node-sdl ( Simple DirectMedia Layer bindings for node.js )

0. Installation

Currently, installation is finicky and largely depends upon my specific system for now. A future release is planned to make this process better. If you want to get it working, you need to have the dylibs mentioned in bindings.gyp under /usr/local/lib. (this includes the main SDL2 dylib, SDL2_ttf, and SDl2_image)

If you have those libraries, and clone node-sdl, you can build it with

 node-gyp configure build 

1. Usage

As a general rule, these bindings adhere to the following conventions.

• SDL structs are wrapped at the base level of the bindings. If you want a Window, it will be under sdl.Window.
• Structs that you would normally pass to various functions are instead wrapped as objects with prototype functions, and are created with the new keyword. As an example, instead of doing something such as

  sdl.GetWindowWidth(window)

  , you would instead do

  var window = new sdl.Window(...); window.getWidth()

  .
• Constants, enums, etc. are split up into various namespaces below the base namespace, based on where the underscores are in their name. This roughly translates

  SDL_WINDOWPOS_CENTERED

  into

  sdl.WINDOWPOS.CENTERED

  .
• Extensions to the base SDL API are under their own namespace. While you would find

  sdl.Window

  or

  sdl.Renderer

  , anything under the SDL_ttf library would be under

  sdl.TTF

  If you want to make a font, you would use

  new sdl.TTF.Font

  .

2. Specific usage

2.1 Initialization and Shutdown

Explaining the basics behind finding pieces of the SDL API is all well and good, but examples are still the best. So here is a quick and easy way to create a new window using node-sdl.

sdl.init(sdl.INIT.EVERYTHING); // Initialize all SDL subsystems.
var window = new sdl.Window("Test Window", sdl.WINDOWPOS.CENTERED, sdl.WINDOWPOS.CENTERED, 640, 480);
setTimeout(function() { sdl.quit(); }, 2000);

It's that easy. Though one thing to be aware of: in that example I declared a window in the global space. Because that is the only place it is referenced, once the script finishes (meaning after the call to setTimeout) there will be no more references to it. That means the window will get garbage collected sometime in the future. And because the bindings handle destroying SDL objects when the wrapping object gets destructed, that means the window will disappear, seemingly randomly. Make sure you keep a reference to all objects you want to persist somewhere, or you might find your window disappearing without warning.

2.2 Events

Currently, events are wrapped as a pure Javascript object. So trying to access properties of the event that don't exist for that event will give back undefined. You can determine the exact type of event by checking

event.type

just like in SDL. Same goes for all the other properties. If an event would have a key member, that will be in the Javascript object, etc.