Use NLuaTableHelper for more conversion to/from LuaTable

also fix indexing that I broke in c8e10120d

src/BizHawk.Client.Common/lua/CommonLibs/GuiLuaLibrary.cs

@@ -63,9 +63,10 @@ namespace BizHawk.Client.Common
 			{
 				var pointsArr = new Point[4];
 				var i = 0;
-				foreach (var point in _th.EnumerateValues<LuaTable>(points))
+				foreach (var point in _th.EnumerateValues<LuaTable>(points)
+					.Select(table => _th.EnumerateValues<double>(table).ToList()))
 				{
-					pointsArr[i] = new Point(LuaInt(point[1]), LuaInt(point[2]));
+					pointsArr[i] = new Point(LuaInt(point[0]), LuaInt(point[1]));
 					i++;
 					if (i >= 4)
 					{
@@ -124,14 +125,15 @@ namespace BizHawk.Client.Common
 		[LuaMethod("drawPolygon", "Draws a polygon using the table of coordinates specified in points. This should be a table of tables(each of size 2). If x or y is passed, the polygon will be translated by the passed coordinate pair. Line is the color of the polygon. Background is the optional fill color")]
 		public void DrawPolygon(LuaTable points, int? offsetX = null, int? offsetY = null, Color? line = null, Color? background = null)
 		{
-			var pointsList = _th.EnumerateValues<LuaTable>(points).ToList();
+			var pointsList = _th.EnumerateValues<LuaTable>(points)
+				.Select(table => _th.EnumerateValues<double>(table).ToList()).ToList();
 			try
 			{
 				var pointsArr = new Point[pointsList.Count];
 				var i = 0;
 				foreach (var point in pointsList)
 				{
-					pointsArr[i] = new Point(LuaInt(point[1]) + (offsetX ?? 0), LuaInt(point[2]) + (offsetY ?? 0));
+					pointsArr[i] = new Point(LuaInt(point[0]) + (offsetX ?? 0), LuaInt(point[1]) + (offsetY ?? 0));
 					i++;
 				}
 				APIs.Gui.DrawPolygon(pointsArr, line, background);

src/BizHawk.Client.EmuHawk/tools/Lua/Libraries/FormsLuaLibrary.cs

@@ -422,7 +422,7 @@ namespace BizHawk.Client.EmuHawk
 				return 0;
 			}
 
-			var pictureBox = new LuaPictureBox();
+			var pictureBox = new LuaPictureBox { TableHelper = _th };
 			form.Controls.Add(pictureBox);
 
 			if (x.HasValue && y.HasValue)

src/BizHawk.Client.EmuHawk/tools/Lua/LuaCanvas.cs

@@ -15,10 +15,11 @@ namespace BizHawk.Client.EmuHawk
 	{
 		private readonly Action<string> LogOutputCallback;
 
-		public LuaCanvas(int width, int height, int? x, int? y, Action<string> logOutputCallback)
+		public LuaCanvas(int width, int height, int? x, int? y, NLuaTableHelper tableHelper, Action<string> logOutputCallback)
 		{
 			LogOutputCallback = logOutputCallback;
 			InitializeComponent();
+			luaPictureBox.TableHelper = tableHelper;
 			luaPictureBox.Image = Properties.Resources.LuaPictureBox;
 			luaPictureBox.Width = width;
 			luaPictureBox.Height = height;

src/BizHawk.Client.EmuHawk/tools/Lua/LuaPictureBox.cs

@@ -1,8 +1,11 @@
 using System;
 using System.Collections.Generic;
 using System.Drawing;
+using System.Linq;
 using System.Windows.Forms;
 
+using BizHawk.Client.Common;
+
 using NLua;
 
 namespace BizHawk.Client.EmuHawk
@@ -14,6 +17,8 @@ namespace BizHawk.Client.EmuHawk
 		private readonly Dictionary<Color, SolidBrush> _solidBrushes = new Dictionary<Color, SolidBrush>();
 		private readonly Dictionary<Color, Pen> _pens = new Dictionary<Color, Pen>();
 
+		internal NLuaTableHelper TableHelper { private get; set; }
+
 		private SolidBrush GetBrush(Color color)
 		{
 			if (!_solidBrushes.TryGetValue(color, out var b))
@@ -78,9 +83,10 @@ namespace BizHawk.Client.EmuHawk
 			var pointsArr = new Point[4];
 
 			var i = 0;
-			foreach (LuaTable point in points.Values)
+			foreach (var point in TableHelper.EnumerateValues<LuaTable>(points)
+				.Select(table => TableHelper.EnumerateValues<double>(table).ToList()))
 			{
-				pointsArr[i] = new Point((int)(double)(point[1]), (int)(double)(point[2]));
+				pointsArr[i] = new Point((int) point[0], (int) point[1]);
 				i++;
 				if (i >= 4)
 				{
@@ -252,11 +258,13 @@ namespace BizHawk.Client.EmuHawk
 
 		public void DrawPolygon(LuaTable points, int? x = null, int? y = null, Color? line = null, Color? background = null)
 		{
-			var pointsArr = new Point[points.Values.Count];
+			var pointsList = TableHelper.EnumerateValues<LuaTable>(points)
+				.Select(table => TableHelper.EnumerateValues<double>(table).ToList()).ToList();
+			var pointsArr = new Point[pointsList.Count];
 			var i = 0;
-			foreach (LuaTable point in points.Values)
+			foreach (var point in pointsList)
 			{
-				pointsArr[i] = new Point((int)(double)(point[1]) + x ?? 0, (int)(double)(point[2]) + y ?? 0);
+				pointsArr[i] = new Point((int) point[0] + x ?? 0, (int) point[1] + y ?? 0);
 				i++;
 			}
 

src/BizHawk.Client.EmuHawk/tools/Lua/Win32LuaLibraries.cs

@@ -78,7 +78,7 @@ namespace BizHawk.Client.EmuHawk
 					{
 						guiLib.CreateLuaCanvasCallback = (width, height, x, y) =>
 						{
-							var canvas = new LuaCanvas(width, height, x, y, LogToLuaConsole);
+							var canvas = new LuaCanvas(width, height, x, y, _th, LogToLuaConsole);
 							canvas.Show();
 							return _th.ObjectToTable(canvas);
 						};