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diff --git a/site/posts/DiscoveringCommonLisp.org b/site/posts/DiscoveringCommonLisp.org deleted file mode 100644 index 479f76c..0000000 --- a/site/posts/DiscoveringCommonLisp.org +++ /dev/null @@ -1,261 +0,0 @@ -#+BEGIN_EXPORT html -<h1>Discovering Common Lisp with <code>trivial-gamekit</code></h1> - -<p>This article has originally been published on <span class="time">June 17, -2018</span>.</p> -#+END_EXPORT - -I always wanted to learn some Lisp dialect. -In the meantime, [[https://github.com/lkn-org/lykan][lykan]] —my Slayers Online clone— begins to take shape. -So, of course, my brain got an idea: /why not writing a client for lykan in some -Lisp dialect?/ -I asked on [[https://mastodon.social/@lthms/100135240390747697][Mastodon]] if there were good game engine for Lisp, and someone told me -about [[https://github.com/borodust/trivial-gamekit][trivial-gamekit]]. - -I have no idea if I will manage to implement a decent client using -trivial-gamekit, but why not trying? -This article is the first of a series about my experiments, discoveries and -difficulties. - -The code of my client is hosted on my server, using the pijul vcs. -If you have pijul installed, you can clone the repository: - -#+BEGIN_SRC bash -pijul clone "https://pijul.lthms.xyz/lkn/lysk" -#+END_SRC - -In addition, the complete project detailed in this article is available [[https://gist.github.com/lthms/9833f4851843119c966917775b4c4180][as a -gist]]. - -#+TOC: headlines 2 - -#+BEGIN_EXPORT html -<div id="history">site/posts/DiscoveringCommonLisp.org</div> -#+END_EXPORT - -* Common Lisp, Quicklisp and trivial-gamekit - -The trivial-gamekit [[https://borodust.github.io/projects/trivial-gamekit/][website]] lists several requirements. -Two are related to Lisp: - -1. Quicklisp -2. SBCL or CCL - -Quicklisp is an experimental package manager for Lisp project (it was easy to -guess, because there is a link to [[https://quicklisp.org/beta][quicklisp website]] in the trivial-gamekit -documentation). -As for SBCL and CCL, it turns out they are two Lisp implementations. -I had already installed [[https://www.archlinux.org/packages/?name=clisp][clisp]], and it took me quite some times to understand my -mistake. -Fortunately, [[https://www.archlinux.org/packages/?name=sbcl][sbcl]] is also packaged in ArchLinux. - -With a compatible Lisp implementation, installing Quicklisp as a user is -straightforward. -Following the website instructions is enough. -At the end of the process, you will have a new directory ~${HOME}/quicklisp~, -whose purpose is similar to the [[https://github.com/golang/go/wiki/SettingGOPATH][go workspace]]. - -Quicklisp is not a native feature of sbcl, and has to be loaded to be available. -To do it automatically, you have to create a file ~${HOME}/.sbclrc~, with the -following content: - -#+BEGIN_SRC common-lisp -(load "~/quicklisp/setup") -#+END_SRC - -There is one final step to be able to use trivial-gamekit. - -#+BEGIN_SRC bash -sbcl --eval '(ql-dist:install-dist "http://bodge.borodust.org/dist/org.borodust.bodge.txt")' \ - --quit -#+END_SRC - -As for now[fn::June 2018], Quicklisp [[https://github.com/quicklisp/quicklisp-client/issues/167][does not support HTTPS]]. - -* Introducing Lysk - -** Packaging - -The first thing I search for when I learn a new language is how projects are -organized. -From this perspective, trivial-gamekit pointed me directly to Quicklisp - -Creating a new Quicklisp project is very simple, and this is a very good thing. -As I said, the ~${HOME}/quicklisp~ directory acts like the go workspace. -As far as I can tell, new Quicklisp projects have to be located inside -~${HOME}/quicklisp/local-projects~. -I am not particularly happy with it, but it is not really important. - -The current code name of my Lisp game client is lysk. - -#+BEGIN_SRC bash -mkdir ~/quicklisp/local-projects/lysk -#+END_SRC - -Quicklisp packages (systems?) are defined through ~asd~ files. -I have firstly created ~lysk.asd~ as follows: - -#+BEGIN_SRC common-lisp -(asdf:defsystem lysk - :description "Lykan Game Client" - :author "lthms" - :license "GPLv3" - :version "0.0.1" - :serial t - :depends-on (trivial-gamekit) - :components ((:file "package") - (:file "lysk"))) -#+END_SRC - -~:serial t~ means that the files detailed in the ~components~ field depends on -the previous ones. -That is, ~lysk.lisp~ depends on ~package.lisp~ in this case. -It is possible to manage files dependencies manually, with the following syntax: - -#+BEGIN_SRC common-lisp -(:file "seconds" :depends-on "first") -#+END_SRC - -I have declared only one dependency: trivial-gamekit. -That way, Quicklisp will load it for us. - -The first “true” Lisp file we define in our skeleton is ~package.lisp~. -Here is its content: - -#+BEGIN_SRC common-lisp -(defpackage :lysk - (:use :cl) - (:export run app)) -#+END_SRC - -Basically, this means we use two symbols, ~run~ and ~app~. - -** A Game Client - -The ~lysk.lisp~ file contains the program in itself. -My first goal was to obtain the following program: at startup, it shall creates -a new window in fullscreen, and exit when users release the left button of their -mouse. -It is worth mentioning that I had to report [[https://github.com/borodust/trivial-gamekit/issues/30][an issue to the trivial-gamekit -upstream]] in order to make my program work as expected. -While it may sounds scary —it definitely shows trivial-gamekit is a relatively -young project— the author has implemented a fix in less than an hour! -He also took the time to answer many questions I had when I joined the -~#lispgames~ Freenode channel. - -Before going any further, lets have a look at the complete file. - -#+BEGIN_SRC common-lisp -(cl:in-package :lysk) - -(gamekit:defgame app () () - (:fullscreen-p 't)) - -(defmethod gamekit:post-initialize ((app app)) - (gamekit:bind-button :mouse-left :released - (lambda () (gamekit:stop)))) - -(defun run () - (gamekit:start 'app)) -#+END_SRC - -The first line is some kind of header, to tell Lisp the owner of the file. - -The ~gamekit:defgame~ function allows for creating a new game application -(called ~app~ in our case). -I ask for a fullscreen window with ~:fullscreen-p~. -Then, we use the ~gamekit:post-initialize~ hook to bind a handler to the release -of the left button of our mouse. -This handler is a simple call to ~gamekit:stop~. -Finally, we define a new function ~run~ which only starts our application. - -Pretty straightforward, right? - -** Running our Program - -To “play” our game, we can start the sbcl REPL. - -#+BEGIN_SRC bash -sbcl --eval '(ql:quickload :lysk)' --eval '(lysk:run)' -#+END_SRC - -And it works! - -** A Standalone Executable - -It looks like empower a REPL-driven development. -That being said, once the development is finished, I don't think I will have a -lot of success if I ask my future players to start sbcl to enjoy my game. -Fortunately, trivial-gamekit provides a dedicated function to bundle the game as -a standalone executable. - -Following the advises of the borodust —the trivial-gamekit author— I created a -second package to that end. -First, we need to edit the ~lysk.asd~ file to detail a second package: - -#+BEGIN_SRC common-lisp -(asdf:defsystem lysk/bundle - :description "Bundle the Lykan Game Client" - :author "lthms" - :license "GPLv3" - :version "0.0.1" - :serial t - :depends-on (trivial-gamekit/distribution lysk) - :components ((:file "bundle"))) -#+END_SRC - -This second package depends on lysk (our game client) and and -trivial-gamekit/distribution. -The latter provides the ~deliver~ function, and we use it in the ~bundle.lisp~ -file: - -#+BEGIN_SRC common-lisp -(cl:defpackage :lysk.bundle - (:use :cl) - (:export deliver)) - -(cl:in-package :lysk.bundle) - -(defun deliver () - (gamekit.distribution:deliver :lysk 'lysk:app)) -#+END_SRC - -To bundle the game, we can use ~sbcl~ from our command line interface. - -#+BEGIN_SRC bash -sbcl --eval "(ql:quickload :lysk/bundle)" \ - --eval "(lysk.bundle:deliver)" \ - --quit -#+END_SRC - -* Conclusion - -Objectively, there is not much in this article. -However, because I am totally new to Lisp, it took me quite some time to get -these few lines of code to work together. -All being told I think this constitutes a good trivial-gamekit skeleton. -Do not hesitate to us it this way. - -Thanks again to borodust, for your time and all your answers! - -* Appendix: a Makefile - -I like Makefile, so here is one to ~run~ the game directly, or ~bundle~ it. - -#+BEGIN_SRC makefile -run: - @sbcl --eval "(ql:quickload :lysk)" \ - --eval "(lysk:run)" - -bundle: - @echo -en "[ ] Remove old build" - @rm -rf build/ - @echo -e "\r[*] Remove old build" - @echo "[ ] Building" - @sbcl --eval "(ql:quickload :lysk/bundle)" \ - --eval "(lysk.bundle:deliver)" \ - --quit - @echo "[*] Building" - -.PHONY: bundle run -#+END_SRC |