Dragonfire

published by Tandy in 1984, running on Tandy Color Computer

type: action/reflex
genre: Fantasy, Action-Adventure
perspective: side view
player options: single player

languages: eng

Technical specs

hardware: Joystick,

display: raster

Editor note

Imagic wanted to to used the Coco 1's 128x192 graphics mode, which was limited to 4 colors. But they also wanted to use 8 colors, which required using 32x16 graphics mode. Their solution was to implement their experience of "racing the beam". On the Atari VCS, "racing the beam" was a reference to the VCS having no video frame buffer so programmers had to create machine code that calculated game logic in-between the machine code that that set colors on a pixel and executed according to the immutable timing of the TV's electron beam. And advantage to this difficulty is the ability to use as many colors as the programmer is willing to sacrifice from CPU cycles (There is a 56 color per scanline hardware limit but 2 colors are a practical limit and a 128 color palette hardware limit, but even these are surmountable). The Coco 1 had frame buffering to 'save' the programmer from such difficulties (tell the CPU what color a pixel is and the hardware automatically figures out when send it to the TV), but it also limited them. Such as having a fixed pallet for each video mode. Imagic overcame this limit by switching video modes up to 5 times per scanline. When a certain color was needed at a certain pixel, the mode that could provide it was used. And game logic once again was done in-between immutable timing of mode switching. So, 128x192x8, a mode that doesn't actually exist but that's no reason not to enjoy it in this game :) Later, clever programmers figured out how to extend this technique to get 320x200x256 with those 256 colors selected from a 24-bit pallet!

The Coco 3 altered the graphics hardware for the platform and broke this game. However, Imagic provided a patch so that Dragonfire could be played on a Coco 3.