master:
dev:
Space Invaders is a game written by Mathias Bockwoldt in Javascript (ECMAScript 2018) without any frameworks for the it-talents.de competition September 2019 sponsored by Airbus.
The latest version on the master branch can be played here: frunit.itch.io/space-invaders
To run the game locally, you need to serve this directory (and subdirectories)
in a local web server. You could use some Javascript server or if you have
Python 3 installed, run python3 -m http.server. Of course, you can also copy
the files to some Apache or nginx instance.
In any case, point your browser to the index.html via the server. If you try
to open the file in the browser directly (without server), the security
restrictions of moderns browsers will prevent code execution.
The classical alien monsters once again attack from above and you have to defend planet Earth. You may play alone or ask a friend to control a second fighter.
There are two major differences to the original game. There are several different levels. If you manage to beat the all, the first level will load again, but with more difficult enemies! Also, enemies have a certain chance to drop goodies (or power-ups) that will improve your fighter for a few seconds. But beware of the dangerous fake goody that will kill you!
The game needs a keyboard, so it will not work on touch-only devices!
The background was generated using the Space Background Generator by Deep-Fold.
The game is written in an object-oriented way. The master game object handles a screen and the current stage. The stages should work without any screen, modifying objects following certain rules. The objects can be sent to the screen for rendering. The stages are:
start- The start displayengine- The actual gamehighscore- The highscore
The game has three global objects, that are:
game: The actual game, holding the game stages and the screen.input: Input management that is requested by the stages.resources: Organizes graphics used by the screen. This is defined globally to be able to load graphics before the game is initialized.
The source code documentation is compatible with JSDoc. After installation of JSDoc, you can build the documentation using:
jsdoc . --readme readme.mdThe documentation root will be in the file ./out/index.html.
Apparently, automatic testing of a Javascript game ment for the browser is difficult. I tried to separated browser-specific code as much as possible from browser- independet stuff. The independent things can be tested automatically in node.js. For this, I use QUnit. QUnit can in principle also test browser content, but this doesn't work automatically and involves the user opening a specially prepared test page. This, in turn, might be possible using a headless browser with some modifications, but that was too much effort for this competition project.
Due to these limitations, Screen is not covered by tests. I created a "fake"
class to replace the real Screen as closely as possible in the tests. The
class to import is chosen automatically at runtime depending on the presence of
the window object (which is only present in browsers).
For testing, you need the following (assuming that an up-to-date version of node.js and npm are installed). It will also run a code linter, ESLint, as a kind of simple static code analysis.
npm install
npm testIssues, bugs, and proposals can be sent using the Github issue tracker
I don't keep a central to-do list, but write them as comments directly into the
files. On Linux, you can retrieve them using grep.
grep TODO *.js # These are *must* to-dos
grep MAYBE *.js # These are features I might include later