The Let's Play Archive

Compute!'s Gazette

by Chokes McGee

Part 13: ManxomeBromide - maze editor!

What follows is a lightly edited version of the Crossroads II maze editor instructions. —MB


Crossroads II: Maze Editor

You've played "Crossroads II: Pandemonium." Now use the "Crossroads II Maze Editor" to modify the game. When you decide where to put the corridors, you control the tempo, difficulty, and danger of the game.

Crossroads is an exciting one or two-player game that's played on an unpredictable battlefield of corridors, sharp turns, and dangerously spacious pitlike areas where the phrase take cover has little, if any, meaning. With Maze Editor, you can modify or completely redesign the eight different mazes used by this frantic game. The maze editor wedges into Crossroads II, allowing you to create mazes interactively: Just draw your maze using a joystick and press a key to reenter the game and test your maze. If you find something wrong, just press RESTORE to return to the maze editor and change what you don't like. It's that easy.

Maze Editor offers several editing features: reverse, clear, copy, paste, undo, and save. When you save your mazes to disk, a whole new copy of the Crossroads program is saved along with them. This way, all you have to do is load the new version of Crossroads. You can have several versions of the game, all on the same disk.


Use "MLX," the machine language entry program found elsewhere in this issue, to type in Maze Editor. When MLX prompts you, respond with the values given below.

Starting address: C800
Ending address: CDC7

Be sure to save a copy to disk when you've finished entering the program. To install Maze Editor, enter

SYS 51200

Now, load and run Crossroads II.


SHIFT-R: Reverse maze
SHIFT-U: Undo editing changes
SHIFT-C: Copy current maze into paste buffer
SHIFT-V: Paste maze
CLR/HOME: Erase maze
F1: Previous maze
F3: Next maze
F5: Save new version of Crossroads with modified mazes
F7: Exit editor and return to Crossroads
Note: Undo restores the maze to the state that it was in when you last moved to that maze using F1 or F3, pasted to that maze using SHIFT-V, or saved the program using F5. Any editing changes made between these times can be undone with SHIFT-U.


To edit a maze, press RESTORE while Crossroads II is in demo mode (that is, while the words Crossroads II: Pandemonium appear at the top of the screen). The current maze number (1-8) appears in the upper right corner of screen. (The editor comes up with the maze that was on the screen when you pressed RESTORE.) Move through the eight mazes with the F1 and F3 keys.

Using a joystick plugged into port 1, move the white blinking cursor. Editing works the same as in the popular GAZETTE programs "Ultrafont +" and "Sprite Magic." To draw, press the fire button while on top of a space and move the joystick. Press the fire button while on top of a wall and move the joystick to erase. To move the cursor with out drawing or erasing, move the joystick without pressing the fire button. Mazes must be symmetrical, so everything drawn is "mirrored" to the right-hand portion of the screen (you can draw only on the left portion of the screen).

To quit edit mode and return to Crossroads, press F7. To save your new mazes, press F5. Enter a filename. A new copy of the Crossroads program with your mazes is saved to disk. You must choose a filename that is unique, as the maze editor does not offer a save-with-replace option. The save option saves only to disk device 8. You cannot save mazes to tape.


There are certain rules that you must follow when creating mazes. You must never leave a single isolated square on the screen. If an enemy creature beams into that space, the game locks up. You can't place a wall in the square where your player starts the game (and be sure to leave somewhere to go from this square). And finally, you must be sure that there are at least 40 or more blank spaces on the screen for enemy creatures to appear.

If you make a mistake in drawing your maze and Crossroads II lock's up, press RUN/STOP-RESTORE. Then type SYS 51200 to reinstall Maze Editor. Type RUN to start Crossroads II.

You can't determine the character or character color used to draw your maze—this is determined randomly by the program. Crossroads II always uses mazes 1-4 for levels 1-4. Mazes for level 5 and above are randomly chosen
from the eight mazes available. The program never chooses to use the same maze twice in a row.

Finally, Maze Editor works with Crossroads II only. It does not work with the original "Crossroads."


It's kind of a bummer that you need to SYS 51200 to activate the level editor, but we kind of need to activate it independently of the game itself (which has dibs on RUN). So, it'd be nice if we could give ourselves a reminder of how this works. If only there were a handy place to stick a 16-bit unsigned integer in a directory listing.

There is, as it turns out; we can lie about the file size. I could just go hex-edit the disk image again, but Chokes typed in a program to do exactly this from the issue that had Bagger in it early on in the thread, so I can use that to stamp this program with the entry point:

And this works just fine, though it does warp the file display just a little bit:

The disk display assumes, reasonably, that file sizes will cap out at three digits, since the whole disk is under 700 blocks. We, however, laugh at their conventions!