Aart's Blog

Jim Ablett kindly ported Gary Linscott's engine GarboChess 3 to various platforms, including Android. I also made a dynamically linked binary available at the UCI engines for Android website . As can be seen in the screenshot below, the UCI engines does not provide many options, but it plays strong. Below the results of several quick matches on a Nexus S using random book opening play, one second-per-move, 32MB hash, and 8MB tablebases cache with the 3- and 4-piece Nalimov, Gaviota, Scorpio, Robbobases endgames on SD card. GarboChess3  - Stockfish 2.1         +0/-10/=0    0.00%  - Komodo32 2.03 AB      +0/-10/=0    0.00%  - IvanHoe-Beta v999947c +0/-10/=0    0.00%  - Pepito v1.59          +3/-4/=3    45.00%  - GarboChess3 JA        +2/-3/=5    45.00%  - GNU Chess 5.07.170.7b +7/-3/=0    70.00%  - Gaviota v0.83.0.3     +7/-3/=0    70.00%  - Rotor 0.6a            +6/-2/=2    70.00%  - RedQueen 0.9.8        +9/-1/=0    90.00%  - BikJump v2.1P         +9/-0/=1    95.00%

To test recently released versions of Android engines, I conducted a new tournament between the top UCI engines on a Nexus One using a random book opening play, one second-per-move, 32MB hash, and 8MB tablebases cache with the 3- and 4-piece Robbobases endgames on SD card. Congrats again to the Stockfish team!                        1         2         3         4         5 1 Stockfish 2.1            *     54.0-46.0 60.5-39.5 64.5-35.5 65.5-34.5 244.5/400 2 Komodo32 2.03 AB     46.0-54.0     *     46.5-53.5 52.5-47.5 66.0-34.0 211.0/400 3 Critter 1.2 32-bit   39.5-60.5 53.5-46.5     *     51.5-48.5 58.0-42.0 202.5/400 4 RobboLito 0.085e4l   35.5-64.5 47.5-52.5 48.5-51.5     *     62.0-38.0 193.5/400 5 IvanHoe-Beta 999947c 34.5-65.5 34.0-66.0 42.0-58.0 38.0-62.0     *     148.5/400

Richard Vida released Critter 1.2 for various platforms, including ARM-based Android devices. Below you can see some screenshots of this UCI engine running in Chess for Android . To get a rough idea of the strength of this new engine, I conducted a few quick matches with other engines on a Nexus One using a random book opening play, one second-per-move, 32MB hash, and 8MB tablebases cache with the 3- and 4-piece Nalimov, Gaviota, Scorpio, Robbobases endgames on SD card. More games upcoming. Critter 1.2  - RobboLito 0.085e4l     3.5 - 6.5  +2/-5/=3   35.00%  - Komodo32 2.03 AB       5.0 - 5.0  +4/-4/=2   50.00%  - Stockfish 2.1          6.0 - 4.0  +4/-2/=4   60.00%  - GNU Chess 5.07.170.7b  7.0 - 3.0  +7/-3/=0   70.00%  - Gaviota v0.83          8.0 - 2.0  +7/-1/=2   80.00%  - Rotor 0.6a             9.5 - 0.5  +9/-0/=1   95.00%  - Toga II 1.4.1SE        9.5 - 0.5  +9/-0/=1   95.00%  - RedQueen 0.9.8        10.0 - 0.0 +10/-0/=0  100.00%  - BikJump v2.1P         10.0 - 0.0 +10/-0/

The new Komodo has been heavily tested by many chess fans, and Larry and Don had to make a few bug fixes. You can find an Android binary of the latest version 2.03 at the usual place . Quick tournament on a Nexus S: 1   Komodo32 2.03 AB  +34/-23/=43 55.50%   55.5/100 2   Komodo32 2.01 AB  +23/-34/=43 44.50%   44.5/100

Another tournament between the top engines on a Nexus One, 32MB hash, one-second per move.                      1           2           3                                    1 Stockfish 2.0      ***         48.5 - 51.5 59.0 - 41.0 107.5/200 2 RobboLito 0.085e4l 51.5 - 48.5 **          50.0 - 50.0 101.5/200 3 Komodo32 2.01 AB   41.0 - 59.0 50.0 - 50.0 **           91.0/200

Don Dailey and Larry Kaufman released version 2 of their chess engine Komodo. You can find an ARM-based Android binary on UCI engines for Android . The new release seems stronger than the already impressive previous version. A quick one second-per-move, 32MB hash tournament on a Nexus S against Komodo1.3 resulted in 73 vs. 27 in favor of Komodo2. 1   Komodo32 2AB     +58/-12/=30 73.00%   73.0/100 2   Komodo32 1.3 JA  +12/-58/=30 27.00%   27.0/100 The new Komodo scored 48.5% against Stockfish 2.1 under the same settings. 1   Stockfish 2.1  +38/-35/=27 51.50%   51.5/100 2   Komodo32 2AB   +35/-38/=27 48.50%   48.5/100

After this previous tournament , I conducted a tournament between various versions of the top engines under the same settings with more games. The results are shown below. Congrats to the stockfish team for winning this tournament!                            1 Stockfish 2.0           323.5/500 2 Stockfish 2.1           316.5/500 3 RobboLito 0.085e4l      250.5/500 4 RobboLito 0.085g3l      240.0/500 5 IvanHoe-Beta v999947c   196.5/500 6 Komodo32 1.3 JA         173.0/500

I computed the perft number for 8x8 checkers for depth 24 with the same distributed implementation I used earlier for depths up to 23. Below you see the perft breakdown per move (called "divide") from the initial position for depths 22, 23, and 24. move         divide(22)       divide(23)        divide(24) ---------------------------------------------------------- 12-16:  243598269855110 1123463594881857  5192042148594780 11-16:  246743868125768 1131373985922218  5248615918291379 11-15:  209016678583301  984253557821317  4602138522979438 10-15:  215412869777867 1000606302770349  4643700995955222 10-14:  184865466345796  856779998157523  3988937724259353  9-14:  213736468971938 1003310451936358  4712325943133747  9-13:  288999100078322 1337748969176591  6263620622082081 ----------------------------------------------------------        1602372721738102 7437536860666213 34651381875296000

I just released version 2.9 of Chess for Android, available from the Android market or as direct download . New features include: + built-in engine improvements (thanks to Attila for reporting) + various UCI improvements        engine tournament feature (with resume option)        option settings saved per engine        more flexible uninstall or clear options window        added robbobases support

I conducted a full tournament between 17 currently available UCI engines for Android as well as the simple built-in Java engine. The tournament consisted of pair-wise matches between all engines for 10 games with random book opening play, one second-per-move, 32MB hash, and 8MB tablebases cache with the 3- and 4-piece Nalimov, Gaviota, Scorpio, Robbobases endgames on SD card. The 1530 games lasted about two days running full time on a Nexus One phone (without a single crash!). The results are shown below. 1  Stockfish 2.0                   157.5/170 2  RobboLito 0.085g3l              152.5/170 3  IvanHoe-Beta version 999947c    145.0/170 4  Komodo32 1.3 JA                 137.0/170 5  Toga II 1.4.1SE                 130.5/170 6  Pepito v1.59                    104.0/170 7  Daydreamer 1.75 JA              100.5/170 8  Rotor 0.6a                       98.0/170 9  gaviota v0.80.0.107              87.5/170 4647.75 10 GNU Chess 5.07.170.7b            87.5/170 4455.25 11 RedQuee