X-Git-Url: https://git.saurik.com/wxWidgets.git/blobdiff_plain/19c9f36f130144ac4ba03aa8daf5d35043c0b766..fd2ce1d1c18045f2ecce14d888473e8131c0d23c:/src/common/dcbufcmn.cpp?ds=sidebyside

diff --git a/src/common/dcbufcmn.cpp b/src/common/dcbufcmn.cpp
index d76a8a545e..ed6bb0e7bb 100644
--- a/src/common/dcbufcmn.cpp
+++ b/src/common/dcbufcmn.cpp
@@ -24,17 +24,64 @@
     #pragma hdrstop
 #endif
 
+#include "wx/dcbuffer.h"
+
 #ifndef WX_PRECOMP
+    #include "wx/module.h"
 #endif
 
-#include "wx/dcbuffer.h"
+// ============================================================================
+// implementation
+// ============================================================================
+
+// ----------------------------------------------------------------------------
+// wxSharedDCBufferManager: helper class maintaining backing store bitmap
+// ----------------------------------------------------------------------------
 
+class wxSharedDCBufferManager : public wxModule
+{
+public:
+    wxSharedDCBufferManager() { }
+
+    virtual bool OnInit() { return true; }
+    virtual void OnExit() { wxDELETE(ms_buffer); }
+
+    static wxBitmap* GetBuffer(int w, int h)
+    {
+        if ( !ms_buffer ||
+                w > ms_buffer->GetWidth() ||
+                    h > ms_buffer->GetHeight() )
+        {
+            delete ms_buffer;
+            ms_buffer = new wxBitmap(w, h);
+        }
+        return ms_buffer;
+    }
+
+private:
+    static wxBitmap *ms_buffer;
+
+    DECLARE_DYNAMIC_CLASS(wxSharedDCBufferManager)
+};
+
+wxBitmap* wxSharedDCBufferManager::ms_buffer = NULL;
+
+IMPLEMENT_DYNAMIC_CLASS(wxSharedDCBufferManager, wxModule)
 
 // ============================================================================
-// implementation
+// wxBufferedDC
 // ============================================================================
 
-// This file is intentionally empty.  It has not been removed in case another
-// wxBufferedDC reimplementation is attempted in the near future.  If not then
-// this file can be removed and the bakefiles updated.
+void wxBufferedDC::UseBuffer(wxCoord w, wxCoord h)
+{
+    if ( !m_buffer || !m_buffer->IsOk() )
+    {
+        if ( w == -1 || h == -1 )
+            m_dc->GetSize(&w, &h);
+
+        m_buffer = wxSharedDCBufferManager::GetBuffer(w, h);
+    }
+
+    SelectObject(*m_buffer);
+}