Quick Tutorial: How to Execute a Proper Cavalry Charge in EBII

[HaHawk]

Tutorial Link:

https://www.youtube.com/watch?v=J0mi8rUs240

I often notice that "bugged cavalry charges" is a common complaint here, especially by people who played the original EB on the RTW engine. I think the main issue is that people are not used to the mechanics of EBII, which uses the M2TW engine.


The original Rome has slightly more "arcade mechanics" than M2TW, and it is common to just issue attack orders with very little planning (Stop! No, go! No, don't go, stop! Now attack, attack NOW! Click, click, click). In contrast, M2TW requires us to be slightly more methodical and patient with our decisions (Plan, set waypoints, issue the order, and WAIT for the result). Thankfully, this is the perfect mechanic for EBII's battles, which are longer and allow for more tactics and movement on the battlefield compared to RTW.

In an attempt to set the record straight and show newcomers how powerful the cavalry charge can be, I created this short tutorial. I hope it reveals the mechanics of M2TW's cavalry charge and dispels the misconception that cavalry are bugged somehow. While the M2TW engine isn't perfect and sometimes cavalry charges are affected by pathfinding errors, once you understand the core mechanics (cavalry unit formation and distance to target), you will quickly appreciate how deadly charges can be.

[QuintusSertorius]

I have to say, the faster cavalry, with tighter formations and altered stats in the test-EDU charge much more successfully. I tended to find when I was struggling before, it was because I was charging from too close.

[Sint]

You know I I tried to make that point about a dozen times after EB2 was released.Some people still complained that it was not possible.

[Dago Red]

Fantastic work. I appreciate Marc Antony's advice too.

However, I for one am fully aware of M2TW's charge mechanics, and it still doesn't work well in EBII. People must be educated about 1-click charge orders and proper distancing yes. But, unit cohesion is a chronic problem here, frequently breaking a charge despite best efforts.

As said in the EDU thread, front rank charges and leaves the rest of the unit behind -- often so far behind the unit becomes scattered beyond recognition when the AI is in command (front rank perpetually chasing after a target while the 90% of the unit remains bugged somewhere else).

What EDU are you using?

[HaHawk]

But, unit cohesion is a chronic problem here, frequently breaking a charge despite best efforts.

As said in the EDU thread, front rank charges and leaves the rest of the unit behind -- often so far behind the unit becomes scattered beyond recognition when the AI is in command (front rank perpetually chasing after a target while the 90% of the unit remains bugged somewhere else).

Wow, you have a way with words. That's a very succinct explanation of one of the current issues in the mod. I actually have a funny outtake from the footage I recorded for the tutorial in which a SINGLE PEASANT charges about 300 meters away from his unit, for about 30 seconds, shouting the whole way lol (he must have thought everyone was right behind him ). It was bizarre and I never noticed it in Vanilla or in Stainless Steel. Upon comparing the two pathfinding text files, I noticed many large differences between the EBII values and those used in SS. But I do not know how to interpret the differences.

For reference:


EBII pathfinding (descr_pathfinding.txt):

        ; low load config
        load low
        {
            max_paths        80        ; maximum paths till shifting to the next loading
            total_nodes        480000        ; total nodes allocated across all paths
        }


        ; medium load config
        load medium
        {
            max_paths        40        ; maximum paths till shifting to the next loading
            total_nodes        240000        ; total nodes allocated across all paths
        }


        ; high load config
        load high
        {
            max_paths        20        ; maximum paths till shifting to the next loading
            total_nodes        120000        ; total nodes allocated across all paths
        }
        
        ; low priority config
        priority low
        {
            budget            0.10        ; percentage of budget for these paths
            max_nodes        2000        ; maximum nodes per path
            max_zone_nodes    500        ; maximum zone nodes per path
        }


        ; medium priority config
        priority medium
        {
            budget            0.25        ; percentage of budget for these paths
            max_nodes        4000        ; maximum nodes per path
            max_zone_nodes    1000        ; maximum zone nodes per path
        }
        
        ; high priority config
        priority high
        {
            budget            0.35        ; percentage of budget for these paths
            max_nodes        8000        ; maximum nodes per path
            max_zone_nodes    2000        ; maximum zone nodes per path
        }
        
        ; real time priority config
        priority real_time
        {
            budget            .35        ; percentage of budget for these paths
            max_nodes        8000        ; maximum nodes per path
            max_zone_nodes    2000        ; maximum zone nodes per path
        }
        
        ; quick test priority config
        priority quick_test
        {
            budget            .05        ; percentage of budget for these paths
            max_nodes        500        ; maximum nodes per path
            max_zone_nodes    100        ; maximum zone nodes per path
        }
    }

SS6.4 pathfinding (descr_pathfinding.txt):

        ; low load config
        load low
        {
            max_paths        10            ; maximum paths till shifting to the next loading
            total_nodes        2000        ; total nodes allocated across all paths
        }


        ; medium load config
        load medium
        {
            max_paths        20            ; maximum paths till shifting to the next loading
            total_nodes        4000        ; total nodes allocated across all paths
        }


        ; high load config
        load high
        {
            max_paths        300            ; maximum paths till shifting to the next loading
            total_nodes        8000        ; total nodes allocated across all paths
        }
        
        ; low priority config
        priority low
        {
            budget            0.20        ; percentage of budget for these paths
            max_nodes        10000        ; maximum nodes per path
            max_zone_nodes    2000        ; maximum zone nodes per path
        }


        ; medium priority config
        priority medium
        {
            budget            0.30        ; percentage of budget for these paths
            max_nodes        30000        ; maximum nodes per path
            max_zone_nodes    3000        ; maximum zone nodes per path
        }
        
        ; high priority config
        priority high
        {
            budget            0.50        ; percentage of budget for these paths
            max_nodes        40000        ; maximum nodes per path
            max_zone_nodes    4000        ; maximum zone nodes per path
        }
        
        ; real time priority config
        priority real_time
        {
            budget            1.0            ; percentage of budget for these paths
            max_nodes        50000        ; maximum nodes per path
            max_zone_nodes    5000        ; maximum zone nodes per path
        }
        
        ; quick test priority config
        priority quick_test
        {
            budget            1.0            ; percentage of budget for these paths
            max_nodes        300            ; maximum nodes per path
            max_zone_nodes    20            ; maximum zone nodes per path
        }
    }

The above are excerpted sections of descr_pathfinding.txt

I am especially suspicious of why "real time priority config" in SS is 1.0, but in EBII it is 0.35

[Roma_Victrix]

Marc Antony, what a cocky, alpha, meat-headed jock he was in that series. That's the sort of advice he'd given Octavian, alright.

Thanks for sharing the Youtube tutorial! It was a perfect illustration of how one should do the charge.

As for Dago Red's observation about the front ranks sometimes chasing after a unit while the rest are left elsewhere, if the enemy is doing that to you, take advantage of it if you can by dispersing (i.e. loose formation) a couple of your units and flanking it. They always easily rout when I do that.

[QuintusSertorius]

As said in the EDU thread, front rank charges and leaves the rest of the unit behind -- often so far behind the unit becomes scattered beyond recognition when the AI is in command (front rank perpetually chasing after a target while the 90% of the unit remains bugged somewhere else).

It may be due to charging distances (stat_charge_dist in the EDU), just investigating this at the moment.

As for Dago Red's observation about the front ranks sometimes chasing after a unit while the rest are left elsewhere, if the enemy is doing that to you, take advantage of it if you can by dispersing (i.e. loose formation) a couple of your units and flanking it. They always easily rout when I do that.

Taking advantage of a flaw isn't really good form. Besides which, it hampers your own units just as much.

[Roma_Victrix]

Taking advantage of a flaw isn't really good form. Besides which, it hampers your own units just as much.

Good form, Jack!

Who are you? Captain Hook or something? I kid, of course, but seriously, this is war, not a game of patty cakes. As the Roman general in RTW often says in the pre-battle speech: "It may not seem fair, but we are not here to be fair, only to win!"



Also, when in doubt, attack, as Marc Antony says.

In all seriousness, yes, it does become a pain sometimes, so if your EDU fixes that, I'll be glad to see it in my next campaign. Presently I'm way too far into my Koinon Hellenon campaign to stop it just for that.

[HaHawk]

It may be due to charging distances (stat_charge_dist in the EDU), just investigating this at the moment.

As far as I can tell, the reason for a "failed" or "aborted" charge is simply due to poor unit cohesion, not the charge distance. For example, a unit could be ordered to charge from halfway across the map — giving it ample time to get into formation and approach the enemy — and the charge might still fail.

Other times, the first few cavalry will strike, and then the rest suddenly abort and pull back. This happens when the unit gets too scattered (defined as the radius of the furthest unit from "unit center").

To illustrate with an extreme example, if one mounted cavalryman gets "stuck" (for example, it is surrounded by attackers while the rest of the unit retreats), it is often difficult for the rest of the main cavalry unit to carry out a charge until the trapped cavalryman dies or "returns to the flock". In other words, the charging unit must be complete and tightly grouped together (all units in one place, not scattered, caught on rocks, trees, etc.).

AFAIK, this is one of the changes that z3n is working on or perhaps already fixed... i.e., ensuring that units stay more close-knit and don't scatter so easily.

[QuintusSertorius]

As far as I can tell, the reason for a "failed" or "aborted" charge is simply due to poor unit cohesion, not the charge distance. For example, a unit could be ordered to charge from halfway across the map — giving it ample time to get into formation and approach the enemy — and the charge might still fail.

Other times, the first few cavalry will strike, and then the rest suddenly abort and pull back. This happens when the unit gets too scattered (defined as the radius of the furthest unit from "unit center").

To illustrate with an extreme example, if one mounted cavalryman gets "stuck" (for example, it is surrounded by attackers while the rest of the unit retreats), it is often difficult for the rest of the main cavalry unit to carry out a charge until the trapped cavalryman dies or "returns to the flock". In other words, the charging unit must be complete and tightly grouped together (all units in one place, not scattered, caught on rocks, trees, etc.).

AFAIK, this is one of the changes that z3n is working on or perhaps already fixed... i.e., ensuring that units stay more close-knit and don't scatter so easily.

I'm talking about infantry, here, who have a much bigger cohesion issue than cavalry. And charging distances have a big impact, alongside charging animation and charging pathfinding. z3n has fixed the last one, charging distances for cavalry are fine, but probably too short for infantry.

[HaHawk]

I'm talking about infantry, here, who have a much bigger cohesion issue than cavalry. And charging distances have a big impact, alongside charging animation and charging pathfinding. z3n has fixed the last one, charging distances for cavalry are fine, but probably too short for infantry.

Oh, I see! Yes, I've found that if only the first line of infantry charges, I have to wait until contact is made before telling the unit to attack again. This usually gets the rest of the unit to move their butts and help their poor comrades-in-arms in the front line

[QuintusSertorius]

z3n seems to know what's going on with pathfinding.

[z3n]

I believe SS has a mostly vanilla if not completely vanilla pathfinding file in that regard. Real_times_priority budget refers to the importance of the current pathfinding planning to the engine primarily and the CPU second. Nodes/paths are the amount of battlefield points utilized by the engine to make its calculations in battle. More of these may as I said before increase CPU load on very old CPU processors. More modern processors however will not suffer. Besides which the advantages of 3% more CPU use for increased priority/focus on pathfinding makes the ai (most importantly) imitate real humanlike movement without constantly moving about like a chicken with its head cut off.

Edit: as I feel a sudden need to energetically emphasize the importance of not having priority to high or your lower priority pathfinding eg routers/withdrawers/router chasers, flankers rear chargers will be affected.

Note that in mine I attempted to keep a balance, and btw, that is part of my older release of pathfinding values you have there for eb2, you should update



And this is oldest eb2

{    ; Configuration parameters for the scheduler
    scheduler_configuration
    {
        ; low load config
        load low
        {
            max_paths        10            ; maximum paths till shifting to the next loading
            total_nodes        2000        ; total nodes allocated across all paths
        }


        ; medium load config
        load medium
        {
            max_paths        20            ; maximum paths till shifting to the next loading
            total_nodes        4000        ; total nodes allocated across all paths
        }


        ; high load config
        load high
        {
            max_paths        300            ; maximum paths till shifting to the next loading
            total_nodes        8000        ; total nodes allocated across all paths
        }
        
        ; low priority config
        priority low
        {
            budget            0.20        ; percentage of budget for these paths
            max_nodes        10000        ; maximum nodes per path
            max_zone_nodes    2000        ; maximum zone nodes per path
        }


        ; medium priority config
        priority medium
        {
            budget            0.30        ; percentage of budget for these paths
            max_nodes        30000        ; maximum nodes per path
            max_zone_nodes    3000        ; maximum zone nodes per path
        }
        
        ; high priority config
        priority high
        {
            budget            0.50        ; percentage of budget for these paths
            max_nodes        40000        ; maximum nodes per path
            max_zone_nodes    4000        ; maximum zone nodes per path
        }
        
        ; real time priority config
        priority real_time
        {
            budget            1.0            ; percentage of budget for these paths
            max_nodes        50000        ; maximum nodes per path
            max_zone_nodes    5000        ; maximum zone nodes per path
        }
        
        ; quick test priority config
        priority quick_test
        {
            budget            1.0            ; percentage of budget for these paths
            max_nodes        300            ; maximum nodes per path
            max_zone_nodes    20            ; maximum zone nodes per path
        }
    }

[QuintusSertorius]

Alright, I seem to have mastered the one-click charge; it's definitely more effective than the EB1 style double-click charge. Question is, does the AI do it?

The updated pathfinding file definitely seems to make a difference, cavalry actually seem to chase down routers, now.

[HaHawk]

Alright, I seem to have mastered the one-click charge; it's definitely more effective than the EB1 style double-click charge. Question is, does the AI do it?

The updated pathfinding file definitely seems to make a difference, cavalry actually seem to chase down routers, now.

Wow, I can't wait to try the new pathfinding =) Is it save-game compatible?

Also, as for whether the AI does "single-click charges", yes, I can confirm that it does. It is especially clear with infantry. If you watch an attacking AI army (especially spear infantry that have javelins), you'll notice that the AI will not simply order units to run toward your line. Rather, each unit will march toward your position, halt, throw a javelin, reform, then charge in unison... Perhaps I'll post another video later

[QuintusSertorius]

Wow, I can't wait to try the new pathfinding =) Is it save-game compatible?

Also, as for whether the AI does "single-click charges", yes, I can confirm that it does. It is especially clear with infantry. If you watch an attacking AI army (especially spear infantry that have javelins), you'll notice that the AI will not simply order units to run toward your line. Rather, each unit will march toward your position, halt, throw a javelin, reform, then charge in unison... Perhaps I'll post another video later

I'll defer to z3n on the savegame compatibility; I'm not playing any campaigns at the moment, so I don't know.

Good news on the AI doing it, makes one-click charges feel a lot less like an exploit in favour of the human player.

[z3n]

Indeed, updated pathfinding helps the AI not only plan but execute it's plans

[z3n]

I started up a campaign sieged a city, then exited, replaced the pathfinding file with another version (though different) then loaded it back, fought the battle and all went well. Reinforcing that the file is loaded at the start of every battle. Additionally the eb2 cfg has clear file cache command which should help.

[k/t]

Where is the latest file?

[z3n]

Where is the latest file?

Check the updated pathfinding and bai thread