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A QTADS port to the BlackBerry PlayBook tablet

The BlackBerry PlayBook tablet is not a natural platform for interactive fiction. Nevertheless, it is possible to play TADS games, including those with graphics, using this port of Nikos Chantziaras' QTADS to the PlayBook. QTADS is an interpreter for TADS2 and TADS3 games, which supports graphics and hyperlinks. The playbook version has many limitations compared to the desktop version of QTADS, and the program is not entirely stable. Nevertheless, it uses exactly the same interpreter as QTADS, which is implemented in C, so it's complete and reasonably fast.

This is a 'thin port', which is to say, I've modified the original program as little as I had to, to make it run on the PlayBook. The user interface is desktop-like — same menus, same scrollbars, same dialog boxes — and all user input comes from the (virtual) keyboard. I've adjusted the sizes of the user interface elements, where practicable, to make them a better fit for finger-poking operation. But, on the whole, it's the same program as the desktop version of QTADS.

Changes from desktop version

  • As far as possible, there are no double-click operations. For example, to select a new folder in the file-open dialog box, a single click is all that is necessary. The PlayBook screen is not very sensitive to double-clicks.
  • The file-open and file-save dialog boxes fill the whole screen, and do not attempt to display a tree. The usual Qt tree view does not work very well on small screens.
  • The 'home' directory — where the file dialog boxes look in the absence of any other information — is the PlayBook shared media directory, not the current working directory. On the PlayBook, current directory is an unhelpful concept, so far as the end user is concerned.
  • By default, the open-file dialog box is displayed when the program starts. This behaviour can be turned off in the settings menu.

Limitations

  • There is no audio support, and there is unlikely ever to be. Sorry, but the way QTADS handles audio is not really compatible with mobile devices, and the entire implementation would need to be rewritten. It's just too much work for little gain.
  • The Settings dialog box is very fiddly to use on a small screen, particularly the little arrows for altering numeric values. It does work, but you might have to poke at it with the edge of a fingernail.
  • The biggest useability problem is that no line editing is possible. If you make a typing mistake at the beginning of a line, you get to rub it out (character by character) and start again. This is because the BlackBerry virtual keyboard simply doesn't have any editing keys, and there is no way to change the keyboard layout. The impoverished keyboard is a frequent complaint of BlackBerry owners, so maybe things will improve with a later version of the firmware.
  • QTADS occasionally hangs or crashes. It's hard to debug problems like this on a mobile device. Save your progress regularly.

Screenshots

Here are some more screenshots of the program in action.
The virtual keyboard is more useable with the tablet in landscape mode, but less of the screen is available for text.
QTADS can even play 'big' TADS games, like Macrocosm, on the PlayBook. However, the small screen of the PlayBook means that grapics-intensive games can be awkward to use.

Technical notes

QTADS is based on the Qt user interface library, which has been ported to the BlackBerry PlayBook. Most of the work of this port has been in packaging the code in BlackBerry format, providing new file-open/file-save dialog boxes, removing program features that either don't work or make no sense on the PlayBook, and tweaking the user interface element sizes and positions. There were many fairly trivial changes, such as modifying the code to use application-provided icons for the menu items, rather than system icons (since there are none on the PlayBook). However, the TADS interpreted code compiled cleanly with no modifications necessary. Which was nice.

Downloads

I won't be making my QTADS port available on the BlackBerry AppWorld site, because the administrators require far more personal information than I'm prepared to supply, just to give away my software for free. Anybody who is interested can download the application (click here). And side-load it using the DDPB utilities. A link to DDPB, and instructions for using it, are available here.
Copyright © 1994-2013 Kevin Boone. Updated Feb 08 2013