The Wikipedia page for PETSCII [1] only marks 20 characters as not having Unicode equivalents; 2px (light) and 3px (heavy) horizontal and vertical bars at various non-center positions, diagonal shading characters, and corner characters.
I’ve done some processing to the table on [1] to filter out the missing characters — their exact codepoints and descriptions can be found in [2]. These characters are highlighted in red in the attached image (green characters are also missing but are duplicates of other characters in the chart), and marked by U+FFFD � in the compact table [3]. The box-drawing characters seem to semantically represent lines (boxes) and the block elements seem to represent shapes and shades; this makes $7c, $7f, $a7, $a8, $a9, $b6, $b7, and $b8 block elements and the rest box-drawing characters. [1]: https://en.m.wikipedia.org/wiki/PETSCII [2]: https://github.com/9999years/Unicode-PETSCII/blob/master/new.txt [3]: https://github.com/9999years/Unicode-PETSCII/blob/master/graphic-table.txt [image: Inline image 1] On Wed, Apr 5, 2017 at 11:32 PM, Rebecca Bettencourt <[email protected]> wrote: > On 6 April 2017 at 09:44, James Kass <[email protected]> wrote: > >> Rebecca Bettencourt wrote, >> >> > I can put together a unified chart, with mappings to Unicode where >> > they exist. In fact I think I'll do that. :) >> >> I hope you do. That would be a good starting point. >> > > I'm working on it! > > On Wed, Apr 5, 2017 at 7:40 PM, Elias Mårtenson <[email protected]> wrote: > >> Do we also have to create an example font that includes these symbols? >> That seems to be what Michael Everson did for his chess notation proposal >> that I read recently. >> > > We do have to provide Unicode with fonts, I believe. We can use an > existing C64 font, such as Pet Me. Or, we can create a new font with > vectorized versions of the characters. > > >> Then there is the issue of what to do with the text colour and style >> selectors. PETSCII has characters that indicate a colour change as well as >> reverse video. At least the reverse video one is important, as it's being >> used to construct new characters. For example, PETSCII only has a single >> character "half block" (top part filled). The way you represent a half >> block with the bottom part filled is to use the reverse video together with >> the former. >> >> It would probably make more sense to represent the reversed symbols as >> separate code points? >> > > I would actually leave the color-change and reverse-video characters to a > higher-level protocol. > > >> >> Regards, >> Elias >> > >
