function OnAbout(event)
   ctrl = event:GetTextCtrl()
   ctrl:AppendText("Designed for use with Mach3 and MachMotion's X15-250-PK(xxxx) controls, with the 301d Torch Height Controller.\n")
   ctrl:AppendText("Last Updated on 09-06-14\n")
   ctrl:AppendText("\n")
   ctrl:AppendText("Post Processor Comments:\n")
   ctrl:AppendText("Modal G-codes and coordinates\n")
   ctrl:AppendText("Comments enclosed with ( and )\n")
   ctrl:AppendText("M418 Is the initialization macro to ensure everything is setup correctly\n")
   ctrl:AppendText("M419 Needs to be added into Mach3's initialization string\n")
   ctrl:AppendText("M460 Auto torch reference, torch on, pierce delay. Cut height configurable on the control, along with reference feedrate\n")
   ctrl:AppendText("M422 Controls all the positive Z moves\n")
   ctrl:AppendText("M430 Controls the drill cycle\n")
   ctrl:AppendText("M431 Sends the drill bit size needed to the control\n")
   ctrl:AppendText("M6 Toolchange: Tools 1-99 are plasma, 100-249 are drill bits, and 250-255 custom/marker-tools.\n")
   ctrl:AppendText("Post variables:\n")
   ctrl:AppendText("Ref distance - set the distance between each reference\n")
end


--The cutter will slow down for corners and turn off THC below this radius
SlowRadius = 15.8750

--Minimum slow down speed.
--This is a scale factor. For instance 0.5 = 50% of the current feed rate
SlowPercent = 0.4   


-- This breaks the arc's up in 90 degree segments
post.SetOptions(post.ARC_SEGMENTS)

post.DefineVariable("SlowRadius",sc.unitLINEAR,-1e17,1e17)
post.DefineVariable("SlowPercent",sc.unitPERCENT,-1e17,1e17)


function OnInit()

   post.SetCommentChars ("()", "[]")  --make sure ( and ) characters do not appear in system text
   post.Text (" (Filename: ", fileName, ")\n")
   post.Text (" (Post processor: ", postName, ")\n")
   post.Text (" (Date: ", date, ")\n")
   if(scale == metric) then
      post.Text (" G21 (Units: Metric)\n") --metric mode
   else
      post.Text (" G20 (Units: Inches)\n") --inch mode
   end
   post.Text (" G90 G90.1 G40 S500 M418\n")

   switchoffset = 0
   minArcSize = 0.05 --arcs smaller than this are converted to moves
end

function OnNewLine()
   post.Text ("N")
   post.Number (lineNumber, "0000")
   lineNumber = lineNumber + 10
end

function OnFinish()
   --post.Text (" M05 (Torch Off)\n")
   post.Text (" M30 (Program Rewind)\n")
end

function OnRapid()
   if endX > 10000 or endY > 10000 then return end
   if(math.hypot(endX-currentX , endY-currentY) < 0.001) then return end
--   post.Text (" M422 (Torch Up)")
   post.Eol()
   post.Text (" G00")
   post.NonModalNumber (" X", endX * scale, "0.0000")
   post.NonModalNumber (" Y", endY * scale, "0.0000")
   post.Eol()
end

function OnMove()
   if endX > 10000 or endY > 10000 then return end
   if(math.hypot(endX-currentX , endY-currentY) < 0.001) then return end
   post.Text (" G01")
   post.NonModalNumber (" X", endX * scale, "0.0000")
   post.NonModalNumber (" Y", endY * scale, "0.0000")
   post.NonModalNumber (" F", feedRate * scale, "0.###")
   post.Eol()
end

--function OnArc()
--    post.ArcAsMoves(0.01)
--end

function OnArc()
local radius = math.hypot(currentX - arcCentreX, currentY - arcCentreY)

   if (radius < SlowRadius) and (math.abs(arcAngle) > 0.5) then
      feed = (radius / SlowRadius)
      if(feed < SlowPercent) then
         feed = SlowPercent
      end
      feed = feed * feedRate
--      ThcOff()
   else
      feed = feedRate
--      ThcOn()
   end
 
   if(arcAngle <0) then
      post.Text(" G03")
   else
      post.Text(" G02")
   end
   post.NonModalNumber (" X", endX * scale, "0.0000")
   post.NonModalNumber (" Y", endY * scale, "0.0000")
   post.Text (" I")
   post.Number ((arcCentreX) * scale, "0.0000")
   --post.Number ((arcCentreX - currentX) * scale, "0.0000") This is for incremental IJ mode
   post.Text (" J")
   post.Number ((arcCentreY) * scale, "0.0000")
   --post.Number ((arcCentreY - currentY) * scale, "0.0000") This is for incremental IJ mode
   post.NonModalNumber (" F", feed * scale, "0.0###")
   post.Eol()
end

function OnPenDown()
   if (toolClass == "MarkerTool") then 
      post.Eol()
      post.Text (" M435 ")
      post.Text (" (Plate Marker Down)")
      post.Eol()
      post.CancelModalNumbers()
	    if (pierceDelay > 0) then
			post.Text (" G04 P")
			post.Number (pierceDelay,"0.###")
			post.Text (" (Delay)")
			post.Eol()
		end
   end
   
   if(toolClass == "FlameTool") then
      post.Eol()
      post.Text(" M460 (PreHeat, Cut On, Pierce Delay)\n")
      post.CancelModalNumbers()   
   end
   
   if (toolClass == "PlasmaTool") then 
      post.Eol()
      post.Text(" M460 (Torch Reference, Torch On, Pierce Delay)\n")
      post.Eol()
      post.CancelModalNumbers()
   end
   
end

function OnPenUp()
   if (toolClass == "MarkerTool") then 
      post.Eol()
      post.Text (" M436 ")
      post.Text (" (Plate Marker Up)")
      post.Eol()
   elseif(toolClass == "FlameTool") then
         post.Text (" M461 (Oxy Fuel Off, Up)\n")
   else     
         post.Text (" M461 (Torch Off, Torch Up)\n")
   end

   if (endDelay > 0) then
      post.Text (" G04 P")
      post.Number (endDelay,"0.###")
      post.Text (" (Delay)")
      post.Eol()
   end
end

function OnNewOperation()
   post.Text (" (Process: ", operationName, ")\n")
end

function OnComment()
  post.Text(" (",commentText,")\n")
end

function OnToolChange()
   
   if toolClass == "DrillTool" then 
      post.Text(" M431 P ")
      post.Number(toolDia * scale, "0.0###")
      post.Text(" Q ")
      post.Number(spindleSpeed, "0.0###")
      post.Text(" R ")
      post.Number(plungeRate, "0.0###")
      post.Eol()
   end 
   
   if toolClass == "MarkerTool" then 
   --post.Text("Arc voltage is PlateMarker") 
   end 

   post.Text (" M06 T")
   post.Number (tool, "0")
   post.Text ("  (", toolName, ")\n")
   if (feedRate <= 0) then
      post.Warning("WARNING: Feed rate is zero")
   end
end

function OnNewPart()
   post.Text(" (Part: ",partName,")\n");
end

function OnDrill()
   OnRapid()
   post.Eol()
   post.Text (" M430 ")
   post.Text (" (Drill Cycle)")
   post.Eol()
end