# FS51

A compatibility layer that makes formspec_version 3 (and later) formspecs
render more correctly in Minetest 5.1.0 and earlier.

This will work with most mods without any additional configuration. If you want
to disable automatic formspec translation, add
`fs51.disable_monkey_patching = true` to minetest.conf.

## Why?

Minetest 5.1.0 introduced changes to formspecs that made them much less painful
to create and work with. However, formspecs are interpreted client-side and to
take advantage of these changes you would normally need to force everyone to
upgrade Minetest. This mod detects these older clients and modifies formspecs
sent to them to try and make sure they are at least usable.

## How to use

1. Install the mod
2. Hope it works properly and doesn't break anything

## Troubleshooting

 - If your mod stores `minetest.show_formspec` during load time, you'll need to
   add `fs51` as an optional dependency to `mod.conf` so it can use the patched
   show_formspec code.
 - If a mod you use has broken node formspecs with fs51 enabled, try adding
   `fs51.disable_meta_override = true` to minetest.conf (and please open an
   issue against fs51).

## Dependencies

This mod depends on my [formspec_ast] library.

## API functions

You probably don't need to use these unless you're embedding fs51 outside of
Minetest or are using node formspecs.

 - `fs51.backport(tree)`: Applies backports to a [formspec_ast] tree and
    returns the modified tree. This does not modify the existing tree in place.
 - `fs51.backport_string(formspec)`: Similar to
    `formspec_ast.unparse(fs51.backport(formspec_ast.parse(formspec)))`.

*Unlike the automatic backporting, these functions will preserve newer elements
such as hypertext and background9 so the formspec will still work properly with
newer clients.*

 [formspec_ast]: https://content.minetest.net/packages/luk3yx/formspec_ast