Having seen the Amstrad version of this brilliant utility, looking at the preproduction Spectrum version provided by Incentive was like greeting an old friend. It has so many features that we've decided to give it a two-part review, the second part coming next month when we hope the finished product will be ready to fill in a few gaps. One gap in GAC as yet is the amount of memory that will be available to you, and that should be in the region of 22/23K according to Incentive. The 'true' size of an adventure written using GAC will be much larger as the program incorporates compression routines. By way of illustration, Incentive's own Ket Trilogy will fit comfortably into the GAC system and leave several K left over, and that's not a tiny adventure.
GAC is menu driven, the opening screen allowing single-key access to options such as Nouns, Verbs, Graphics, Messages and so on. You'll need to do a considerable amount of planning before attempting an adventure, and we'll deal with the way to approach this next time. For now we'll try to familiarise you with some of the features.
The text side deals with full-sentence input of nouns, verbs and adverbs. The parser picks each out, so the DROP THE ELEPHANT CAREFULLY and CAREFULLY THE ELEPHANT DROP would both be understood. A 'Quickstart' file is provided and that enters all the common commands for you, like NORTH, SOUTH, GET, WHAT NOW? and ending and saving routines.
Printing the location description, linking it to a picture number (if any) and interpreting the input are fairly simple, but you'll have to be careful with the three types of conditions which control what goes on in the adventure. High priority conditions happen immediately after the location description is printed, before any player input, so that if you arrive in the bull-ring while carrying the red handkerchief the death routine is called up. Local conditions happen in that location after the player's input, assuming the input wasn't an acceptable movement command. For instance, if you throw the axe it kills the dwarf, and if you don't throw the axe the dwarf kills you. Finally come the more routine low priority conditions, such as acting on inputs like GET, SCORE and so on.
A typical way of entering a low priority condition would be: IF (VERB 8 AND NOUN 1 AND CARR 5) DROP 5 OKAY END. That simply means that if the player typed in DROP LAMP, which you've designated as verb 8 and noun 1 respectively, and he's carrying the lamp (object 5) then drop the lamp, print Okay and wait for the next command. If you wanted to drop the lamp to produce an explosion that kills the player then instead of OKAY END you might enter MESS 216 EXIT END. Message 216 would be the message explaining what happens when the lamp's dropped and EXIT takes you out of the game. END tells the interpreter to stop there and not bother to look through the other conditions.
I'll look at how to approach the writing of an adventure using GAC next month. Meanwhile, if you were thrilled by The Quill then it's safe to say you'll be taken aback by the GAC. This all-in-one package will be the source of some impressive adventures in several month's time, I'm convinced of it.
The G in GAC stands well and truly for Graphics. The graphic creation mode of the package is very easy to use. These pictures were constructed very quickly indeed, as the time taken to familiarise yourself with its many facilities is short. You can edit graphics like everything else in GAC, continuously, adding and taking bits away right up until the final compilation. It's a bit like a word processor for graphic adventure games, really.
The full feature graphics editor includes ellipse, rectangle, dot, line, fill, shaded fill, and attribute fill. You can move the cursor one dot or eight dots at a time in skip or draw mode. By far the most powerful feature of the editor is the way it shows you the effects on attributes before your draw, making mistakes easily correctable. You can step back through the drawing, and edit out one line, colour or fill, as you wish, retaining the rest of the drawing intact.
If the graphic editor wasn't in the GAC it would still be a good drawing package, and that I think is the highest recommendation.