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### Re: Engines playing Musketeer Chess, good price

Posted: Mon Jan 13, 2020 11:01 pm
hgm wrote:
Mon Jan 13, 2020 1:58 pm
I think that what Daniel meant is that if b1 gets attacked, and your Cannon is at b0, you would not gain anything by playing Nc3 without gating the Cannon, (even if that was allowed, which I think it isn't), as this would surely make you lose the Cannon without compensation, as it could never be gated again. So gating at all times is automatic. This is why one can think of the Cannon as being already on c1 from the start, stacked under the Knight, both being captured at the same time when an enemy moves to b1. In the face of such a threat you can escape with the Knight, but the Cannon is a sitting duck until it is 'uncovered'.
Hi
This could be an interesting concept. In fact, it can be used to make engines ponder (research for optimal piece choice, optimal gating selection with each piece choice etc) converning various possible piece combinations etc.

As i said, this will be used for research (Neural Network) and not fir engine vs engine play. This research could result in an opening book for the first moves (for variety of game play in engine vs engine matches)

### Re: Engines playing Musketeer Chess, good price

Posted: Mon Jan 13, 2020 11:08 pm
musketeerchess wrote:
Mon Jan 13, 2020 10:22 pm
Daniel Shawul wrote:
Sun Jan 12, 2020 2:41 pm
@Ferdy Thanks, I now understand how the piece selection rules work

@HG My implementation was rather limited because I assumed that the fairy pieces are already in play. I did not even
implement how they get into play properly. It is my understanding that ranks 0 and 9 are "water" and can not be moved to
with other pieces. I have a holdings area just like that but is not file-restricted. So are there represented in the FEN as
e.g [C2D1c4d3] where they are preceded by file numbers? The drop rule is not a regular one and I probably need to implement a
special rule for it ( Not moved piece + drop-to-from square -- I like Ferdy representation with promotion letters but since I have a combo move
capability it may be easier for me to do "move b1c3 move C@b1" )
Edit: In a way the drops of pieces is square-restricted because it can only go to first/last rank. So the first time the target square becomes
empty, I drop it or lose it forever. In the latter case, do we just remove the piece from the holdings list forever?

@musketeerchess Thanks for the piece values. King's value is just a placeholder ( is actually infinity ). Anyway, I may decide to train
a neural network for it if it turns out to be simple enough.
Hi Daniel

The NN idea is great.
If the drop is lost the piece is removed and can no longer be dropped again. It’s possible to have it back when a pawn promotes. It can promote to any piece than begun the game. Even though the drop was lost it’s still possible to promote to this lodt piece as many times as there are promoted pawns

### Re: Engines playing Musketeer Chess, good price

Posted: Tue Jan 14, 2020 2:29 pm
Got a perft for cannon and leopard both already at b and g files.

Code: Select all

``*c****l*/rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR/*C****L* w KQkq - 0 1``

Code: Select all

``````Perft 4
0, 1
1, 20
2, 400
3, 8822
4, 193743``````

Code: Select all

``````Perft divide 4
h2h3 : 8381
h2h4 : 9245
a2a3 : 8381
a2a4 : 9245
e2e3 : 13015
e2e4 : 13041
g2g3 : 9261
g2g4 : 9244
b2b3 : 9261
b2b4 : 9248
d2d3 : 11853
d2d4 : 12325
f2f3 : 8381
f2f4 : 8849
c2c3 : 9188
c2c4 : 9656
b1a3c : 8364
b1c3c : 9226
g1f3l : 9219
g1h3l : 8360
LeafNodes : 193743``````

### Re: Engines playing Musketeer Chess, good price

Posted: Tue Jan 14, 2020 2:36 pm
Perft for cannon and leopard with castle and gate at rook file.

Code: Select all

``c******l/r1b1kb1r/1p3ppp/p1N2n2/1B1q4/8/1N1p4/PP1P1PPP/R1BQK2R/C******L w KQkq - 1 13``

Code: Select all

``````Perft 4
0, 1
1, 33
2, 1128
3, 35855
4, 1265960``````

Code: Select all

``````Perft divide 4
f2f3 : 39081
f2f4 : 44958
h2h3 : 45664
h2h4 : 47246
a2a3 : 45597
a2a4 : 45587
g2g3 : 44065
g2g4 : 39303
b3d4 : 59084
b3a5 : 51611
b3c5 : 52883
c6b4 : 8694
c6d4 : 8932
c6a5 : 7817
c6e5 : 9513
c6a7 : 7971
c6e7 : 8432
c6b8 : 8230
c6d8 : 8486
b5d3 : 75342
b5a4 : 39914
b5c4 : 55888
b5a6 : 61192
a1b1c : 47325
h1f1l : 41931
h1g1l : 43829
d1c2 : 52445
d1e2 : 8475
d1f3 : 52327
d1g4 : 58970
d1h5 : 55891
e1f1 : 46298
e1g1l : 42979
LeafNodes : 1265960``````

### Re: Engines playing Musketeer Chess, good price

Posted: Tue Jan 14, 2020 3:23 pm
It is not allowed to gate if the piece is pinned. Here white knight is pinned.

Code: Select all

``********/4k3/4b1m1/8/8/8/8/4M1P1/rN2K3/*H****** w - - 0 1``

Code: Select all

``````Perft 3
0, 1
1, 22
2, 564
3, 11873``````

Code: Select all

``````Perft divide 3
g2g3 : 465
g2g4 : 464
e2c1 : 604
e2g1 : 350
e2a2 : 455
e2b2 : 628
e2c2 : 680
e2d2 : 599
e2f2 : 630
e2c3 : 779
e2e3 : 545
e2g3 : 603
e2d4 : 754
e2e4 : 563
e2f4 : 729
e2e5 : 507
e2e6 : 502
e2e7 : 61
e1d1 : 522
e1f1 : 448
e1d2 : 501
e1f2 : 484
LeafNodes : 11873``````

### Re: Engines playing Musketeer Chess, good price

Posted: Tue Jan 14, 2020 4:41 pm
The WinBoard-AA package now contains a WinBoard version that no longer needs a gating suffix to the move in holdingless Seirawan. WinBoard already had code that made it resistant to missing promotion characters, supplying a default in that case (usually Q). So I just had to make the legality test recognizing first-rank moves with something behind it as a promotion. The promotion character was not as insignificant as I thought, so I now set it to the piece behind it, in a bit of a kludgy way. (It would not work with an odd number of ranks.) But for now that should do.

It will still add a gating suffix in the moves it sends to the engine.

### Re: Engines playing Musketeer Chess, good price

Posted: Tue Jan 14, 2020 4:58 pm
@Ferd
I get the first perft all correct.

The second one is wrong after and including perft(3)

The third one I miss it all. I thought you can gate whether the Knight becomes pinned or not.

Is there a complete list of all the rules of musketeer chess ? The official webpage I am sure
does not have this pinning rule.

### Re: Engines playing Musketeer Chess, good price

Posted: Tue Jan 14, 2020 5:42 pm
Daniel Shawul wrote:
Tue Jan 14, 2020 4:58 pm
@Ferd
I get the first perft all correct.
Ok good.
The second one is wrong after and including perft(3)
That position is complicated not sure if mine is even correct. If we don't agree at perft 3, here is the perft divide at 3. Can be of help to track down the issue.

Code: Select all

``````Perft divide 3

a2a3 : 1326
a2a4 : 1328
f2f3 : 1177
f2f4 : 1318
h2h3 : 1328
h2h4 : 1366
g2g3 : 1281
g2g4 : 1182
b3d4 : 1611
b3a5 : 1448
b3c5 : 1558
c6b4 : 245
c6d4 : 247
c6a5 : 221
c6e5 : 269
c6a7 : 223
c6e7 : 247
c6b8 : 229
c6d8 : 233
b5d3 : 1718
b5a4 : 1200
b5c4 : 1353
b5a6 : 1387
a1b1c : 1365
h1f1l : 1242
h1g1l : 1286
d1c2 : 1441
d1e2 : 283
d1f3 : 1575
d1g4 : 1787
d1h5 : 1659
e1f1 : 1383
e1g1l : 1339
LeafNodes : 35855``````
The third one I miss it all. I thought you can gate whether the Knight becomes pinned or not.

Is there a complete list of all the rules of musketeer chess ? The official webpage I am sure
does not have this pinning rule.
True, can't find it there too, I just remember that musketeer chess is like seirawan chess, and it does not allow such move. But there is actually a web page where you can play musketeer chess.
https://musketeerchess.net/games/musketeer/index.php

I tried it there and pinned piece even with gating capability (to make the gated piece as cover from attacking the king) is indeed cannot move.

### Re: Engines playing Musketeer Chess, good price

Posted: Tue Jan 14, 2020 6:39 pm
The third position is my fault -- I forgot about castling + musketeer drops combinations.

I will implement the pin rule to be like yours.

I must say this variant has so many specific rules I don't like, maybe because nebiyu does not have Sierawan variant.

thanks

### Re: Engines playing Musketeer Chess, good price

Posted: Tue Jan 14, 2020 8:14 pm
Ferdy wrote:
Tue Jan 14, 2020 5:42 pm
I tried it there and pinned piece even with gating capability (to make the gated piece as cover from attacking the king) is indeed cannot move.
This could of course be due to a bug in the Jocly implementation. It doesn't say anywhere that in case of doubt what Jocly does is decisive.

Surprisingly enough KingSlayer-Aramis also doesn't want to gate with a pinned piece. And WinBoard certainly considers it illegal.