From 2a8c290e0de5e657f22a0c13817df65688b01345 Mon Sep 17 00:00:00 2001
From: jonkraber <jonkraber@trac.wxwidgets.org>
Date: Sun, 24 Dec 2017 15:37:10 +0100
Subject: [PATCH 1/3] Restore previous clipping box in wxDCClipper

Remember the clipping box of the previously active clipping region in
wxDCClipper ctor and restore it in its dtor.

See #13834.
---
 include/wx/dc.h | 22 ++++++++++++++++++----
 1 file changed, 18 insertions(+), 4 deletions(-)

diff --git a/include/wx/dc.h b/include/wx/dc.h
index 7cfe17fb14..dadbe793a3 100644
--- a/include/wx/dc.h
+++ b/include/wx/dc.h
@@ -1436,16 +1436,30 @@ class WXDLLIMPEXP_CORE wxDCClipper
 {
 public:
     wxDCClipper(wxDC& dc, const wxRegion& r) : m_dc(dc)
-        { dc.SetClippingRegion(r.GetBox()); }
+    {
+        dc.GetClippingBox(m_oldClipRect);
+        dc.SetClippingRegion(r.GetBox());
+    }
     wxDCClipper(wxDC& dc, const wxRect& r) : m_dc(dc)
-        { dc.SetClippingRegion(r.x, r.y, r.width, r.height); }
+    {
+        dc.GetClippingBox(m_oldClipRect);
+        dc.SetClippingRegion(r.x, r.y, r.width, r.height);
+    }
     wxDCClipper(wxDC& dc, wxCoord x, wxCoord y, wxCoord w, wxCoord h) : m_dc(dc)
-        { dc.SetClippingRegion(x, y, w, h); }
+    {
+        dc.GetClippingBox(m_oldClipRect);
+        dc.SetClippingRegion(x, y, w, h);
+    }
 
-    ~wxDCClipper() { m_dc.DestroyClippingRegion(); }
+    ~wxDCClipper()
+    {
+        m_dc.DestroyClippingRegion();
+        m_dc.SetClippingRegion(m_oldClipRect);
+    }
 
 private:
     wxDC& m_dc;
+    wxRect m_oldClipRect;
 
     wxDECLARE_NO_COPY_CLASS(wxDCClipper);
 };

From ba719c576ec72d42186309131d30c111309a2ce9 Mon Sep 17 00:00:00 2001
From: John Roberts <johnr@iinet.net.au>
Date: Sun, 24 Dec 2017 15:39:40 +0100
Subject: [PATCH 2/3] Document the new wxDCClipper behaviour after last commit
 change

wxDCClipper does restore the (bounding box of the) previously active
clipping region now.

See #13834.
---
 interface/wx/dc.h | 9 ++++-----
 1 file changed, 4 insertions(+), 5 deletions(-)

diff --git a/interface/wx/dc.h b/interface/wx/dc.h
index 67ce583325..79490c9c9a 100644
--- a/interface/wx/dc.h
+++ b/interface/wx/dc.h
@@ -1669,11 +1669,10 @@ public:
     }
     @endcode
 
-    @note Unlike other similar classes such as wxDCFontChanger, wxDCClipper
-        currently doesn't restore the previously active clipping region when it
-        is destroyed but simply resets clipping on the associated wxDC. This
-        may be changed in the future wxWidgets versions but has to be taken
-        into account explicitly in the current one.
+    @note Since 3.1.1 wxDCClipper restores the previously active clipping
+        region when it is destroyed. Previously it reset clipping on the
+        associated wxDC and this has to be taken into account explicitly in
+        previous wxWidgets versions.
 
     @library{wxcore}
     @category{gdi}

From 7f52ff751f377ab616550fdf9dbbfeff2f808332 Mon Sep 17 00:00:00 2001
From: jonkraber <jonkraber@trac.wxwidgets.org>
Date: Sun, 24 Dec 2017 15:43:20 +0100
Subject: [PATCH 3/3] Fix clipping of cell contents in wxGrid

Use wxDCClipper, now that it doesn't lose the previously set clipping
region any more, in wxGridCellStringRenderer::Draw() to ensure that we
don't overflow the area allocated for the cell.

Closes #17872.
---
 src/generic/grid.cpp     | 5 ++++-
 src/generic/gridctrl.cpp | 4 +---
 2 files changed, 5 insertions(+), 4 deletions(-)

diff --git a/src/generic/grid.cpp b/src/generic/grid.cpp
index 64b2113ebf..37041f5d1d 100644
--- a/src/generic/grid.cpp
+++ b/src/generic/grid.cpp
@@ -1871,7 +1871,10 @@ void wxGrid::Render( wxDC& dc,
     dc.DrawRectangle( pointOffSet, sizeCells );
 
     // draw cells
-    DrawGridCellArea( dc, renderCells );
+    {
+        wxDCClipper clipper( dc, wxRect(pointOffSet, sizeCells) );
+        DrawGridCellArea( dc, renderCells );
+    }
 
     // draw grid lines
     if ( style & wxGRID_DRAW_CELL_LINES )
diff --git a/src/generic/gridctrl.cpp b/src/generic/gridctrl.cpp
index 36ff071777..ecd8ac5d13 100644
--- a/src/generic/gridctrl.cpp
+++ b/src/generic/gridctrl.cpp
@@ -630,8 +630,7 @@ void wxGridCellStringRenderer::Draw(wxGrid& grid,
             for (int i = col + cell_cols; i <= col_end; i++)
             {
                 clip.width = grid.GetColSize(i) - 1;
-                dc.DestroyClippingRegion();
-                dc.SetClippingRegion(clip);
+                wxDCClipper clipper(dc, clip);
 
                 SetTextColoursAndFont(grid, attr, dc,
                         grid.IsInSelection(row,i));
@@ -644,7 +643,6 @@ void wxGridCellStringRenderer::Draw(wxGrid& grid,
             rect = rectCell;
             rect.Inflate(-1);
             rect.width++;
-            dc.DestroyClippingRegion();
         }
     }