ProDeo 2.6

The do it yourself version

 

The goal of this version is to make the last engine (version 2.2) more flexible than it already was up to a point that you almost can call yourself a chess programmer.

 

The basic tool for that is the Personality Creator for ProDeo 2.6 coming with descriptions and help pages. Apart from that you can also create (modify) most of the evaluation tables with a standard text editor giving you almost complete control over the engine, more below.

 

Sub-goals of this release are 1) playing style improvement and 2) increase of playing strength. On both issues hints will be given and following (2) you can outperform the author on playing strength quite easily.

Playing Strength Improvements

Category

Item(s)

old

change

Games

Score

LOS

Late Move Reductions

Reduce less

off

on

9.000

51.2%

99.8%

Late Move Reductions

Use Log Formula

off

on

9.000

51.4%

99.9%

King Safety paramters

King Safety

King Front Pawn Square

105

8

125

0

16.000

50.9%

99.8%

 

 

 

 

 

 

 

Playing style suggestions

Category

Item(s)

old

change

Description

King Safety paramters

King Front Square

King Front Pawn Square

8

8

16

0

Much sharper in King Attacks with a neglictable elo loss of 2 points based on 16.000 games.

 

 

 

 

 

 

 

 

 

 

During development time the above 2 tables may (or may not) be updated, so stay tuned about the progress.

 

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Tuning King Safety

The new parameters in the Personality Creator need some explanation, consider the diagram.

 

The surrounding squares of kings are evaluated and depending on the place of the king on the board for the white king that means 7 squares and for the black king 11 squares. Each square has its own evaluation weight represented by 4 charachters, see table below.

 

The O squares are the most important squares with the most evaluation characteristics and highest weights.

 

The PGN file I used for testing the new King Safety fine tune options.

Squares

Paramters in use

Weight

Description [ situation BKg7 ]

Action

O

King Front Square

King Undefended Square

King Front Pawn Square

King Queen Check Front

King Shelter Front Square

8

8

8

32

8

when under attack by white piece

when under attack by white piece and undefended

when no black piece

when safe white queen check possible

when black pawn

weight +8

weight +8

weight +8

weight +32

weight - 8

 

 

 

 

 

+

King Flank Square

King Undefended Square

King Queen Check Flank

King Shelter Flank Square

8

8

16

8

when under attack by white piece

when under attack by white piece and undefended

when safe white queen check possible

when black pawn

weight +8

weight +8

weight +16

weight - 8

 

 

 

 

 

X

King Behind Square

King Undefended Square

King Queen Check Flank

8

8

16

when under attack by white piece

when under attack by white piece and undefended

when safe white queen check possible

weight +8

weight +8

weight +16

 

 

 

 

 

 

King Pawn Attack

8

when black pawn is under attack by white piece

weight +8

 

 

 

 

 

ALL

King Safety Modus

 

Calculation of the total material involved attacking the black king and increase weight depending on the modus [ moderate | normal | aggressive].

 

Moderate - weight +0|+8

Normal - weight +0|+8|+16|+24

Aggressive - weight +0|+8|+16|+24|+32|+40|+48|+56

 

The calculated weight serves as an index to an evaluation table (see King Safety below) to make up the final score of the attack on the black king multiplied with the factor 1.05 of the [King Safety = 105] parameter. Values vary from 0.00 up to 6.00 as absolute maximum using the default 105 value.

 

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Tuning the Piece Square Tables

Click to enlarge

 

Open the file PST.TXT with a text editor and modify the cells according your wishes.

 

Rules

 

1. Negative values are not allowed;

2. Values must be 2 characters;

3. Don't change the format.

 

Not followig these rules will result in ignoring the changes.

 

_______________________________________________________________________________________________

 

Tuning PST Pawn evaluation

Notes

 

1. The tables for the black pieces are automatically mirrored by the program.

 

2. Modifying the PST's for the endgame is not (yet) supported.

Click to enlarge

 

Open the file PAWNS.TXT with a text editor and modify the cells according your wishes.

 

The same rules applies as for the above Piece Square Tables.

 

____________________________________________________________________________________________________

 

Tuning other evaluation tables

a couple of important

ones only

 

Open the file TABLES.TXT with a text editor and modify the cells according your wishes.

 

  1. Modify the cells of the PST Knight Outpost Bonus as you are used to in the meantime.

 

  1. Modify the King Safey table with decimal values.

 

 

 

 

 

 

 

 

 

 

 

 

 

As explained above the calculated total weight serves as an index to this table and becomes the final score for the king we are evaluating.

 

  1. Modify the Double Attack Bonus table with decimal values.

 

 

 

 

 

 

 

Apply a bonus when two pieces are hanging, the lowest hanging piece usually is lost and serves as an index to the above table. For example, when the white Queen attacks a Rook and a Pawn at the same time the index =1 and thus a bonus of 0.25 is given, or, if a white pawn on E5 attacks both the black knight on F6 and the black bishop on D6 the index becomes 2 if the losing square is defended and 3 if the losing square is undefended. Depending on that a bonus of 0.50 or 0.75 is given.

 

  1. Modify the Bishop Pair Bonus table with decimal values.

 

 

 

 

 

 

 

Evaluation of the Bishop Pair depends on the number of own pawns on the board, usually meaning the Bishop Pair becomes more worth in the end game.

 

  1. Modify the Immobile Knight penalty table with normal 2 character numbers.

 

 

 

 

 

 

 

Knights that have few squares to go (are immobile) are penalized.

 

  1. Modify the Immobile Bishop penalty table with normal 2 character numbers.

 

 

 

 

 

 

Bishops that have few squares to go (are immobile) are penalized.

 

  1. Modify the Pins and Xray threats tables.

 

 

 

 

 

 

 

Examples:

A white bishop on G5 that pins a black knight on F6 because of a black queen on D8 or E7 gets a bonus of 15.

A white rook on E1 that pins a black bishop on E6 because of a BK or BQ on E7 or E6 gets a bonus of 40.

A white queen on F3 that pins a black rook on C6 because of a black king on A8 or B7 gets a bonus of 40.

 

Likewise for Xray threats:

 

 

 

 

 

 

 

Examples:

- WBg2 + WNf3 vs a BK|BQ|BR on d5 contains a hidden threat and gets a 20|15|20 bonus accordingly.

- WRe1 + WBe3 vs a BK|BQ on e4|e5|e6|e7|e8 contains a hidden threat and gets a bonus of 40.

- WQf3 + WNd5 vs a BK on c6|b7|a8 contains a hidden threat and gets a bonus of 40.

 

  1. Modify the Piece Value tables with decimal values.

 

 

 

 

 

 

 

 

 

 

 

 

 

The most important table of a chess engine, the value of the pieces. Changes are extremely sensitive.

 

____________________________________________________________________________________________________

 

 

Seems to be enough (and perhaps already too much) for one version. Good luck with all the new possibilities

King Safety
+----+----+----+----+----+----+----+----+----+----+----+----+----+----+----+----+
|  0 |  1 |  2 |  3 |  4 |  5 |  6 |  7 |  8 |  9 | 10 | 11 | 12 | 13 | 14 | 15 |
|----+----+----+----+----+----+----+----+----+----+----+----+----+----+----+----+
|0.00|0.02|0.03|0.06|0.12|0.18|0.25|0.37|0.50|0.75|1.00|1.25|1.50|1.75|2.00|2.25|
+----+----+----+----+----+----+----+----+----+----+----+----+----+----+----+----+

+---+----+----+----+----+----+----+-----+----+----+----+----+----+----+----+
| 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 |
+----+----+----+----+----+----+----+----+----+----+----+----+----+----+----|
|2.50|2.75|3.00|3.25|3.50|3.75|4.00|4.25|4.50|4.75|5.00|5.25|5.50|5.75|6.00|
+----+----+----+----+----+----+----+----+----+----+----+----+----+----+----+
Double Attack Bonus
+----+----+----+----+----+----+----+----+----+----+----+
|  0 |  1 |  2 |  3 |  4 |  5 |  6 |  7 |  8 |  9 | 10 |
|----+----+----+----+----+----+----+----+----+----+----| 
|0.00|0.25|0.50|0.75|1.00|1.00|1.00|1.00|1.00|1.00|1.00|
+----+----+----+----+----+----+----+----+----+----+----+
Bishop Pair depending on the number of the pawns
+----+----+----+----+----+----+----+----+----+
|  0 |  1 |  2 |  3 |  4 |  5 |  6 |  7 |  8 |
|----+----+----+----+----+----+----+----+----+
|0.50|0.50|0.50|0.50|0.37|0.25|0.12|0.06|0.03|
+----+----+----+----+----+----+----+----+----+
Immobile Knights penalty based on too few squares to move
+----+----+----+----+----+----+----+----+----+----+----+----+
| 0  |  1 |  2 |  3 |  4 |  5 |  6 |  7 |  8 |  9 | 10 | 11 |
|----+----+----+----+----+----+----+----+----+----+----+----+
| 64 | 25 | 12 | 00 | 00 | 00 | 00 | 00 | 00 | 00 | 00 | 00 |
+----+----+---+-----+----+----+----+----+----+----+----+----+
Immobile Bishop penalty based on too few squares to move
+----+----+----+----+----+----+----+----+----+----+----+----+----+----+----+
| 0  |  1 |  2 |  3 |  4 |  5 |  6 |  7 |  8 |  9 | 10 | 11 | 12 | 13 | 14 |
|----+----+----+----+----+----+----+----+----+----+----+----+----+----+----+
| 60 | 60 | 50 | 40 | 30 | 20 | 10 | 00 | 00 | 00 | 00 | 00 | 00 | 00 | 00 |
+----+----+----+----+----+----+----+----+----+----+----+----+----+----+----+
White Bishop Pins  White Rook Pins  White Queen Pins
+----+----+----+   +----+----+      +----+
| BR | BQ | BK |   | BQ | BK |      | BK |
|----+----+----+   +----+----+      +----+
| 20 | 15 | 20 |   | 40 | 40 |      | 40 |
+----+----+----+   +----+----+      +----+
White Bishop Xray threat   White Rook Xray threat   White Queen Xray threat
+----+----+----+           +----+----+              +----+
| BR | BQ | BK |           | BQ | BK |              | BK |
|----+----+----+           +----+----+              +----+
| 20 | 15 | 20 |           | 40 | 40 |              | 40 |
+----+----+----+           +----+----+              +----+
Piece Values Middle Game
+----+----+----+----+----+----+----+----+----+----+----+----+
| Wp | Wn | Wb | Wr | Wq | Wk | Bp | Bn | Bb | Br | Bq | Bk |
|----+----+----+----+----+----+----+----+----+----+----+----+
|0.75|2.92|3.04|4.62|8.88| 0  |0.75|2.92|3.04|4.62|8.88|  0 |
+----+----+----+----+----+----+----+----+----+----+----+----+

Piece Values Endgame Game
+----+----+----+----+----+----+----+----+----+----+----+----+
| Wp | Wn | Wb | Wr | Wq | Wk | Bp | Bn | Bb | Br | Bq | Bk |
|----+----+----+----+----+----+----+----+----+----+----+----+
|0.75|2.54|2.62|4.37|8.71|  0 |0.75|2.54|2.62|4.37|8.71|  0 |
+----+----+----+----+----+----+----+----+----+----+----+----+

Approx 5.3 Mb

Remark

I will play a few more 16.000 games matches with changes that have potential and report on the top of the page but thereafter you are at your own creativity. Questions are always welcome of course.