Thursday, August 17, 2006


Spike's Circus is game number 2 from Vectorzoa stable. (if you're a programmer that is, since programmers always count from 0! (See the Limited Edition Serial numbers for proof.) Logo was game 0, Star Sling was 1. As Vectrex collectors may be aware Star Sling was especially written to fit within the size of ROM that programmers had to use back in 1982. This size used was exactly 4KB or 4096 bytes. Most original GCE games were 4K with a few stretching to the extravagance of 8K. The Vectrex can address a maximum of 32K of on cart memory. Thanks to clever work by John Macallan this can be spilt between extra ROM and RAM. Spikes Circus uses 8K of onboard RAM, (the rotated clubs are pre-rendered to the RAM on boot, the side view of Spike's Unicycle is rendered in real time, and the top down view of the cycle on the tightrope is pre-loaded into ROM). The rest of the RAM is used to quickly access level gradients and heights for convenience. This leaves 24KB of potential ROM space to use for the game. Spike's Circus uses exactly 22,222bytes without any contrivance or artificial padding in the source code. Why 22,222? Well because it's game number 2 of course! :)

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