I''ve started on programming another game (my last which I actually sort of finished was a card game), and this time it''s going to be a "shoot-em up". If anyone remembers the old game Raptor: Call of the Shadows, it will be similar to it. As I''ve more intruiged by programming it the actual game content will not be of as high quality, however I do got a design question for you that concerns enemy reactions and intelligence. In Raptor, as well as in other shoot-em ups I''ve seen, enemies are fairly unintelligent. This is not a necessarily bad thing; enemies that always fly the same path add a need to learn missions in a game, and replaying the game several times can become fun for that reason. The most intelligent enemies in Raptor were the bosses and turrets which actually fired in your direction... Now I could program more intelligent enemies (even easier than pathed ones actually), but would these add anything to the game? It means a player can''t learn a map/mission in the same way. If enemies are more intelligent it might also reduce the "hero factor", as it would take less amounts of enemies to destroy the player''s aircraft. What do you think?

I liked the old pathed enemies. I know its out of date now but if your doing the programming for your pleasure I don''t think it matters at all. I worked on an arcade conversion of a 2d shot-em-up many years ago and the lead coder implemented a system where the same enemies always appeared in the same place but the exact spawn altered depending on your on-screen position. If you pulled back to top/left they spawned at the front bottom/right but if you tried to get the jump on them by positioning yourself front bottom/right to wipe them out then they spawned from the back top/left.

The screen was divided into quarters. Whichever one you were in, they spawned in the oposite. You could still get in a good position to wipe them all out but you couldn''t sit right on the spawn point with autofire on and wipe them out.

Dan Marchant
Obscure Productions (www.obscure.co.uk)
Game Development & Design consultant

I'm actually programming 2D-shooter too, and i choose path for the most ennemies, and a very small IA for the others (some fire or fly in your direction).
I find the "oldschool" shooters more fun, that's the reason I didn't choose intelligent ennemies.

screenshots:
http://seb.sevilla.free.fr/explode/screenshot1.jpg
http://seb.sevilla.free.fr/explode/screenshot2.jpg

binary (win):
http://seb.sevilla.free.fr/explode/explode050.zip


------------------------
- Seby -
www.dfhi-bomber.fr.st

[edited by - theSeby on December 1, 2003 6:57:11 AM]

Nice screnshots there! I''ll download that .zip when I get home and try it.

Yes. However, if I do decide to make more intelligent enemies, I can always make attack formations/patterns, which will allow the player to recognize some enemies anyway and plan combat strategies accordingly. Still I think the pathed method is better.

If some clever AI is implemented it would make the game more challenging, say you had a heat seeker and fired it at a ship, then it tried to dodge it, that would make the game more exciting than if they all follow a set path.

What about making "drone" type enemies (pathed) but make bosses with some AI, that would be a good balance of the 2 and make for some interesting gameplay.

Maybe say fighting a boss in an asteroid field, the boss could use asteroids as cover etc.

On the other hand, how about deliberately stupid? For example, they make an effort to fly INTO your bullets. Or they simply veer away from your ship.

Raptor had those "stupid" enemies too. Or rather suicidal as I should call them. They flew in lines straight into the player at high speeds.

Yeah, Raptor was one of those games with massively long levels (it seemed like it at the age of 12). I remember a game called ''Highway Hunter'', it was also on the same premise but you were in a high tech vehicle.

I personally like pathed enemies, but a combination would be interesting. I remember playing one game as a kid that the enemies stayed in your general area for a certain duration when firing (then went for you) and others that just randomly sprayed while going out kamikaze style.

I agree, I like the old school enemies that are either pathed or not terribly intelligent.

But. I think a good AI would make the bosses much more interesting. Bosses are traditionally just massive HP creatures that move in a circle, maybe flailing/shooting on a regular basis. Kind of amazing they could be in charge of anything. (but, given the average intelligence of their minions... ;-))

A weaker but smarter boss would be more of a challenge, and not automatically be a quarter hog.

I suggest that instead of choosing one type, put them all in. You could have mostly stupid enemies that just fly on a path off the screen in the early levels, with only a few instelligent enemies that stay around on screen until they die, and near the end of the game you could have mostly intelligent enemies and only a few pre-pathed enemies. Then, you could make the boss ships for each level use the intelligent AI and make them regular-sized ships so they can actually make use of it (rather than taking up half the screen and being impossible to miss).

That way you have more ways to vary the difficulty and the early levels can be entirely memorized but the later levels require some reaction. You could also use the quadrant system mentioned by Obscure to give even the pre-pathed ships a little bit of surprise even after you've played level 1 a few hundred times.

[edited by - extrarius on December 1, 2003 4:05:26 PM]