Chess engine: Eubos 2.4

Eubos - a basic Java chess engine, written for kicks. Uses jcpi for the UCI protocol parts. Kind of weak, doesn't evaluate for king safety, for example. Now uses transpostion hashing, but because it runs in the Java VM on a bog standard PC, doesn't search very deeply (around 100K Nodes/s, though this is actually quite hard to evaluate due to the hashing). 

Author: Chris Bolt Rating CEDR=2385

v.2.4

Simplified the negamax search function and removed some specific code from older Eubos versions which was making the search inefficient.

Refactored the isAttacked() and Piece mobility calculation functions to use dumb7Fill algorithm. This has also increased the efficiency of Eubos.

Reworked Transposition table to cull least used 20% of Transpositions only after best move calculation is completed.

The evaluation function is unaltered since Eubos v2.2.

To install Eubos as an engine in Arena:
1. Select Engines > Install New Engine
2. In the file browser dialog that appears, change the drop down to *.bat
3. Navigate to the Eubos binary location, select the Eubos.bat
4. Select UCI protocol to communicate with Eubos
5. That's it! 

Eubos 2.4 download