Use Unicode braille characters for line drawing

[tenox7]

https://en.wikipedia.org/wiki/Braille_Patterns

check gotop
bashtop
etc

[hartwork]

See also #29 (comment)

[edgar-bonet]

Another alternative could be using the Block Elements ▁ (U+2581 – Lower one eighth block) through █ (U+2588 – Full block). Compared to Braille Patterns, these characters offer:

• better vertical resolution (8 lines per character cell instead of 4)
• worse horizontal resolution (1 per cell instead of 2)
• are easier to the eyes (continuously filled curve)

Should this be a separate feature request? Maybe it would be too much to support both?

[jwilk]

Since Unicode 13.0, there are also Teletext blocks available (3 lines × 2 columns, easy to eyes):
https://en.wikipedia.org/wiki/Symbols_for_Legacy_Computing

[tenox7]

Braille has been experiment added in head master.

[hartwork]

For anyone curious, the related commit is d480b3f and here is what…

for i in $(seq "${COLUMNS}"); do echo "${RANDOM} " ; done | ./ttyplot -b -f`

…looked like for me:

[tenox7]

is it good or bad?

we should really do a side by side comparison with ascii chars

[edgar-bonet]

Pure personal opinion: this looks just awesome! 🤩

Some random thoughts:

• I initially though the horizontal resolution would have been doubled, but it seems it is still one data point per character cell. Would it be more complex to plot two data points per cell?

• The options -f and -2 do not play nice together: when the second line overlaps a filled region, it gets very thick. I guess there is no real solution for this issue. ☹️

• The lines are 4-connected. They would be thinner if they were only 8-connected. This may look nicer, at least in block mode. Maybe they would be too thin for braille mode?