Before we go any further, here it is: Vorple using Parchment to run a Z-machine story file created with Inform 7.
The preview is a recreation of the proof of concept from almost a year ago with only minor adjustments. The proof of concept used a custom two-word parser, but the preview runs on an actual interpreter with a proper library.
I’ve been able to include the feature I’ve wished for ever since I started playing IF: in the scrollback the previous turns are faded out so that the current turn stands out better. This makes it easier to see where to continue reading and less scanning with your eyes. A related feature is the addition of a smooth scroll animation to the bottom of the scrollback instead of an abrupt jump.
The big new thing is scrollback folding. If you enter an invalid command, the response is shown in a different style and hidden the next turn. The idea here is to keep the scrollback clean of noise so that only story-relevant content remains. Similarly any meta commands are displayed as notifications and not shown in the scrollback at all.
Note that this is mainly a tech demo and the behavior of these features will be later adjusted to fit.
In theory any feature from the Vorple library can be added to the story. The preview uses mainly images and tooltips, but there’s no reason it couldn’t play sounds or create UI buttons.
The interpreter will be fully backwards compatible with other story files (Z-machine only at the moment). Try for example Stephen Granade’s Fragile Shells. You get the same layout, current turn highlighting and smoother scrolling, although of course other features that require support from the story file aren’t available. (The status line is hidden and there are some glitches, most notably lockups if you try the in-game menus or when any time single-character input is required, but that’s all temporary.)
Not only that, but the Vorple-enhanced story files degrade gracefully to text-only versions. If you download the zblorb file and try it with an offline interpreter or with a non-Vorple installation of Parchment, you’ll get a text-only version of the same game (although not a very exciting one).
The story file can provide alternative content to multimedia features, showing text instead of images. Entire sections can be added or removed depending on the interpreter’s capabilities. In the non-Vorple version there’s a short explanation in the intro text that’s not in the Vorple version and so on.
As you can see from the preview, there are various smaller and larger issues that need to be ironed out. Internally things are bound to change radically as the related standards are still in a state of flux.
Most likely there will be one Undum-only release before a Parchment-compatible one, which will include the toolset for making stories with Inform 7.