braille code plane support

Views/Grid.xaml.fs

@@ -190,7 +190,7 @@ type Grid() as this =
  // Therefore, we have to break them into single glyphs
  // to prevent overflow into later cells.
  let hlidchange = prev_hlid <> current.hlid
- if hlidchange || mywc <> wc || bold || sym <> mysym then
+ if hlidchange || mywc <> wc || bold || sym <> mysym || mywc = CharType.Braille then
  // If the span split is caused by symbols, we put [x+1]
  // into the current span because nr_symbols has latched one rune.
  let prev_span = if mysym && not sym && mywc = wc && not bold && not hlidchange 

ui.fs

@@ -142,11 +142,19 @@ let DefaultFontEmoji =
  elif RuntimeInformation.IsOSPlatform(OSPlatform.OSX) then "Apple Color Emoji"
  else "Noto Color Emoji"
 
+let DefaultFontBraille =
+ if RuntimeInformation.IsOSPlatform(OSPlatform.Windows) then "Segoe UI Symbol"
+ elif RuntimeInformation.IsOSPlatform(OSPlatform.Linux) then "Monospace" // ?
+ elif RuntimeInformation.IsOSPlatform(OSPlatform.OSX) then "Menlo" // ?
+ else "Monospace"
+
+
 let private nerd_typeface = 
  let name = if RuntimeInformation.IsOSPlatform(OSPlatform.OSX) then "Iosevka NF"
  else "Iosevka"
  Typeface($"resm:fvim.Fonts.nerd.ttf?assembly=FVim#{name}")
 let private emoji_typeface = Typeface(DefaultFontEmoji)
+let private braille_typeface = Typeface(DefaultFontBraille)
 let private fontcache = System.Collections.Generic.Dictionary<string*bool*bool, Typeface>()
 
 let InvalidateFontCache () =
@@ -182,6 +190,7 @@ let GetTypeface(txt, italic, bold, font, wfont) =
  | CharType.Powerline
  | CharType.Nerd when not states.font_nonerd -> nerd_typeface
  | CharType.Emoji -> emoji_typeface
+ | CharType.Braille -> braille_typeface
  | _ -> _get font
 
 let MeasureText (rune: Rune, font: string, wfont: string, fontSize: float, scaling: float) =