to the others, and can be viewed here. Enjoy!

[Slaughter]

Developer's diary: Part XII

 

(June 31, 2003)

 

Greetings, my dear friend, and friend of these diaries. We have rounded the first dozen and our story is slowly drawing to a close. The crunch time is upon us and the glimmer of gold disc can be seen not far away... But enough of this poetic verbiage. Last time I promised I would write more about the way the game works and now it is the time to deliver.

 

While the tactical gameplay is pretty much set for some time now and we are now balancing weapons stats and strength of enemies, the strategic game was in very much rudimentary state. Now, our strategic game is the less complex part of the game, yet still it is more than a mere engine for tactical mission generation. We always wanted the strategic game to be a game in it own right, it should be able to stand up on its own. UFO: Aftermath should be interesting even if you could win a tactical mission by a mere click of a button.

 

If you follow the development of UFO: Aftermath for some time, you know that the strategy game - that's the part with the spinning globe, flying UFOs and various markers - revolves around the territorial expansion. The principle is very simple: there are some flashpoints on the border between yours and enemy's territory. A successful mission there could tip the balance of power and deliver you a large stretch of territory (or you could lose a large stretch of your territory by losing or ignoring it). At any one time, there are several possible missions (about five or ten) and you must decide which one you shall commit your squad to. When you select a mission, a chopper flies from one of your bases, carrying your men to the spot. Then you play a tactical mission, win or lose, and then the chopper lifts you back. Each mission is active only for a limited period of time; if you ignore it, other human troops will take care of it and your squad will not be involved

 

A successful tactical mission will increase your influence over territory, while the alien victory will increase their influence. Obviously, the interesting question here is the exact way this is implemented. For generation of the missions we use a sort of an abstract "influence" field both for the player and the aliens. We then combine these fields to find places where there is the greatest "tension" between the two - these are the spots where the next mission is most likely to appear. When we know where the mission is we determine its weight, or importance. We take into account the distance from the player's territory, its difficulty and some other things. This is then how much impact this mission will make.

 

How do we interpret this impact? This is going to be a subtle point and I am including it here because I believe it can illustrate the nature of choices a developer is making when designing the game. The bases on the globe divide its surface into areas or spheres of influence. We use a Voronoi diagrams to generate them, so each base controls all the territory that's closer to it than to any other base. As a result, the areas of each base are vastly different, depending on their distance. The largest territory by far belongs to the base on the Easter Island. Now should the influence of mission depend on the size of the territory or on its distance to the nearest base? Imagine two otherwise equal missions, one taking place in Europe and other one in Africa. Should the first make bigger impact (it is closer to a base), lower impact (it is in a smaller territory) or should it be equal? And how many territories should be influenced - only the one where it takes place or also the neighboring ones?

 

In the end we decided to put the game before realism, so in the example above their impact would be equal. It is slightly illogical that a victory in a mission can have the same influence over a base several hundred kilometers away as it does over a base just next to it. On the other hand a base in a bigger territory is not more important - it does not have better aircrafts, provide more research or manufacturing. So it is only fair that it conquering it is as simple, or as difficult, as conquering a base in a more densely populated area.

 

We also decided that the outcome of a mission should influence other territories beside the one it is taking place in, albeit much less. Again, this influence does not depend on the actual distance from the mission to a base. The size of territory therefore does not play any role in the game. You have to realize that the player does not see the bases he does not own and therefore he has no way of knowing how big is the territory he tries to capture. In this way it is much more predictable what will be the effect of a mission and predictability is the basic prerequisite of any strategy.

 

Another element of the strategic game which underwent significant development are the dogfights, or interceptions as the old fans call them. Originally, we thought the interceptions will simply be automatic - when an alien craft is spotted a military aircraft will take off from the nearest military base and try to engage it. However, feedback from the players and our own experience have induced us to include more gameplay here. So now, when an UFO is spotted, the player is asked whether he wants to launch an interception. If he does, a military jet will pursue the UFO and when the two meet, the dogfight starts.

 

There appears a window in the center of the screen: in the right you can see a short video, on the left you see outlines of both yours and enemy crafts. When a plane is hit it turns red (damaged) or gray (downed). At any moment, the player can click the Retreat button to salvage what is left from his aircrafts. When the damaged aircrafts return to their base, they must be repaired and while the repairs are under progress, that base cannot launch any interceptions.

 

This again is certainly not the most realistic simulation of aircombat, however it adds to the player's feeling of involvement with the game. The dogfights moreover relate directly to the tactical missions: if the player is successful, it may become possible to explore the UFO wreck and recover various important artifacts and equipment. If, on the other hand, the player loses, the pilots can manage to bail out and it is then necessary to rescue them.

 

So how do we measure up against the goals outlined above? Quite well, I believe. The strategic game is not the most complex undertaking you have ever seen on your computer screen, however it is engaging and easy to understand. Next time, I shall write more about the changes we made to the tactical game.

 

Martin Klima

ALTAR interactive

[samsmithnz]

Its good that they listened to the fans!!! If only more games had this sort of design interaction with the fans!!!!

[Slaughter]

Amen to that samsmithnz! ALTAR have been great to us, and now I hope they get paid for it!

[J.R.]

Please Slaughter, there is a mistake in name of the EASTER island, could you change it? Thanks to you and the one who found it (I lost his name).

[Slaughter]

So it's supposed to be Easter island? Fixed.