InputRoll - in horizontal orientation, account for the draw area being shorter than the height of the columns

BizHawk.Client.EmuHawk/CustomControls/InputRoll/InputRoll.Drawing.cs

@@ -21,11 +21,15 @@ namespace BizHawk.Client.EmuHawk
 				// Lag frame calculations
 				SetLagFramesArray();
 
+				CalculateHorizontalColumnPositions(VisibleColumns.ToList());
+
 				List<RollColumn> visibleColumns;
 
 				if (HorizontalOrientation)
 				{
-					visibleColumns = VisibleColumns.ToList(); // TODO
+					visibleColumns = VisibleColumns
+						.Take(_horizontalColumnTops.Count(c => c < e.ClipRectangle.Height))
+						.ToList();
 				}
 				else
 				{
@@ -34,7 +38,7 @@ namespace BizHawk.Client.EmuHawk
 						.Where(c => c.Left - _hBar.Value < e.ClipRectangle.Width)
 						.ToList();
 				}
-				
+
 				var firstVisibleRow = Math.Max(FirstVisibleRow, 0);
 				var visibleRows = HorizontalOrientation
 					? e.ClipRectangle.Width / CellWidth
@@ -42,8 +46,6 @@ namespace BizHawk.Client.EmuHawk
 
 				var lastVisibleRow = firstVisibleRow + visibleRows;
 
-				CalculateHorizontalColumnPositions(visibleColumns);
-
 				var needsColumnRedraw = HorizontalOrientation || e.ClipRectangle.Y < ColumnHeight;
 				if (visibleColumns.Any() && needsColumnRedraw)
 				{

BizHawk.Client.EmuHawk/CustomControls/InputRoll/InputRoll.cs

@@ -285,6 +285,8 @@ namespace BizHawk.Client.EmuHawk
 				int h = VisibleColumns.Any()
 					? GetHColBottom(VisibleColumns.Count() - 1)
 					: 0;
+				h = Math.Min(h, _drawHeight);
+
 				Invalidate(new Rectangle(x, y, w, h));
 			}
 			else