Saturday, March 26, 2016

Under the Hood: Introduction to the Nuts and Bolts of Nox Archaist

This is the first post in a series that will get into some of the technical architecture of Nox Archaist, below you'll find some information on the system requirements and details relating to the design of the game.

Platform
  • Runs on any 128k Apple IIe or later system
  • Physical machines and modern emulators are supported
  • Current game testing is being done on a physical Apple IIe and in AppleWin


Design Details
  • Coded entirely in 6502 assembler with no construction sets used
  • Started in LISA, switched to cross assembler (SBASM) with automated dev process
  • Architecture supports over a thousand unique tiles
  • Single mode Hi-Res graphics in a tile-based architecture
  • Draw-draw animation with page flipping
  • Screen scrolling and page flipping for map movement
  • Custom bootloader with RWTS only DOS component loaded
  • All disk I/O via calls to RWTS



2 comments:

  1. Ah, very cool you're skipping DOS to give you the most disk space. I've heard that people are able to get 157K per disk instead of 140.

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  2. Thanks for your comment. You’re correct, using a custom boot loader to skip DOS allows more disk space to be used for the game itself. DOS is also a memory hog. By skipping DOS we also free up 60%+ more main memory for game code.

    Customer boot loader were used in most large scale commercial games made in the 1980s. I found the research and experimentation to get a boot loader working for Nox Archaist to be one of the most fun parts of the projects so far.

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