Game of the Month

ARENA RACER

by JAMIE SUTHERLAND

Arena Racer is 15 scrolling levels of fiercely challenging maze action. Can YOU fly a speeding Huntercraft through labyrinthian caverns and avoid getting blasted apart by all those laser Cannons? This unusually fast BASIC program works on all Atari computers of any memory size.

Uh-oh! There's an intergalactic war on and you got shot down onto a rather nasty planet. The local enemy warlord gets plenty of entertainment from Elite Fighter Pilots like you-when they're unlucky enough to fall into his hands. (Yes, you are a rocket ace. You only lost that last dogfight because you were so vastly outnumbered.)
   You are tossed into an unarmed Huntercraft and sent down to a horror known as... the Arena! This Arena is a vast maze of caverns. On each of the caverns' 15 levels, you must collect four glowing orbs, which have been hidden and protected. But. ..as you fly among the twisting walls of the Arena, scores of deadly laser cannons are firing at you.
   If you complete the fifteenth level you get to start over again, with even faster action. Your only reward is survival!! For you see, you are operating under a strict time limit. If you do not complete a level in time, your Hunter-craft will disintegrate. HAHAHAHA!! (We told you it was a rather nasty planet.)

INSTRUCTIONS
Type in Listing 1, check it with TYPO II and SAVE a copy before you RUN it.
   When playing, you start with four Huntercraft and win a bonus ship after every five levels you complete. Maneuver in any direction with the joystick, even diagonally. Pick up an orb simply by moving over it.
   Your joystick trigger is the Panic Button. As long as you hold it down, your Huntercraft stays motionless and is invulnerable to laser hits. The good thing about the Panic Button is that it never runs out of operating energy, you can always use it.
   The bad thing about the Panic Button is that it makes your time limit run out faster... Is Arena a hard game to play? All I can say is that I wrote it and I've never gotten higher than 12 of the 15 levels.

PROGRAM TAKE-APART
Initial setup is done in Lines 1000 to 1070. This includes POKEing in the machine language subroutine and character definition.
The major action is found in lines 10 to 70:

10    Produces timer sound and checks for OUT OF TIME
15    Draws current screen and checks for PANIC BUTTON
20    Shuts off timer sound and checks JOYSTICK
30    BOOLEAN LOGIC determines joystick dirction
40    Checks to see if you hit something
50-60 If path is clear, lets you move in that direction
70    Go back for more

Lines 80 to 280 check what character your ship has hit. The appropriate action is then taken-pick up orb, be destroyed by laser, etc.

CUSTOM SCREEN SETUP
The more adventurous of you can create your own screens. It's not exactly easy, but it can be done after some trial and error.
   The Arena is made up of an array of 70 X 70 characters. DATA for the levels is contained in lines 6000 to 6290.
   Every second line, beginning at 6000, contains 70 characters arranged in a pattern which makes up the walls, spaces and cannons. Every second line beginning at 6010 contains DATA for placing the four orbs. You may manipulate this DATA as you wish. The only restriction is that first five and the last five characters in each of the screen DATA statements must each be an "A."
   The screen DATA characters represent:

A     Solid line of wall characters
B     Solid line of open spaces
C,D,F 3 different patterns of walls and spaces
E,G   2 patterns of walls and spaces that also include laser cannons

   Placement of the orbs is more difficult. The four orbs must not be in the path of any laser, on or off the small viewscreen, or they will be destroyed. To determine where you want each orb, multiply the vertical coordinate by 70, add the horizontal coordinate, and place the result in the DATA line immediately following the screen DATA line. This should be done with each of the four orbs for each screen.
   Below is an example of a customized first screen. Line 6000 is the screen data, and line 6010 is the placement data for the four orbs.

6000 DATA AAAAABBBBBBEB
BBBBBBEBBBBBBBEBBBBBEBB
BBBBBEBBBBBBBEBBBBBBBEB
BBBBBBAAAAA
6010 DATA 672,1338,2075
,3043

   The only way to test your Arena and make sure that everything is working right is to RUN the game. If you want to test a higher level, change L = 0 in line 1070. L is the current level minus one. So L =7 would start you out at level 8.
   Now you should have enough to get started. Have fun creating your own Arenas.

Jamie Sutherland is a high school junior from Bend, Oregon. His first hands-on computing experience was with the old Sinclair ZX-80 of popular Antic game programmer JD. Casten. You'll see Jamie's vast scrolling maze game, "Valiant," in Antic soon.

Listing 1.  ARENA.BAS Download