Lozza - a Javascript web based UCI engine - update v1.10

[Sylwy]

Hello forum !

Impressive how good looks micro-Max 4.8w - of Maestro HGM - on aReNa GuI. Like a terribilist kid together with his sexy young mammy !

micro-Max is the - less polyglot - brother of Fairy-Max.

Well, after this very short match I think Lozza 1.10 is around 2000 Elo !

Regards,
S R

[Alex_Schmidt]

Hi,
Is there a possibility to run Lozza (with jsUCI or something similar) in Linux? I would like to use Lozza in Shredder GUI in Linux Mint/Ubuntu. Really like the engine, not too strong to lose every game without any chances, but strong enough to be a good opponent!
Thanks for your help.
Alex.

[op12no2]

Hi,
Is there a possibility to run Lozza (with jsUCI or something similar) in Linux? I would like to use Lozza in Shredder GUI in Linux Mint/Ubuntu. Really like the engine, not too strong to lose every game without any chances, but strong enough to be a good opponent!
Thanks for your help.
Alex.

Hi Alexander, thanks for trying Lozza.

I don't use Linux at all but the main jsUCI thread here:-

http://www.talkchess.com/forum/viewtopi ... ight=jsuci

Maybe somebody has compiled jsUCI for Linux; worth asking there perhaps.

The other possibility is to use node.js. Lozza would need a tweak to work with node.js, but I'd be happy to do it if you go down that route as I can test it on Windows (and done it before). Essentially install node.js then fire up Lozza with "node lozza.js", like jsUCI and ditto in the UIs.

The side effect of using node.js is that because the output from Lozza to the UIs is piped, the PVs don't display in real time; you get them all at once and once per move. It's a bit weird but does work. I've tried hard to force node into "TTY" mode but gave up in the end and removed the node stuff entirely. Easy to put it back though if you'd like to try it.

NB: Currently, Lozza (under jsUCI and node) cannot ponder nor accept any other signals while she's computing her move.

If you're on the go you can also play her on the web.

http://op12no2.me/toys/lozza/play.htm

If that is useful I'd again be happy to add a decent time control UI if you let me know what would be best for you.

[Alex_Schmidt]

Hi Colin,

I've asked Edmund if he has plans for a Linux version of jsUCI. Let's look what he's going to answer!
Concerning node.js I would be happy to test an enhancement of Lozza! It's a nice engine I like to play with. Since I don't use Lozza for analysis purposes the "side effects" you mentioned wouldn't be an issue for me.

Thanks, Alex.

[PK]

I've found two little bugs in this otherwise nice engine when I played it online. One problem is purely graphical: when I castle, only my king moves, and rook goes to the correct square only. The other is the lack of repetition draw claim, see below:

[pgn]
1. b2b3 e7e6 2. Bc1b2 Ng8f6 3. g2g3 d7d5 4. Bf1g2 Nb8c6 5. Ng1f3 Bf8b4 6. 0-0 0-0 7. d2d3 d5d4 8. a2a3 Bb4e7 9. c2c3 e6e5 10. c3d4 e5d4 11. Nb1d2 a7a5 12. Ra1c1 Rf8e8 13. Rc1c6 b7c6 14. Nf3d4 Bc8b7 15. Nd4c6 Qd8c8 16. Nc6e7 Re8e7 17. Bb2f6 g7f6 18. Nd2e4 Bb7e4 19. Bg2e4 Ra8b8 20. Qd1c2 Qc8e6 21. Rf1b1 f6f5 22. Be4f3 Qe6d6 23. Qc2c3 Qd6a3 24. Qc3f6 Qa3c5 25. Qf6g5 Kg8f8 26. Qg5h6 Kf8g8 27. Qh6g5 Kg8f8 28. Qg5h6 Kf8g8 29. Qh6g5 Kg8f8 30. Qg5h6 Kf8g8 31. Qh6g5 Kg8f8 32. Qg5h6 Kf8g8 33. Qh6g5 Kg8f8 34. Qg5h6 Kf8g8 35. Qh6g5 Kg8f8 36. Qg5h6 Kf8g8 37. Qh6g5 Kg8f8 38. Qg5h6 Kf8g8 39. Qh6g5 Kg8f8 40. Qg5h6 Kf8g8 {White to play on and hang the page}
[/pgn]

By the way, I have problems beating it when I play against it as if it was a blitz game

[op12no2]

I've found two little bugs in this otherwise nice engine when I played it online. One problem is purely graphical: when I castle, only my king moves, and rook goes to the correct square only. The other is the lack of repetition draw claim...

Hi Pawel,

Thanks for the feedback; can you clarify what you mean about the castling problem. I'm dragging the king and the castle follows OK. Dragging the castle is not implemented. I''ll add some tests for drawas etc - an oversight on my part.

By the way, I have problems beating it when I play against it as if it was a blitz game

It's getting there slowly - it's a lot of fun trying ideas out. Especially when after some fruitless ones you do a simple tweak and get this against the previous version:-


10=01=01=1=0=1=11=1=11=1101===1=1=1=1111==11111=11
01=10=10=0=1=0=00=0=00=0010===0=0=0=0000==00000=00

[op12no2]

Hi Pawel, I see what you mean about castling now - it moves the castle when the other side moves; I'll tweak something... thanks for the feedback.

[op12no2]

Latest version 1.12 is about 100 ELO better.

http://op12no2.me/toys/lozza

Source for use with jsUCI in Arena etc:-

http://op12no2.me/toys/lozza/lozza.js

By changing from PST for move ordering, to history + PST (if no history) I found I was able in increase LMR a bit more.

[Graham Banks]

Hi Colin,

can I download the engine itself for use in an external GUI in Windows?

Graham.

[op12no2]

Hi Colin,
can I download the engine itself for use in an external GUI in Windows?
Graham.

Hi Graham,

As a Javascript engine, that is in fact it - the source is interpreted in real time in web browsers or other applications that embed Javascript as a scripting language, like node.js.

To that end Edmund Moshammer embedded Google's amazing Javascript engine (called V8) in a C program called jsUCI which reads stdin and passes it to anything running in the V8 engine - and similarly passes anything from the engine back to stdout.

Thus effectively creating an entity that can be used with standard chess UIs. The Lozza source is a parameter to jsUCI, which fires it up in V8, which interprets it. Or to be more precise in the case of V8 actually compiles it in real time, runs it and optimises it in real time!

So to run Lozza in a std UI the sequence is: download jsUCI, download the Lozza source into the same folder, then fire it up with "jsuci lozza.js".

jsuci.exe - http://sourceforge.net/projects/jsuci/files/
lozza.js - http://op12no2.me/toys/lozza/lozza.js

This is a post on my blog on the same topic:-

http://op12no2.me/posts/1818

Note that jsuci exe will not be exactly that name depending on version.

From my personal perspective it would be lovely to see Javascript engines in rating lists but I would also fully understand if testers rejected them. It's an interesting decision...

My longer term plan is to write my own C program that overtly embeds Lozza, making the fact that it is Javascript opaque to the outside world. The engine would just an .exe in that form - but - exactly the same as the script that is being interpreted in web browsers.

Thanks for your interest...