blog/_plugins/latex.rb
2018-05-28 12:14:02 -05:00

42 lines
934 B
Ruby

require "mathematical"
$blockRgx = /((?<block>\$\$[^\$]+\$\$)|[^\$](?<inline>\$[^\$]+\$)[^\$])/
module Jekyll
class InlineLatex < Converter
safe true
priority :high
def matches(ext)
ext =~ /^\.md$/i
end
def output_ext(ext)
".md"
end
def convert(content)
# first pass
buf = StringIO.new
prev = 0
renderer = Mathematical.new({:base64 => true, :format => :svg})
content.to_enum(:scan, $blockRgx).map { Regexp.last_match }.to_enum.with_index.each do |match, i|
if match[:block] != nil
code = match[:block]
a, b = match.offset(:block)
else
code = match[:inline]
a, b = match.offset(:inline)
end
buf << content[prev..a].gsub(/^\$?\$/, "").gsub(/\$?\$$/, "")
render = renderer.render(code)
buf << "<img src='" + render[:data] + "' />"
prev = b - 1
end
buf << content[prev..content.length].gsub(/^\$?\$/, "")
return buf.string
end
end
end