| ★ AMSTRAD CPC ★ GAMESLIST ★ THE SATAN BLINDER (c) INTERFACE PUBLICATIONS ★ |
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With our second Adventure, we break new ground. This program takes place in a deserted medieval castle in France. The name of the castle is real, all else is imaginary. Puzzles There are a number of ways you can increase the level of interest in an Adventure. One way is to have puzzles which the player must solve before continuing. In this program, the puzzle concerns a dwarf, who is going to make sure that if you stumble into the room where he lives, you will not be able to leave, unless you manage to hit the one thing that will enable you to continue. There are two locked doors, with keys a long way away from the relevant rooms, and as you've experienced before, you must have the right key for the right lock. Two-Word Sentences The main difference between this Adventure and the previous one, is that in this one the computer is given the facility of understanding English — or at least appearing to do so. The computer is programmed to recognize and act on two-word sentences. The two words must be a verb first, followed by a noun. The computer, for example, can understand the instruction GO NORTH (or even RUN NORTH, MOVE NORTH, CLIMB NORTH, or WALK NORTH). You'll find it is far more satisfying to “talk” to your computer in this way than it is to communicate simply by touching a key. As was pointed out at the start of the book, some of the pleasure of Adventure programs comes from trying to work out which words it will understand, and which it will reject. All the objects you encounter within the chateau can be manipulated — at least to the extent of being picked up or put down. Some objects (such as the MYSTIC SCROLL) can be read and others can be drunk. As you can tell from this, the vocabulary handling is quite extensive. You have six “attributes”. You'll see that these are slowly reduced as you make your moves. You must find the exit from the chateau before any of them is cut right down to zero. Vocabulary Handling The most important idea introduced in this program is the vocabulary handling which, I hope you'll agree, adds a completely new dimension to the program. First, the variable KW (which stands for "key word”) is set to zero in line 420. If KW becomes equal to one, then the computer has recognized a phrase it can act on. Line 430 accepts the answer to the question “What do you want to do?”. Line 470 sets M equal to the length of the player's input. It cycles through, adding blank spaces, until it is seven characters long. Line 480 then strips off the first three letters. In common with most Adventure programs, only the first three letters of a command must be entered, so WAL will do for WALK, and FIG for FIGHT. Three letters have been found to be sufficient to avoid ambiguity, and it is good to allow the player to simply enter three letters, rather than the whole word, if that is what he or she wants to do. Line 490 detects the word HELP and gives a cryptic, but useful, reply, then returns to the beginning of the major handling loop in this program. Line 500 allows the player to QUIT and sends action to the routine which terminates the program, starting a line 2650. The next section of the program is the most important part of the vocabulary handling routine. Line 520 goes through the player input, character by character, looking for the first space which it knows should occur between words one and two (as between RUN and EAST, or GET and DIAMOND). Having found it, the computer sets C$ equal to the first three letters of the second word, to go with its BS which it earlier set equal to the first three letters of the first word. If it finds that the first letter of C$ is not a space it knows the player's input was two words, so goes to line 570 to continue processing the input. Line 530 continues the scan through the input. The computer comes to line 540 if the scan through the input finishes, and the gap between two words has not been found, or it discovers that the first character of C$ is a space. The RND in line 540 chooses between two replies to tell the player a new input is needed, and then goes back to get a new input. Here, now, is the heart of the computer's ability to “understand” the player's wishes. Line 570 checks to see if the player is in room 8 or in room 34, and if not, jumps to line 600. These two rooms are the ones which are locked at the start of the game, and it is important to check to see whether or not they are still locked before the program continues. Even if the room is locked, it may contain a monster who feels like a fight, and this takes precedence over the need to unlock the door before proceeding. Look carefully at line 580. It allows the following words to be accepted: STA — for STAB Any one of those will be accepted, and acted upon. You can see that a player who does not know, in advance, which words the computer will accept, should easily find one or two which will allow the machine to carry out his or her wishes. Line 590 is only acted on if the contents of the room (the seventh element of A array) is a value greater than 98. This means the door is locked. If this is true, and the BS part of the string does not contain UNL (as n UNLOCK), the computer will just point out that "The doors are locked” and then go back to the start of the major handling routine for a new input. Line 600 is a repeat of line 580, but this version of it is reached if the player is not in a room with locked (or potentially locked) doors. You'll see, at the end of line 600, that KW (the variable standing, you'll recall, for "key word”) is set equal to 1, meaning a word has been recognized. Finding a word meaning "fight” the computer sets KW equal to 1, then goes to the subroutine from line 1510 where the fight takes place. Line 610 accepts the words for movement, which are GO, MOVE, CLIMB, RUN, and WALK. It goes to the subroutine from 780, where the actual moves between rooms are made. Line 620 allows the player to pick up things with TAKE, GET, STEAL, and LIFT. The desire to get rid of things is recognized by line 630, which accepts DROP, PUT, THROW, and BREAK (and when it reaches the subroutine from line 1240, prints out a message — such as WITH A CRASH, THE VASE SMASHES AGAINST THE WALL - which is related to the word you chose to use when making your input. Line 640 is used when you wish to UNLock the door, 650 if you are OPEning something (such as the chests which litter the place), 660 for REAding, 670 for DRInking or SWAllowing, and line 680 for ... But I'm not going to tell you. It was hinted at a little earlier, and I'm not going to repeat the hint. Far better than you have the pleasure of working it out for yourself. You'll recall that there was a section of code which rejected single word inputs. You'll also recall that the variable KW was to be set to 1 if a word the computer could understand was found. If the computer finds, at line 690, that KW is not equal to zero, then it knows all is probably well. If it does not, the player gets to the next section if he or she has entered a two-word phrase, but it is not one which the computer can understand. All obscene entries, often the input of very frustrated players, end up here. The computer chooses one of the three replies, each of which uses the phrase entered by the player, echoing back any rude words. After a pause the program returns to the beginning of the major handling routine. All other parts of this program are simply developments of ideas discussed earlier. You will find that, with the knowledge you've gather so far in your reading, you should have little trouble in working out how each section works. The map is relatively complicated, as you can see. I suggest you try very hard not to look at it, until you've attempted to map the dungeon yourself. Amstrad Omnibus |
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Page créée en 832 millisecondes et consultée 1384 fois L'Amstrad CPC est une machine 8 bits à base d'un Z80 à 4MHz. Le premier de la gamme fut le CPC 464 en 1984, équipé d'un lecteur de cassettes intégré il se plaçait en concurrent du Commodore C64 beaucoup plus compliqué à utiliser et plus cher. Ce fut un réel succès et sorti cette même années le CPC 664 équipé d'un lecteur de disquettes trois pouces intégré. Sa vie fut de courte durée puisqu'en 1985 il fut remplacé par le CPC 6128 qui était plus compact, plus soigné et surtout qui avait 128Ko de RAM au lieu de 64Ko. |
