Go Board SVG Generator

A simple Python script that generates printable Go board diagrams (9×9, 13×13, 19×19) as SVG files.
It uses only Python’s standard library, so it runs on Linux, macOS, and Windows without extra dependencies.

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Features

• Generates Go boards with correct grid and star points (hoshi).
• Supports 9×9, 13×13, and 19×19 board sizes.
• Fully configurable via config.json:
  • grid_size: board size (9, 13, or 19).
    Note: if SGF overlay is enabled, this is overridden by the SZ[...] in the SGF file.
  • line_thickness: grid line stroke width (can be fractional, even < 1).
  • star_diameter: size of the star points (hoshi).
  • grid_color: color of the lines and hoshi (any valid CSS color).
  • background_color: default board background color (any valid CSS color).
• White background by default, but you can also make wood-tone boards by using:
  • background_color: "#f1d18a"
• SGF overlay support:
  • Load any .sgf file to render game positions or problems on top of the board.
  • Works with SGF files exported from Online-Go.com and other servers/clients that follow the SGF standard.
  • Initial stones (AB, AW, AE) and sequential moves (B[...], W[...]) are supported.
  • Board size from the SGF (SZ[...]) automatically overrides the grid_size in config.
• Flexible rendering options (in config.json → sgf.render):
  • mode:
    • "position" → apply all moves, show the final position.
    • "moves" → apply the first N moves (controlled by moves_limit).
  • moves_limit: limit number of moves applied (0 = all).
  • numbering:
    • "none" → no numbers.
    • "moves" → number only the played moves.
    • "all" → number setup stones and moves in order.
  • Stone drawing and labels are customizable:
    • stone_radius_scale → stone size relative to grid spacing.
    • move_number_font_scale → font size for numbers relative to grid spacing.
    • number_color → text color for move numbers.
    • outline_color → stroke around stones to improve visibility.
• Export control:
  • Choose which SVGs to generate in config.json → export.variants:
    • "board" → grid + hoshi only.
    • "stones" → stones (and optional numbers) only.
    • "both" → full board (grid + hoshi + stones).
  • Independent background control for each variant:
    • "transparent" → no background fill.
    • "use_config_background" → uses the top-level background_color.
    • Or any CSS color string (e.g., "black", "#000000", "beige").
  • Example: transparent board + transparent stones + board+stones with background.

Because the output is SVG, you can scale and print at any size without losing quality.

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Requirements

• Python 3.7+ (tested with 3.7–3.12).
• No external libraries required.

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Usage

1. Place the script, your config.json, and any .sgf files in the same directory.

2. Example config.json without SGF (empty board):

   {
     "grid_size": 19,
     "line_thickness": 0.8,
     "star_diameter": 2.5,
     "grid_color": "black",
     "background_color": "white",
     "sgf": {
       "enabled": false
     },
     "export": {
       "variants": ["board", "stones", "both"],
       "board_background": "use_config_background",
       "stones_background": "transparent",
       "both_background": "use_config_background",
       "name_suffix": ""
     }
   }

3. Example config.json with SGF overlay:

   {
     "grid_size": 19,
     "line_thickness": 0.8,
     "star_diameter": 2.5,
     "grid_color": "black",
     "background_color": "white",
   
     "sgf": {
       "enabled": true,
       "path": "example_9x9.sgf",
       "render": {
         "mode": "moves",
         "moves_limit": 0,
         "numbering": "moves",
         "number_color": "#ffffff",
         "outline_color": "#000000",
         "stone_radius_scale": 0.42,
         "move_number_font_scale": 0.44
       }
     },
   
     "export": {
       "variants": ["board", "stones", "both"],
       "board_background": "transparent",
       "stones_background": "transparent",
       "both_background": "use_config_background",
       "name_suffix": ""
     }
   }

4. Run the script:

   # Linux / macOS
   chmod +x go_board.py
   ./go_board.py
   
   # Windows
   python go_board.py

5. The script creates files like:

   go_9x9_board.svg
   go_9x9_stones.svg
   go_9x9_both.svg
   

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Notes

• If SGF overlay is enabled, grid_size is ignored — the board size from the SGF takes priority.
• For multiple games, keep .sgf files alongside the script and update config.json to point at the one you want.
• Output path: the SVG files are written to the current working directory.
• Works with SGF files exported from Online-Go.com and most SGF-compatible clients.
• The default line spacing and margins (in mm) are set inside the script.
  You can change them if you need precise physical dimensions for printing.

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License

This project is free to use and modify.