debug2.lua

module(...,package.seeall)

local number_sp_in_a_pdf_point = 65782

function math.round(num, idp)
  if idp and idp>0 then
    local mult = 10^idp
    return math.floor(num * mult + 0.5) / mult
  end
  return math.floor(num + 0.5)
end

function show_page_elements(parent)
  local head = parent.list
  while head do
    if head.id == 0 or head.id == 1 then -- hbox / vbox

      local rule_width = 1
      local wd = math.round(head.width                  / number_sp_in_a_pdf_point - rule_width     ,2)
      local ht = math.round((head.height + head.depth)  / number_sp_in_a_pdf_point - rule_width     ,2)
      local dp = math.round(head.depth                  / number_sp_in_a_pdf_point - rule_width / 2 ,2)

      -- recurse into the contents of the box
      show_page_elements(head)
      local rectangle = node.new("whatsit","pdf_literal")
      if head.id == 0 then -- hbox
        rectangle.data = string.format("q 0.5 G %g w %g %g %g %g re s Q", rule_width, -rule_width / 2, -dp, wd, ht)
      else
        rectangle.data = string.format("q 0.1 G %g w %g %g %g %g re s Q", rule_width, -rule_width / 2, 0, wd, -ht)
      end
      head.list = node.insert_before(head.list,head.list,rectangle)


    elseif head.id == 2 then -- rule
      local show_rule = node.new("whatsit","pdf_literal")
      if head.width == -1073741824 or head.height == -1073741824 or head.depth == -1073741824 then
        -- ignore for now -- these rules are stretchable
      else
        local dp = math.round( head.depth / number_sp_in_a_pdf_point  ,2)
        local ht = math.round( head.height / number_sp_in_a_pdf_point ,2)
        show_rule.data =  string.format("q 1 0 0 RG 1 0 0 rg 0.4 w 0 %g m 0 %g l S Q",-dp,ht)
      end
      parent.list = node.insert_before(parent.list,head,show_rule)


    elseif head.id == 7 then -- disc
      local hyphen_marker = node.new("whatsit","pdf_literal")
      hyphen_marker.data = "q 0 0 1 RG 0.3 w 0 -1 m 0 0 l S Q"
      parent.list = node.insert_before(parent.list,head,hyphen_marker)


  elseif head.id == 10 then -- glue
      local wd = head.spec.width
      local color = "0.5 G"
      if parent.glue_sign == 1 and parent.glue_order == head.spec.stretch_order then
        wd = wd + parent.glue_set * head.spec.stretch
        color = "0 0 1 RG"
      elseif parent.glue_sign == 2 and parent.glue_order == head.spec.shrink_order then
        wd = wd - parent.glue_set * head.spec.shrink
        color = "1 0 1 RG"
      end
      local pdfstring = node.new("whatsit","pdf_literal")
      local wd_bp = math.round(wd / number_sp_in_a_pdf_point,2)
      if parent.id == 0 then --hlist
        pdfstring.data = string.format("q %s [2 2] 0 d  1.8 w 0 0  m %g 0 l s Q",color,wd_bp)
      else -- vlist
        pdfstring.data = string.format("q 0.1 G 0.1 w -0.5 0 m 0.5 0 l -0.5 %g m 0.5 %g l s [0.2] 0 d  0.5 w 0.25 0  m 0.25 %g l s Q",-wd_bp,-wd_bp,-wd_bp)
      end
      parent.list = node.insert_before(parent.list,head,pdfstring)


    elseif head.id == 11 then -- kern
      local rectangle = node.new("whatsit","pdf_literal")
      local color = "1 1 0 rg"
      if head.kern < 0 then color = "1 0 0 rg" end
      local k = math.round(head.kern / number_sp_in_a_pdf_point,2)
      if parent.id == 0 then --hlist
        rectangle.data = string.format("q %s 0 w 0 0  %g 1 re B Q",color, k )
      else
        rectangle.data = string.format("q %s 0 w 0 0  1 %g re B Q",color, -k )
      end
      parent.list = node.insert_before(parent.list,head,rectangle)

    elseif head.id == 12 then -- penalty
      local color = "1 g"
      local rectangle = node.new("whatsit","pdf_literal")
      if head.penalty < 10000 then
        color = string.format("%d g", 1 - head.penalty / 10000)
      end
      rectangle.data = string.format("q %s 0 w 0 0 10 10 re B Q",color)
      parent.list = node.insert_before(parent.list,head,rectangle)

    elseif head.id == 37 then -- glyph
      local rule_width = 0.8
      local wd = math.round(head.width                  / number_sp_in_a_pdf_point - rule_width     ,2)
      local ht = math.round((head.height + head.depth)  / number_sp_in_a_pdf_point - rule_width     ,2)
      local dp = math.round(head.depth                  / number_sp_in_a_pdf_point - rule_width / 2 ,2)

      local rectangle = node.new("whatsit","pdf_literal")
      rectangle.data = string.format("q 1 0 0 RG %g w %g %g %g %g re s Q", rule_width, -rule_width / 2, -dp, wd, ht) ..
		string.format(" q 0 0 1 RG %g w %g %g m %g %g l s Q", rule_width, -rule_width/2, 0, wd, 0)
      parent.list = node.insert_before(parent.list,head,rectangle)

    else
      texio.write("### node " .. head.id .. "\n")
    end
    head = head.next
  end
  return true
end