Well, Moonsweeper is a pretty cool game in the first place. Mad props to the programmer at Imagic that cobbled this one up. The Atari 2600 is an amazing machine when you see the stuff some people had managed to squeeze out of it. (I believe the guy who designed the hardware was shocked when he saw the Night Driver game in action. The system was designed for Combat and Air Sea Battle and little else.)
Moonsweeper is impressive because it is one of the few 3-D perspective games for the 2600 and it is one of the more successful ones. Technically, it is a simple vertical shooter, no different from, say, Space invaders or Galaxian. However some primative scrolling and background effects fool the eye into thinking it is 3-D. And by background effects, I naturally mean the planet surface with the alternating dark/light colors giving a sense of forward movement. This effect immediately brought Space Harrier to my mind. However, the limitations of the hardware make it impossible to impliment the flying effect. The Harrier is stuck moving back and forth along the bottom of the screen. We'll just have to live with it.
This is mostly just a cosmetic hack instead of a deeper, gameplay altering hack If possible, it would be great to alter the gameplay to better reflect the arcade game. But a cosmetic hack is a good start. It is challenging trying to get the 2600 to mimic the graphics of the arcade game and mapping it onto the play elements. I am rather proud of the robot lander that skids around on the surface. My previous design looked too blocky but then I deleted two pixels, one under each wing, and it was a dramatic improvement.
If I ever get to the point of altering the play code, I would do a couple things. Like start on the planet surface. In fact, keep the surface present throughout the game, like the arcade. I would probably turn the space phase into a boss stage, but this will be a tricky item for a total newbie like myself.
Upon reflection, I am thinking of calling this hack Moon Harrier in honor of the hacked game it's based on. Anyway, here are some screen shots.