Subject: [bug#50273] [PATCH] gnu: Add python-pyxel.

From: Maxim Cournoyer <[email-masked]>
Date: Mon, 30 Aug 2021 14:40:23 -0400

Hello Leo,

Leo Prikler <[email-masked]> writes:

> * gnu/packages/game-development.scm (python-pyxel): New variable.
> ---
>  gnu/packages/game-development.scm | 55 +++++++++++++++++++++++++++++++
>  1 file changed, 55 insertions(+)
>
> diff --git a/gnu/packages/game-development.scm b/gnu/packages/game-development.scm
> index 2a58848dce..3e21d411cf 100644
> --- a/gnu/packages/game-development.scm
> +++ b/gnu/packages/game-development.scm
> @@ -1484,6 +1484,61 @@ visual novels, while its Python scripting is enough for complex simulation
>  games.")
>      (license license:expat)))
>  
> +(define-public python-pyxel
> +  (package
> +    (name "python-pyxel")
> +    (version "1.4.3")
> +    (source
> +     (origin
> +       (method git-fetch)
> +       (uri
> +        (git-reference
> +         (url "https://github.com/kitao/pyxel")
> +         (commit (string-append "v" version))))
> +       (file-name (git-file-name name version))
> +       (sha256
> +        (base32
> +         "0bwsgb5yq5s479cnf046v379zsn5ybp5195kbfvzr9l11qbaicm9"))
> +       (modules '((guix build utils)))
> +       (snippet
> +        '(begin
> +           (delete-file-recursively "pyxel/core/bin")))))
> +    (build-system python-build-system)
> +    (arguments
> +     `(#:tests? #f ; "Tests" are actually example programs that never halt.
> +       #:phases
> +       (modify-phases %standard-phases
> +         (add-after 'unpack 'patch-build-files
> +           (lambda* (#:key inputs #:allow-other-keys)
> +             (substitute* "setup.py"
> +               (("\"pyxel\\.core\\.bin\\.(.*)\"," all arch)
> +                (if (string=? arch "linux")
> +                    all
> +                    "")))
> +             (let* ((sdl2 (assoc-ref inputs "sdl2")))
> +               (substitute* "pyxel/core/Makefile"
> +                 (("`sdl2-config --cflags`")
> +                  (string-append "-I" sdl2 "/include/SDL2 -D_REENTRANT"))
> +                 (("`sdl2-config --libs`")
> +                  (string-append "-L" sdl2 "/lib "
> +                                 "-Wl,-rpath," sdl2 "/lib "
> +                                 "-Wl,--enable-new-dtags -lSDL2"))))))

The above could benefit from some extra commenting to explain the choice
of linker options (--enable-new-dtags ?) or C preprocessor variables
(-D_REENTRANT).  I'd have to dig a bit deeper than I'd like to have an
understanding of these.

> +         (add-before 'build 'prebuild
> +           (lambda _
> +             (invoke "make" "-C" "pyxel/core"))))))
> +    (inputs
> +     `(("gifsicle" ,gifsicle)
> +       ("sdl2" ,(sdl-union (list sdl2 sdl2-image)))))
> +    (native-inputs
> +     `(("gcc" ,gcc-10)))                  ; for std::filesystem
> +    (home-page "https://github.com/kitao/pyxel")
> +    (synopsis "Retro game engine for Python")
> +    (description "Pyxel is a game engine inspired by retro gaming consoles.
> +It has a fixed 16-color palette, can hold up to 3 image banks and 8 tilemaps
> +(256x256 pixels each) and 4 sound channels with 64 definable sounds.  It
> +also comes with a built-in image and sound editor.")
> +    (license license:expat)))
> +
>  (define-public grafx2
>    (package
>      (name "grafx2")

The rest LGTM!  Feel free to push a revised version in which you explain
a little bit the choice of linker/preprocessor options.

Thank you!

Maxim