Spacebar for mouse control

[migueldeicaza]

On the edges, we should trigger a timer to keep sending the event, so it can continue sending arrow keys indefinitely.

I suspect that to get this behavior for free, the UITextInput protocol that currently creates a "virtual" input line needs to be modified to return a more accurate representation of what is on the screen. The issue of course is that the "virtual" input line is needed because we do not really know what the underlying application thinks about the screen, nor where the boundaries are (ie, "miguel@macpro$ _" is a prompt to a human, but to UITextInput, it could be a tasty piece of string to be walked over.