From 6cea553fa3dfcd189033fec8fb9bdd3d2dbc7677 Mon Sep 17 00:00:00 2001
From: Vadim Zeitlin <vadim@wxwidgets.org>
Date: Sun, 14 Sep 2014 00:59:56 +0000
Subject: [PATCH] Avoid creating wxGraphicsContext in the drawing sample
 unnecessarily.

This is not only wasteful, but creating a Direct2D surface associated with a
wxDC makes it impossible to paint on the DC using GDI functions, so this
completely broke the initial display in the sample.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@77690 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775
---
 samples/drawing/drawing.cpp | 39 ++++++++++++++++++++-----------------
 1 file changed, 21 insertions(+), 18 deletions(-)

diff --git a/samples/drawing/drawing.cpp b/samples/drawing/drawing.cpp
index e4f8bebf32..c423d21121 100644
--- a/samples/drawing/drawing.cpp
+++ b/samples/drawing/drawing.cpp
@@ -1550,28 +1550,31 @@ void MyCanvas::Draw(wxDC& pdc)
 #endif
         ;
 
-    wxGraphicsContext* context;
-    if ( wxPaintDC *paintdc = wxDynamicCast(&pdc, wxPaintDC) )
+    if ( m_useContext )
     {
-        context = renderer->CreateContext(*paintdc);
-    }
-    else if ( wxMemoryDC *memdc = wxDynamicCast(&pdc, wxMemoryDC) )
-    {
-        context = renderer->CreateContext(*memdc);
-    }
+        wxGraphicsContext* context;
+        if ( wxPaintDC *paintdc = wxDynamicCast(&pdc, wxPaintDC) )
+        {
+            context = renderer->CreateContext(*paintdc);
+        }
+        else if ( wxMemoryDC *memdc = wxDynamicCast(&pdc, wxMemoryDC) )
+        {
+            context = renderer->CreateContext(*memdc);
+        }
 #if wxUSE_METAFILE && defined(wxMETAFILE_IS_ENH)
-    else if ( wxMetafileDC *metadc = wxDynamicCast(&pdc, wxMetafileDC) )
-    {
-        context = renderer->CreateContext(*metadc);
-    }
+        else if ( wxMetafileDC *metadc = wxDynamicCast(&pdc, wxMetafileDC) )
+        {
+            context = renderer->CreateContext(*metadc);
+        }
 #endif
-    else
-    {
-        wxFAIL_MSG( "Unknown wxDC kind" );
-        return;
-    }
+        else
+        {
+            wxFAIL_MSG( "Unknown wxDC kind" );
+            return;
+        }
 
-    gdc.SetGraphicsContext(context);
+        gdc.SetGraphicsContext(context);
+    }
 
     wxDC &dc = m_useContext ? (wxDC&) gdc : (wxDC&) pdc ;
 #else