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(Starting stuff by Kawigi)

Some Notes about the timeline of a melee battle

David Alves's Stages to a melee battle (from the Melee page):

  1. 10 bots on field, bots in bad starting positions die right away. Hope you're not one of them.
  2. 6-7 bots on the field, fighting over corners and trying not to get pushed into crossfires
  3. 3-4 bots on field, everyone stays in their corners and snipes at each other. Try to get the other guys to target each other instead of you
  4. Duel

In reality, these stages aren't something you normally put into code when making a melee bot, they're observations about what a battle will look like between several very good melee bots. The fact that these stages are defined in terms of position and movement says alot about what is important in melee, but let me add my feelings about the importance of targeting in these stages:

  1. 10 bots on field - if there is someone close to you, it had better die before you. Most good bots will turn and move away from other bots or from the center in general right away, so if you have some kind of targeting that shoots at the path of least resistance, this is where you'll notice it, but a semi-linear targeting will probably work for that first few seconds in the match.
  2. 6-7 bots on the field, you'll be happier if you're targeting one bot and no bot is targeting you. You should be able to hit most of the bots you'd reasonably want to target at this point, and you won't be successful with a hit rate of less than maybe 25-30% at this point.
  3. 3-4 bots on the field, this is where you'll be the happiest with solid targeting. Here's why: when you're down to 4 bots, as David pointed out, there's a really good chance that you're all in corners. If the next bot who dies is the one across from you (the one you probably weren't targeting), you are probably next, because you're the most obvious target for both of the remaining enemies.
  4. Duel - I don't think I need to explain why targeting is important here. It's your gun against their movement.

The reason these stages are important to understand is really so that you can analyze your melee bot's performance. If you put it in a battle with other bots of a similar level (say half better and half worse, but all as close in ability as possible),

How to put together a good melee bot

As with any kind of new robot, the main thing that's useful when making a new melee robot is to have some kind of idea you want to try. It can be original or not, it can be a spin-off of what other people have done, or it could just be in general that you want to try making a melee bot.

Nowadays, most people have some experience with 1-on-1 bots before they go too deep into melee. In reality, melee is just like 1-on-1, except that there's something that supercedes 1-on-1 movement (which is moving in such a way as to not be hit often) - moving in such a way that you aren't being shot at!

The theory of melee movement

You'll dodge every bullet if no one is firing at you, and so most melee movement is centered in one way or another around not getting attacked. This is what makes melee movement so dang interesting. If it is inevitable that you will be targeted, then you can start worrying about just not being hit.

In discussions with (melee legend) ABC, I remember summarizing these two movement goals combine into the balance between "being in the right place" (not being shot at) and "moving in the right direction" (not being hit). Since you can only move in one direction, sometimes you have to choose to either mov toward the right place or move in the right direction. Since different bots prioritize these differently, some will be extremely predictable and easy to hit, but it doesn't matter until someone shoots at them. In fact, in theory, as long as no one is shooting at you, the only reason you really have to keep moving is to make sure they keep not shooting at you (until they're shooting at you again, which would be nice to be able to magically determine).

Common ways of implementing melee movement

There are lots of ways people accomplish the goals of not being targeted and not being hit. Some common examples:

AntiGravityMovement - In AI I've heard this generalized as using "repulsive fields". You could also combine it with attractive fields if you want, but there's rarely a real reason (same goes for tangential fields, for which there is a reason, but the actual implementation is hard to really get right in a pure anti-gravity force-vector sort of way). The basis of it is just like in physics - you define a set of points that have an antigravitational (repulsive) force on them, you add all the force vectors together, and you let them "push" you in whatever direction they push you in. Normally other bots and walls are assigned forces. Sometimes the center of the field has a generic force as well, or even the guessed positions of bullets. A classic example of AntiGravityMovement is TheArtOfWar. A simpler implementation is Graviton, but simpler in this case doesn't necessarily mean more clear (same goes for Escape, which is a more convoluted bot based on Graviton). Hanji's page has a very stereotypical, very clear implementation of antigravity which might be helpful if you are trying to get into it. The biggest challenge in getting AntiGravityMovement right is weighting all the forces effectively, especially when there are more or fewer points on the field (maybe the walls have to push harder when there are more bots on the field pushing you toward them?).

CornerMovement - In the early days of Robocode, one of the frustrating things about trying to excel in melee was that the bots that seemed to do the best in battle did stupid little patterns in the corners of the battlefield. This came from the general observation that the bots that lasted to be one of the last standing were the ones that got to the corners the fastest. While this isn't really always true, there are probably fewer bots near you in a corner than in the middle, so the technique works - just go to the nearest corner, keep moving, and kill anything that's trying to take your corner from you. I experienced frustration with this movement when I would watch SandboxLump with his stupidly simple movement kill Coriantumr in so many of my tests. Out of my frustration came Lib, the most complex CornerMovement ever put into a NanoBot (I assume that's still true, it at least was at the time). Traditionally, using CornerMovement will make you specialized as a melee bot, because it tends to work better against the best melee bots than against mediocre ones.

Moving in a small, simple pattern (for lack of a better name for it) - Alot of quite good nano melee bots just dance around in a star shape, or triangle or square. Some of these go in a straight line for awhile first (until they hit a wall or something), so it's closer to a type of corner movement than anything. The virtue of this movement is that you don't move around too much, so you are less likely to have new bots start targeting you because you move into their range, and it does well against the horde of melee nanos with something related to linear or circular targeting (because you change directions relatively often). Gem, Infinity, KomoriNinja? and Trigon are good examples of this movement.

MinimumRiskMovement - On the surface, this looks like just an implementation of AntiGravityMovement, and maybe the difference is just nitpicky semantics to some, but I think the way it is implemented is different enough that the only similarity is really the basic fundamentals of melee movement. It also seems much more versatile than AntiGravityMovement and is also less likely to converge at some "happy" local minimum. As I am biased, I think that the best, clearest implementation of MinimumRiskMovement is in Coriantumr and Shiz, although HawkOnFire's implementation is also available now and it is just as effective and maybe slightly more basic. There are two basic parts to MinimumRiskMovement:

Then you just go to the candidate point with the lowest risk (or highest benefit, although MaximumBenefitMovement probably has more place in Teams). Randomness can assist in either function just as effectively. Also, as an interesting tweak, you need to decide to look for a point to go to constantly rather than only when you reach the last point you were going to. Both strategies have merits - you might get into a rut if you keep changing your mind on points, but you can also more quickly react to changes in the battlefield.

OneOnOne Movement - If your bot is good at close combat, you might consider chasing one robot at a time with that movement. Chances are that if you are close to one robot, you're far from others (because who's going to go running towards two other robots?) DoctorBob is very successful in this, and it's also one of the reasons Tracker doesn't do too bad in a battlefield full of sample bots at least.

Things to think about in your movement

Here are a few things that you should consider with your movement, whichever type of implementation you pick:

Being far away from other bots
This one of the easier things to test for, of course, once bots are so far away, it doesn't matter as much if they get further. That's why using the inverse square of the distance to each robot works so well (the threat approaches zero at some point). This will likely keep you out of the action.

Moving perpendicularly (one-on-one-like?) to other bots
Especially bots that are close to you.

Don't hit walls or other bots (too much)
It might be tempting ;-) This is possibly a bigger deal in melee, just because you're going to be close to other bots and to the walls alot more than in one-on-one.

Stay out of the middle
People always say this, but in reality it's ok to be in the middle if the battle is still big and all the other bots are on the outside. However, if you're still in the middle with 4 or 5 bots left, you won't likely last long.

Don't stay in the same place for too long
Just as in 1-on-1, this can be quick death. I don't care how great that spot is, someone will get close enough to it to put you in danger in not too much time.

Guess who is/would fire at you

Note - This is a little more advanced of a topic in melee movement, and it's a little hard to explain clearly, but it's also not impossibly hard to implement. It's also the main secret of the movement in Coriantumr and Shiz. FloodHT does it as well, but its point-generating function is bad, so it doesn't really matter :-p I'm not sure if anyone has really tried too hard to do this before.

Looking at the list of ways one could pick a target, the one you have the most potential control over is whether you're the closest target for any other bot. If I want to pick which point is the best one to be at, a big part of that is counting for each bot how many other bots are closer to them than me. If 0 or 1 bot is closer to that robot than it is to me, that means it's likely to be aiming at me. Combine that with the possible knowledge that that bot has hit you recently, or that you're shooting at that robot, you have a pretty good guess as to whether that bot is likely to be firing at you if you were (or are) at that point.

There are at least two applications of this information:

  1. You want to be at the point where the fewest robots will target you.
  2. You only have to worry about being hard to hit to the robots that are likely to target you (in other words, the direction you move in to get to a given point only matters relative to bots that are likely to target either that point or your current location).

Battle Dynamics change constantly
Be capable of adjusting and changing quickly, and don't try to plan too far into the future.

Little melee tweaking notes

A few things that might just get you up a few spots in the rankings:

Melee Radar

What you do with your radar really depends on what your targeting strategy is, and whether or not you want to fire blind (firing blind means you don't fire when you can actually see your enemy, but rather in your general run loop or something). If you just spin your radar constantly, you almost need to fire blind, otherwise your gun won't have time to turn before you fire. However, I find (again, if your gun doesn't depend on a spinning radar, like some melee pattern-matchers do) that firing blind reduces my hit rate by a little. I suggest (particularly if you're using a guess-factor gun in melee) using a melee radar lock, which is a trick I learned from PaulEvans? (so it must work!) A melee radar lock is spinning your radar until you're getting close to firing, and then lock on your target as if they were the only bot on the field for a couple ticks until you fire. Plus, if you have a radar lock in your code, you can also use it for one-on-one :-)

Melee Firepower

Alot of hitting happens early in a melee match, but by the end you can be pretty well drained of energy. Some people take the survivalistic element of melee to mean they should always fire low-powered bullets. This is only partly true - you will likely start the melee battle close to other bots. So close, in fact, that you are very likely rack up alot of hits (either for or against you) in the first 5 seconds of a match. Don't be shy about firing bullets that are more than powerful enough to finish a bot off if they're really close to you (because you still want to finish them off if they hit you or someone else before your bullet reaches them, and if you're REALLY close, that's likely to happen). I've seen some smaller melee bots (I think Graviton and Troodon were two of them) that even multiply their firepower by getOthers(). I also think that you shouldn't make the mistake of having too "merciful" of firepower in the final stages of the battle (meaning you should be aiming to kill when you're shooting at a low-energy target at any point of the battle).

Picking a Target

There are so many heuristics that can be dreamed up for this, but one of the easiest and most effective is to simply target the closest enemy. While this is the best general guideline, it might be beneficial to take a few other things into consideration:

Enemy Management

If you're trying to convert a 1-on-1 bot to a melee bot, you'll find out quickly that all the little assumptions you used to make when you coded your 1-on-1 bot are wrong. It can be a big challenge to effectively store volatile information about your enemy (like current position, heading, velocity, etc) as well as persistent information about your enemy (like targeting information). One of the big challenges is how to specify that a given enemy is dead. I stumbled on a great way to do this when I was working on Coriantumr, which was to have an volatile object (class EnemyInfo) in a Map that has position, heading, velocity, and all the obvious stuff in it, as well as a list of waves (note - all these things should go away between rounds). This map doesn't have to be static (although it probably is for codesize reasons), because it's recreated every round. In onScannedRobot, I check to see if the robot I'm scanning is in the map, and if it isn't, I put it in there. Then I get the EnemyInfo object and operate on it all over onScannedRobot. onRobotDeath? removes that robot's object from the map if they exist (so the robot no longer exists when I don't care about it anymore). Meanwhile, I have a different map which maps the name to the guess factor stats which is static and isn't reinitialized between rounds.

Targeting algorithms in melee

Lots of things can work well in melee:

HeadOnTargeting in melee

Always a good place to start. On a related note, I've heard of melee targeting which targets the rolling average of the robot's position, since it is common for a robot to stay near the same place for awhile. Not sure how this really compares in general to just firing right at the target.

LinearTargeting/CircularTargeting and variants

You can go far with some kind of percent-of-linear targeting, or using circular targeting in melee. It has been observed that if you are close to an enemy, you have really good odds firing with linear targeting, and if they're further away (say moving around in a corner or something), you have pretty good odds with head-on or somewhere near that. Take a look at Infinity for a really elegant solution to this observation. Another thing that might work well is velocity-averaging. Some more observations could certainly be collected to create a generally good melee gun that is simple to understand and code and is *very* resiliant to missed scans.

PatternMatching in melee

Be careful to make your targeting algorithm resistant to not having constant scans. If you spin your radar, you will get a scan on a given robot every 8 ticks on average. Occasionally (ok, actually somewhat often), you'll scan a bot two ticks in a row, and that should throw your targeting off. Often, you'll scan the robot again after 7 or 9 ticks. If your targeting algorithm absolutely requires scans every 8 ticks, you'll have to make it realize that the world isn't perfect. In my opinion, pattern-matching has been slowly becoming obselete in one-on-one in its purest form (note that there are ways of making it last in the realm of random movement), but is still definitely alive and kicking in the melee world, if only because melee isn't as well developed.

GuessFactorTargeting in melee

FloodMini from the start has had a wave implementation that was really good about missed scans, mainly because its radar was far from perfect. The same idea is in Coriantumr's gun, which is to interpolate missed scans linearly and check at each interpolated position/time if the wave hits. This is probably the trickies part, along with how to store the waves (see the Enemy Management section above). In general in melee, you're pretty safe firing a wave on every scan of a robot, not just when you fire at them, but realize that robots might be moving different relatively to you if you're not shooting at them (or likely to shoot at them anwyays). Segmenting on distance and possibly battle size can help compensate for this problem, as well as segmenting on lateral direction (are they moving roughly perpendicular to you, toward you, or away from you?) Acceleration segmentation can be a little harder to do in melee, since you aren't getting consecutive scans for all of your waves, but I've observed that if the sign of the enemy's velocity is opposite of the previous scan, they're probably accelerating (unless they are already at velocity 8).

Also, I recommend using a melee radar lock for GuessFactorTargeting (see Melee Radar above).

For any of these techniques, you should consider making sure you don't fire off the battlefield at a or in a direction that can't possibly be reached by your target. This sounds obvious, but I don't know how many times I've seen a robot aiming at another robot that was moving toward a wall, and the shooting robot just shot right into the wall, which is a complete waste of a shot. This is one of the improvements I made in Coriantumr from 1.0 to 1.1.

Evaluating your Melee bot

Before I get too far into this, I want to emphasize that the number one way of figuring out where you can improve is by critically watching the battles. But, there are some other useful things you can do that might take a little less time once you get more refined:

//global declarations:
static int[] finishes;
//beginning of run():
if (finishes == null)
	finishes = new int[getOthers()+1];
public void onWin(WinEvent e){onDeath(null);}
public void onDeath(DeathEvent e)
	for (int i=0; i<finishes.length; i++)
		out.print(finishes[i] + " ");
This will print out a list of wins, 2nd places, 3rd places, etc. at the end of each match. Obviously, you want to maximize the wins ;-) Of course, what you want to do first is make sure this gives a regular, smooth distribution over time. You can analyze where some of your weaknesses (relative to the stages to a melee battle at the top) by where the highest numbers are. For instance: The first stages might be more important score-wise than the last ones, at least at first.

I think we should add a few tutorials or in-depth descriptions of a few good melee bots (especially the open-source flavor). Maybe a few pages like: These can be filled in by the authors or anyone else who has taken time to understand them (or feel free to describe your own).
Watch this space for more! -- Kawigi

Megathanks for making this page Kawigi! Good reading. I'm not sure I agree I wouldn't put the different stages into code. Some of the ChironexFleckeri versions did that even. CF also segments it's movement and targeting stats on this. Even if the latest version only separates the melee stages from the duel one. But that's mostly a codesize issue. It seems CF is using MinimumRiskMovement as you describe it. Though I think that name is too general. I would say WaveSurfing is minimum-risk too. -- PEZ

Indeed very good reading. A real melee-movement (read: AntiGravityMovement or MinimumRiskMovement) goes up to #3 on my prioritylist, a one-on-one PM-gun just has to wait a little longer. -- GrubbmGait

I definitely think that WaveSurfing is a simulation-involved form of MinimumRiskMovement, in fact, I've even tried (unsuccessfully, but I think I know what my mistakes were) to implement a flattening movement with minimum-risk concepts. As for not coding the different stages, I'm specifically referring to movement - I would encourage targeting based on those phases, because segmentations are all about the observation of different movement patterns in your enemy. Since robots who weren't even coded to care how big the battle is move differently with 4 robots than with 8, it's very reasonable to segment on that. As far as coding it in movement, I think that's dangerous, mostly because it can unnecessarily specialize your bot. I think I remember David Alves saying that he preferred using fluid functions to if statements if he could help it, and this is a good example - if you have a risk function that you want to emphasize some feature more when you have more bots, you can put getOthers() into the function, or if it's something that isn't relative to specific bots, you can make it not scale to getOthers() (what I mean is that if your risk function has a part that involves iterating enemies and a part that doesn't, if you don't multiply the part that doesn't by getOthers(), it will automatically have more bearing with fewer bots on the field, because the total numbers will be smaller). -- Kawigi

I totally understand what David means by fluid functions rather than if statements. I think many of my bots are extremes of that. Aristocles, Pugilist and CassiusClay all have very little of conditionals and work without special cases as much as they can. However, optimal melee behaviour between 10 and 4 bots might not represent a fluid change of state. I say "might" since I have very little experience with this. -- PEZ

I guess that I'm more of the opinion that a fundamentally sound movement implementation will act optimally (albeit differently) in these very different cases, because the goals are primarily the same. Added a few more sections. -- Kawigi

Again thanks! This is a candidate for the "best Robowiki page ever" title. -- PEZ

You're welcome. Added a bit more content (can you tell I'm having trouble focusing on work?). -- Kawigi

Quote: 'Add any other tips that seem to work for you ' End Quote.
What other tips, are there any tips left somewhere. This is the most informative page I have seen sofar. Although most information can be found elsewhere scattered on this wiki, this is the best concentration of useful information I've seen. It feels like I have still to write my first melee-bot. You have my vote. -- GrubbmGait

Oh, there are plenty more development tests which can be applied to melee, I'm sure I haven't exhausted them all (or even remembered all of the ones I've used). Also, is there some place where you're voting for best pages? I think if this is one of the best pages, it's because (at least when I started trying to do it) there just is a lack of information about melee here. There's a few people who are really good at it, but not alot of idea-sharing and implementation sharing. In fact, before I released Coriantumr and Shiz, I think Nimrod and TheArtOfWar were the only top-10 melee bots that were even open-source (and I think most people are a little intimidated trying to read TheArtOfWar's code, simply because of it's mass and complexity). So I guess this is a tribute to the black hole and the prying I did to get information out of the top melee guys when I was newer to it. -- Kawigi

A real pleasure to read this page. -- rozu

Indeed. It's not only because melee info was so scarce before. This page is so well written and composed too. You should consider a writer's career Kawigi. =) -- PEZ

Well, I do think I write clearly (and not all of this is easy to explain!), and an extra read over the more complicated parts usually reveals a better way to explain something. While clear writing is a forte, however, conciseness isn't, so if I get to really trying to explain something (example: the old FloodHT hype page), you should expect to read something long, clear, and often full of rambling and rants. I think that both my clarity and verbosity are partly a result of being an educated native English-speaker (in "programming" circles, this isn't critical, but some people do still have trouble expressing themselves effectively in English. That's why we don't have a big clear disertation like this on what "Wave" pattern-matching is - I'm almost positive Iiley has written one in Chinese on his site, though).

Another thing I've sacrificed for the sake of clarity and organization is order - some of you read this all the way through the first time I posted it, and I've added things to it since then, not necessarily at the end. The diff functionality of the wiki helps reduce the disadvantages of this, though :-) At any rate, I think that this page has stablized a bit, and the last set of links I added will be what really makes it more in-depth. -- Kawigi

I don't think there is such a thing as Wave-PM. Unless the mega-failure Resin counts. =) -- PEZ

That's because semantically, you think of any gun for which the shot bearing is calculated from a wave as statistical. Iiley didn't think that way (and I agree with him on this). His gun was very much a pattern matcher (just as much as NanoLauLectrik's gun) - It matched a single pattern. It wasn't a pattern projector - the way it actually calculated the bearing to fire at was unrelated to the pattern, it was the bearing of a wave fired at the point in time of the end of that pattern. -- Kawigi

No, I don't, sementically, think of any gun using waves for shot bearings as statistical. Resin should prove this. And Ali/BumbleBee uses a very Cigaret like gun. Very similar actually. (Though that's a coincident if there ever were one.) It's still statistical. As is Cigaret's. In theory you could take any PM gun and use GFs for projection instead of pattern-replay. It would still be a PM gun. If Cigaret's gun is a PM gun then so are all my Tityus derived guns and FloodMini's too. The only difference is that FloodMini stores the segmented data for much faster access. Look at how the latest version of ChironexFleckeri stores its GF's and you will see a gun that could be tweaked to act exactly like Cigaret's only order of magnitudes faster.All Cigaret is doing is asking "what GF did the enemy end up at last tick that looked like this one?". That's what CFis asking too. FloodMini makes it "ticks" (plural) and uses the most common answer. Where, going from FloodMini to Cigaret, does things turn PM? But hey, remove this babbling! It's now cluttering your excellent melee strategy page. =) -- PEZ

Where, going from FloodMini to Cigaret, does things turn PM? - at the point where it's storing the last 3500 ticks of arbitrary information (plus whatever has been collected this round) and comparing each consecutive group of 72 ticks with the last 72 ticks to find the closest match, it turns into a PM (actually, it looks like he compares every 6th tick back 12 times, probably for performance reasons). Note: Feel free to move this to another, more appropriate page :-) -- Kawigi

I think the important difference between PM and Statist is the sorting. Pure PM sort every pattern to a single unique pattern, and Statist sort all patterns to be a certain number of kind(That's the segments). So in PM, there is not probability or factor, but statist is, PM search the closest match but Statist search the big probability(factor). So in this case, Cigaret's gun are pure PM. FloodMini's are pure statistical. Some combine way search the certain number of closest matchs and then segment it to count the factors was both PM and Statistical(maybe that was how Shadow gun does).

Well now, friends, very excited seen that you are focus into melee, and this is a cool page, Kawigi, great down. Maybe more melee discussing will be added on. The last version of BlestPain i tried to add the Lacrimas 1v1 movement strategy to melee, so BlestPain becamed a melee bot. But it did not good. I's hard to write a good melee movement. But when i saw PEZ and some other robocode friends are try to implement WaveSurfing in melee, i am waiting and see, I am cowered, when i was impelmenting Pear, i plan to implement WaveSurfing melee movement in it, but you know Pear's 1v1 was not enough good yet. Well however, maybe i will have a try.~:] -- iiley

Yeah, I think I knew that BlestPain was trying to do WaveSurfing in melee. It's not a bad thought, really, but it has two downfalls:

That's not to say it won't work, though.

I hope the net effect of this page is that more discussion, development and general competition will happen in melee. -- Kawigi

Yup, i don't quite know who's aiming at me in the first place, so i can't think of every one are aiming me, i assume every robot target the closest enemy, then i just surf one bot's bullets. So there is not many dang bullets, but it is not very precision but most robots are targeting ther closest enemy in rumble. However, BlestPain are not real a sufer, it's Lacrimas's dodge movement, so it did not very good. If i want to improve it, i should base on Pear, but Pear's movement can hardly turn to melee, months ago, I'm think of just dodge enemy's bullet(The Highest of Factors) by Anti-Gravity, it must be easy to implemented than sufering(Many bullet may be easy to dodge than many Waves). -- iiley

Early in the development of Ugluk I noticed that he was doing well in melee. His movement was not complicated either.. it was basically going top speed with a slight weave and bouncing of walls at 45 degrees. While he didn't favor corners or avoid the center of the map, he lived quite a while because in order to remain a favorable target his enemies would have to chase him at top speed like a ram bot, which isn't a popular movement style. It also means he would present himself as a target option to other robots as he went on his way, but with infrequent full circle radar sweeps by the enemy Ugluk had a low chance of being chosen as the most favored target at any point. While the movement has been overhauled a few times, I try to give Ugluk an opportunity to shake pursuers in melee while not actively finishing off an opponent. --Martin Alan Pedersen

I was thinking of making a GrudgeBot, a bot that holds a grudge against the first bot it sees in a melee battle and proceeds every round there after to go after that same bot, ignoring all the others (cept for movement of course) till the bot it has a grudge against is gone. I was gonna do this for the sheer evil of it, but at the same time the bot wouldn't be much of a contender, but instead be a bot that drags down all the other bots. (Sorry i'm having one of those mornings where you just wanna make something truely evil) -- Chase-san

How do you make a bot that's shooting at you shoot at another bot (besides moving away from the shooting bot)? --Starrynte

A lot of bots just target the closest bot, so making another bot the closest would be one way. Some bots take energy into account, so shooting at another bot close to it might make it target that one. Really, though, there's only so much you can do... (You could also just try to kill that bot. =))-- Voidious

My latest melee movement is a pretty sound minimum risk implementation. One thing I am observing is that it is pretty weak in the very beginning. If you look at a melee round by how many opponents are left at the time, there is a large portion of it spent with 9 opponents. If your movement can't handle the opening of the round, you are going to get eliminated much more than your share. Right now in testing against the 9 best author's best bots, I am getting more than my share of Last Man Standing, but I am also getting killed first twice as much as the average. I may introduce a new opening movement and then switch after the first person dies. (I've broken it down even further in the past, but with duel style movements.) -- Martin

MeleePatternMatcher doesn't seem to work yet. Any ideas? (post on MeleePatternMatching page) --Starrynte

Right now, Smash is thrashing between enemies a little too much. Does anyone know how to fix? (code is posted at Starrynte/Smash) --Starrynte

There are two good ways to prevent this that I've seen. The first is not to switch targets unless your previous target dies or is at least 10% (for example) more desireable than the current target. In practice, this usually means until someone else is 10% closer to you than your previous target. The other way (which I believe Coriantumr does, but I can't remember for sure) is to realize that it only matters if you thrash too much if you do it right before you were going to fire - so only switch targets if your gun won't cool for another 4 or 5 turns. -- Kawigi

Ok...thnx Kawigi --Starrynte

Though I was not around for this, I have read about the timeframe that Cynical was released, which had a very hard to hit (at the time) movement style, and didn't bother to fire. He'd win battles through attrition, presumably prompting the introduction of points awarded for bullet damage to discourage the mockery. So the present assumption is that you need to actively attempt to damage your opponents to compete effectively. I am now wondering if that applies in Melee. In the early stages of the battle you definitely need to lay out as much damage as you can, because your opponents have less room to move and even misses are still likely to hit someone else. But later on, as the Last Man Standing bonus of 90 points is in sight, it may be time to be very conservative with your shots. Just a thought. -- Martin

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Last edited January 7, 2008 17:18 EST by Martin Alan Pedersen (diff)