class BBS::Petscii::Encoder

Turns what a BBS writes into PETSCII. It keeps the cursor’s column, so a line of exactly 40 characters, which the C64 wraps by itself, is not followed by an empty one, and it keeps the state of an escape sequence cut in two by separate writes.

Constants

CONTROL_ACTIONS: What a control character does, by code: the method that handles it.
PLAIN_PEN: The pen after a reset: no bold, no dim, the default colour.

Public Class Methods

new ()

Source

# File lib/bbs/petscii/encoder.rb, line 20
def initialize
  @col     = 0
  @wrapped = false
  @lone_cr = false
  @rvs     = false
  @pen     = PLAIN_PEN
  @color   = nil
  @esc     = nil
end

Creates an encoder at column 0 with no colour, reverse video or escape sequence pending.

Public Instance Methods

encode (data)

Source

# File lib/bbs/petscii/encoder.rb, line 37
def encode(data)
  text = data.to_s.dup.force_encoding(Encoding::UTF_8)
  text = text.scrub('?') unless text.valid_encoding?
  out  = +''.b
  text.each_char { |ch| feed(ch, out) }
  out
end

Returns the PETSCII bytes (a binary String) for data, UTF-8 text with ANSI escape sequences. Letters swap case, box drawing and other symbols become the nearest PETSCII glyph (GLYPHS, accents dropped, ? when there is none), SGR colours and reverse video become colour and RVS codes, cursor moves become cursor control codes, and \e[2J clears the screen. Other sequences are dropped. The encoder’s column and colour state carry over to the next call.