1 files changed, 127 insertions, 0 deletions
diff --git a/wx+/dc.h b/wx+/dc.h
new file mode 100644
index 00000000..d0f5c805
--- /dev/null
+++ b/wx+/dc.h
@@ -0,0 +1,127 @@
+// **************************************************************************
+// * This file is part of the FreeFileSync project. It is distributed under *
+// * GNU General Public License: http://www.gnu.org/licenses/gpl.html       *
+// * Copyright (C) Zenju (zenju AT gmx DOT de) - All Rights Reserved        *
+// **************************************************************************
+
+#ifndef DC_3813704987123956832143243214
+#define DC_3813704987123956832143243214
+
+#include <wx/dcbuffer.h> //for macro: wxALWAYS_NATIVE_DOUBLE_BUFFER
+
+namespace zen
+{
+/*
+1. wxDCClipper does *not* stack: another fix for yet another poor wxWidgets implementation
+
+class RecursiveDcClipper
+{
+    RecursiveDcClipper(wxDC& dc, const wxRect& r) : dc_(dc)
+};
+
+------------------------------------------------------------------------------------------------
+
+2. wxAutoBufferedPaintDC skips one pixel on left side when RTL layout is active: a fix for a poor wxWidgets implementation
+class BufferedPaintDC
+{
+    BufferedPaintDC(wxWindow& wnd, std::unique_ptr<wxBitmap>& buffer);
+};
+*/
+
+
+
+
+
+
+
+
+
+
+
+//---------------------- implementation ------------------------
+class RecursiveDcClipper
+{
+public:
+    RecursiveDcClipper(wxDC& dc, const wxRect& r) : dc_(dc)
+    {
+        auto it = refDcToAreaMap().find(&dc);
+        if (it != refDcToAreaMap().end())
+        {
+            oldRect.reset(new wxRect(it->second));
+
+            wxRect tmp = r;
+            tmp.Intersect(*oldRect);    //better safe than sorry
+            dc_.SetClippingRegion(tmp); //
+            it->second = tmp;
+        }
+        else
+        {
+            dc_.SetClippingRegion(r);
+            refDcToAreaMap().insert(std::make_pair(&dc_, r));
+        }
+    }
+
+    ~RecursiveDcClipper()
+    {
+        dc_.DestroyClippingRegion();
+        if (oldRect.get() != nullptr)
+        {
+            dc_.SetClippingRegion(*oldRect);
+            refDcToAreaMap()[&dc_] = *oldRect;
+        }
+        else
+            refDcToAreaMap().erase(&dc_);
+    }
+
+private:
+	//associate "active" clipping area with each DC
+	static hash_map<wxDC*, wxRect>& refDcToAreaMap() { static hash_map<wxDC*, wxRect> clippingAreas; return clippingAreas; }
+
+    std::unique_ptr<wxRect> oldRect;
+    wxDC& dc_;
+};
+
+
+#ifndef wxALWAYS_NATIVE_DOUBLE_BUFFER
+#error we need this one!
+#endif
+
+#if wxALWAYS_NATIVE_DOUBLE_BUFFER
+struct BufferedPaintDC : public wxPaintDC { BufferedPaintDC(wxWindow& wnd, std::unique_ptr<wxBitmap>& buffer) : wxPaintDC(&wnd) {} };
+
+#else
+class BufferedPaintDC : public wxMemoryDC
+{
+public:
+    BufferedPaintDC(wxWindow& wnd, std::unique_ptr<wxBitmap>& buffer) : buffer_(buffer), paintDc(&wnd)
+    {
+        const wxSize clientSize = wnd.GetClientSize();
+        if (!buffer_ || clientSize != wxSize(buffer->GetWidth(), buffer->GetHeight()))
+            buffer.reset(new wxBitmap(clientSize.GetWidth(), clientSize.GetHeight()));
+
+        SelectObject(*buffer);
+
+        if (paintDc.IsOk() && paintDc.GetLayoutDirection() == wxLayout_RightToLeft)
+            SetLayoutDirection(wxLayout_RightToLeft);
+    }
+
+    ~BufferedPaintDC()
+    {
+        if (GetLayoutDirection() == wxLayout_RightToLeft)
+        {
+            paintDc.SetLayoutDirection(wxLayout_LeftToRight); //workaround bug in wxDC::Blit()
+            SetLayoutDirection(wxLayout_LeftToRight);         //
+        }
+
+        const wxPoint origin = GetDeviceOrigin();
+        paintDc.Blit(0, 0, buffer_->GetWidth(), buffer_->GetHeight(), this, -origin.x, -origin.y);
+    }
+
+private:
+    std::unique_ptr<wxBitmap>& buffer_;
+    wxPaintDC paintDc;
+};
+#endif
+}
+
+#endif //DC_3813704987123956832143243214