MiniDict3 Screen Compressor for Spectrum

The place for codemasters or beginners to talk about programming any language for the Spectrum.
Joefish
Manic Miner
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Joined: Tue Nov 14, 2017 10:26 am

Re: MiniDict3 Screen Compressor for Spectrum

Post by Joefish » Fri Oct 18, 2019 10:28 pm

Sounds a bit like The Hobbit's original screens! Could be efficient but not sure about the detail...
You'd maybe end up programming it as a list of numbers that are passed to the ROM routines for drawing lines, and then a fast fill. Almost like writing it in BASIC with PLOT and DRAW.

Or you could define some simple UDGs; e.g. horizontal, vertical and diagonal lines, corner triangles, 1x1 and 2x2 quarter curves, then draw the screen with just characters and attributes. That'd be 1.5K a screen. Then run a compressor on that stream of bytes.

Actually a 3x3 quarter circle is quite efficient to do with characters if you hit the corner of the 2x2 inner square with the curve. Then you only need 4 UDGs to describe it. The rest of the characters are all solid or empty. Good for wheels on a bus of lies!
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