Re: MiniDict3 Screen Compressor for Spectrum
Posted: Fri Oct 18, 2019 11:28 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!
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!