Art is Art and Water is Water

October 1, 2010

September Game: Coin Op

Filed under: Month Games — foone @ 9:48 am

Coin Op screenshot: Space ships and bullets
I was working on this right up to midnight on September 30th, but here it is: A coin-op shmup using tyrian sprites!

Code-wise, this one is very similar to Space Resistance, my august game. (Though I didn’t get as crazy with dumping invisible “thinker” objects into the draw queue this time). Nothing horribly special here, though I did have a neat idea for a color-shifting scrolling background (The current one is always that color, though it does scroll) that I never got a chance to implement. I did make use of the new PyGame microframework that I developed last month, and it worked beautifully. A few tweaks at the beginning and it stayed out of my way and provided some handy bits like easy screen scaling (The above screenshot is from running at 2X scale, and during development I was playing at 3X scale) and all the standard PyGame setup crap that never changes (at least for 2D games. OpenGL is trickier).

Gameplay-wise, it’s a pretty straightforward shmup. Enemies have Dark Stars-style random movement and shooting, your weapon repeats as long as you hold it down, and enemies randomly drop powerup crystals on death. Powerups upgrade your weapon so it shoots more bullets at once, and once you hit level 5 enemies start dropping coins which can be collected for a bunch of points. You’ve got one hit point, but if you have a powerup you’ll lose it instead of dying.

The enemy count starts at 10 and goes up for every stage beaten (all enemies onscreen defeated) or every minute that passes. Each stage is a random assortment of 4 enemy types (I planned to have it start with the easy ones and increase the proportions of stronger ones as stages go on, but ran out of time). There’s no boss or end, it’s just a survival game (it gets hard, fast!), aiming for highest score.

The real gimmick of the game is that it actually is a coin-operated arcade game. I bought a coin acceptor off ebay, stuck in a plastic box, and hooked up a microcontroller to the coin-accepted switch. This is the result. It communicates with the game over USB-serial, and the game won’t let you play until you pay 25-cents. If you want to get far, you need to shovel in quarters since it’s (sort of) a 1-hit-kill game and you have as many lives as you’ve paid in quarters.

Finally, the weirdest thing about the boringly named Coin Op: It has sound! (OK, maybe that’s only weird for foone-games) I created a bunch of 8-bit sound effects with the awesome sfxr project and dropped them in. (I see that playing sound with PyGame is surprisingly easy, now that I’ve finally tried it)


1 Comment »

  1. […] Coin Op […]

    Pingback by Game Inventory « Art is Art and Water is Water — November 1, 2010 @ 8:47 am

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