Class: Przn::Renderer

Inherits:
Object
  • Object
show all
Defined in:
lib/przn/renderer.rb

Constant Summary collapse

ANSI = 
{
  bold:          "\e[1m",
  italic:        "\e[3m",
  reverse:       "\e[7m",
  strikethrough: "\e[9m",
  dim:           "\e[2m",
  cyan:          "\e[36m",
  gray_bg:       "\e[48;5;236m",
  reset:         "\e[0m",
}.freeze
DEFAULT_SCALE = 
2

Instance Method Summary collapse

Constructor Details

#initialize(terminal, base_dir: '.', theme: nil) ⇒ Renderer

Returns a new instance of Renderer.



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# File 'lib/przn/renderer.rb', line 18

def initialize(terminal, base_dir: '.', theme: nil)
  @terminal = terminal
  @base_dir = base_dir
  @theme = theme || Theme.default
  @image_cache = {}
  @kitty_uploads = {}
  @mutex = Mutex.new
end

Instance Method Details

#preload(slide) ⇒ Object

Warm caches for a slide we expect to navigate to soon. Uploads any PNG images on the Kitty Graphics Protocol so the next render only needs a placement command. Safe to call from a background thread; serialized against ‘render` via the renderer’s mutex so terminal writes don’t interleave.



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# File 'lib/przn/renderer.rb', line 65

def preload(slide)
  return unless ImageUtil.kitty_terminal?

  @mutex.synchronize do
    slide.blocks.each do |block|
      next unless block[:type] == :image
      path = resolve_image_path(block[:path])
      next unless File.exist?(path) && ImageUtil.png?(path)
      ensure_kitty_uploaded(path)
    end
    @terminal.flush
  end
end

#render(slide, current:, total:) ⇒ Object 



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# File 'lib/przn/renderer.rb', line 27

def render(slide, current:, total:)
  @mutex.synchronize do
    @terminal.clear
    apply_slide_background(slide)
    w = @terminal.width
    h = @terminal.height

    row = if current == 0
      content_height = calculate_height(slide.blocks, w)
      usable_height = h - 1
      [(usable_height - content_height) / 2 + 1, 1].max
    else
      2
    end

    pending_align = nil
    slide.blocks.each do |block|
      if block[:type] == :align
        pending_align = block[:align]
      else
        row = render_block(block, w, row, align: pending_align)
        pending_align = nil
      end
    end

    status = " #{current + 1} / #{total} "
    @terminal.move_to(h, w - status.size)
    @terminal.write "#{ANSI[:dim]}#{status}#{ANSI[:reset]}"

    @terminal.flush
  end
end