Implicit constructor parameters

You need to drop the parens

class GameScreen(val game : Game)(implicit val batch: SpriteBatch, implicit val world:    World, implicit val manager: AssetManager) extends Screen {

  val camera : OrthographicCamera = new OrthographicCamera

  createOpenGLStuff()
  createMap //this works

  def createMap(implicit w : World) : Unit = 
  {
  }

However, the createMap method has to perform some side-effects, so calling it without parens isn't really a good thing.

I suggest changing to:

def createMap()(implicit w : World) : Unit = {
  ...
}

This way, you get to maintain the original calling syntax: createMap()

Also, you only need the implicit keyword at the beginning of the parameter list:

class GameScreen(val game : Game)(implicit val batch: SpriteBatch, val world: World, val manager: AssetManager) extends Screen {...}