Add HEN Support for position import, export, and teaching games

[hemme]

Hi @sanderland

I am the author of HEN, a new serialization format specifically designed to represent static positions in Go (similar to how FEN works for Chess).

I believe this format would be a valuable addition to KaTrain and I would like to suggest the following features:

• Paste HEN from Clipboard. This should be straightforward to implement: when the user pastes content, if it is a valid HEN string, KaTrain could convert it to SGF and load it onto the goban just as it would with an SGF file.
• Import position from PNG+hen. Allow the Load Game command to browse for PNG images. Import a goban position if the selected PNG has HEN metadata.
• Copy as HEN. Add a command that copies the current goban position to the clipboard in HEN format.
• New Teaching Game from HEN. Allow users to start a new teaching game against a bot from a position specified by a HEN string.

I would also be happy to help with the implementation. For example, I can provide and maintain SGF-to-HEN and HEN-to-SGF conversion functions in various programming languages ‹through a dedicated repository / e.g. hen-python,
making integration easier for KaTrain and other Go-related projects (just let me know!)

I think these features would make it easier to share, analyze, and discuss Go positions across different tools and platforms.

[sanderland]

Unlikely to support this unless it turns out to be popular. Given the widespread adoption of SGF, which isn't particularly long or cumbersome, it doesnt seem very necessary

[PJTraill]

This format was announced by OP at https://www.reddit.com/r/baduk/comments/1t9ijbs/hen_a_new_textbased_format_designed_to_write/ and discussed there, but I do not think it seemed to fill much of a need.

[hemme]

Unlikely to support this unless it turns out to be popular. Given the widespread adoption of SGF, which isn't particularly long or cumbersome, it doesnt seem very necessary

I wasn't expecting this answer, which puts the whole issue in a sort of Catch-22, since the popularity of a new format like HEN depends on its adoption by the most popular platforms.

[hemme]

This format was announced by OP at https://www.reddit.com/r/baduk/comments/1t9ijbs/hen_a_new_textbased_format_designed_to_write/ and discussed there, but I do not think it seemed to fill much of a need.

Also see the discussion about HEN adoption here: https://www.reddit.com/r/baduk/comments/1tma9x3/imagine_if_we_could_share_kifu_diagrams_tsumego/

[sanderland]

I found the SGF examples on your github page to be more readable and similarly verbose to your format, so to each their own I guess. Nothing wrong with creating a new format for your own needs of course, but SGF is pretty ubiquitous and I'm not sure you've articulated a convincing reason for creating a new standard.

I think this comment on reddit captures my sentiment. Along with the general feeling that a new standard needs a much stronger motivation than shaving off a few characters.

[hemme]

This FR is related to the following vision:

«Imagine if we could share [kifu diagrams | tsumego | joseki] images (PNG+hen) and study them directly in our favorite app.» - Of course, this could also apply to PNG+SGF files (why not?).

To achieve this, I suppose one should proceed step by step: first, by integrating HEN as such (as in this FR), and then by allowing PNG import and export (which could be a separate FR).

[sanderland]

I don't see that as an improvement over e.g. http://eidogo.com/#A8cDEJs2

[hemme]

For example, one could directly share an image (this one has HEN tEXt metadata) that can be opened by a Go software!

E.g.:

(in this example, I build the PNG from my worker
https://wrk.GoShawk.cc/cx/hen_18Fwb_17Cw3b_16Cb2wb_15Ebw.F15w.b.png (as you can see, HEN can be used in a URL with no escapes / encoding)

[hemme]

My fork currently implements the following new menu item, which open a new dialog to import .hen files or PGN+hen files:

The menu:

The dialog (fragment):

Paste from clipboard supports HEN strings too.

Everything is working thanks to hen-python library

Features are localized in all supported languages (thanks to LLM).

[hemme]

For example: here's KaTrain analyzing the position related to this post, after importing the PGN+hen file