#pragma hdrstop
#endif
-#ifndef WX_PRECOMP
-#endif
-
#include "wx/dcbuffer.h"
+#ifndef WX_PRECOMP
+ #include "wx/module.h"
+#endif
// ============================================================================
// implementation
// ============================================================================
-// ============================================================================
-// wxSharedDCBufferManager
-// Helper class to free shared buffer when the app exists.
-// ============================================================================
+IMPLEMENT_DYNAMIC_CLASS(wxBufferedDC,wxMemoryDC)
+IMPLEMENT_ABSTRACT_CLASS(wxBufferedPaintDC,wxBufferedDC)
-class wxSharedDCBufferManager
+// ----------------------------------------------------------------------------
+// wxSharedDCBufferManager: helper class maintaining backing store bitmap
+// ----------------------------------------------------------------------------
+
+class wxSharedDCBufferManager : public wxModule
{
- friend class wxBufferedDC;
public:
+ wxSharedDCBufferManager() { }
- wxSharedDCBufferManager()
- {
- m_buffer = NULL;
- }
+ virtual bool OnInit() { return true; }
+ virtual void OnExit() { wxDELETE(ms_buffer); }
- ~wxSharedDCBufferManager()
+ static wxBitmap* GetBuffer(int w, int h)
{
- delete m_buffer;
- }
-
- wxBitmap* GetBuffer(wxWindow* win, const wxSize& area)
- {
- int width = area.x;
- int height = area.y;
-
- if ( width <= 0 )
- win->GetClientSize(&width, &height);
+ if ( ms_usingSharedBuffer )
+ return new wxBitmap(w, h);
- if ( !m_buffer ||
- width > m_buffer->GetWidth() ||
- height > m_buffer->GetHeight() )
+ if ( !ms_buffer ||
+ w > ms_buffer->GetWidth() ||
+ h > ms_buffer->GetHeight() )
{
- delete m_buffer;
+ delete ms_buffer;
- // Create slightly larger bitmap so we don't need to
- // be reallocating constantly when the user enlarges
- // the frame for the first time.
- m_buffer = new wxBitmap(width+20, height+20);
+ // we must always return a valid bitmap but creating a bitmap of
+ // size 0 would fail, so create a 1*1 bitmap in this case
+ if ( !w )
+ w = 1;
+ if ( !h )
+ h = 1;
+
+ ms_buffer = new wxBitmap(w, h);
}
- return m_buffer;
+ ms_usingSharedBuffer = true;
+ return ms_buffer;
+ }
+
+ static void ReleaseBuffer(wxBitmap* buffer)
+ {
+ if ( buffer == ms_buffer )
+ {
+ wxASSERT_MSG( ms_usingSharedBuffer, wxT("shared buffer already released") );
+ ms_usingSharedBuffer = false;
+ }
+ else
+ {
+ delete buffer;
+ }
}
private:
- wxBitmap* m_buffer;
+ static wxBitmap *ms_buffer;
+ static bool ms_usingSharedBuffer;
+
+ DECLARE_DYNAMIC_CLASS(wxSharedDCBufferManager)
};
-static wxSharedDCBufferManager gs_sharedDCBufferManager;
+wxBitmap* wxSharedDCBufferManager::ms_buffer = NULL;
+bool wxSharedDCBufferManager::ms_usingSharedBuffer = false;
+
+IMPLEMENT_DYNAMIC_CLASS(wxSharedDCBufferManager, wxModule)
// ============================================================================
// wxBufferedDC
// ============================================================================
-// Blits the buffer to the dc, and detaches the dc from the buffer (so it
-// can be effectively used once only).
-//
-// Usually called in the dtor or by the dtor of derived classes if the
-// BufferedDC must blit before the derived class (which may own the dc it's
-// blitting to) is destroyed.
-void wxBufferedDC::UnMask()
+void wxBufferedDC::UseBuffer(wxCoord w, wxCoord h)
{
- if ( m_buffer )
- {
- wxASSERT_MSG( m_mainDc != NULL,
- _T("No underlying DC associated with wxBufferedDC (anymore)") );
-
- wxDC* bufferDc = DetachDC();
+ wxCHECK_RET( w >= -1 && h >= -1, "Invalid buffer size" );
- wxASSERT( bufferDc->IsKindOf(CLASSINFO(wxMemoryDC)) );
+ if ( !m_buffer || !m_buffer->IsOk() )
+ {
+ if ( w == -1 || h == -1 )
+ m_dc->GetSize(&w, &h);
- wxCoord x=0, y=0;
+ m_buffer = wxSharedDCBufferManager::GetBuffer(w, h);
+ m_style |= wxBUFFER_USES_SHARED_BUFFER;
+ m_area.Set(w,h);
+ }
+ else
+ m_area = m_buffer->GetSize();
- if (m_style & wxBUFFER_CLIENT_AREA)
- bufferDc->GetDeviceOrigin(& x, & y);
+ SelectObject(*m_buffer);
- m_mainDc->Blit( 0, 0,
- m_buffer->GetWidth(), m_buffer->GetHeight(), bufferDc,
- -x, -y );
- m_mainDc = NULL;
- m_buffer = NULL;
- delete bufferDc;
- }
+ // now that the DC is valid we can inherit the attributes (fonts, colours,
+ // layout direction, ...) from the original DC
+ if ( m_dc && m_dc->IsOk() )
+ CopyAttributes(*m_dc);
}
-void wxBufferedDC::PrepareBuffer(wxWindow* win, const wxSize& area)
+void wxBufferedDC::UnMask()
{
- m_buffer = gs_sharedDCBufferManager.GetBuffer(win, area);
-}
+ wxCHECK_RET( m_dc, wxT("no underlying wxDC?") );
+ wxASSERT_MSG( m_buffer && m_buffer->IsOk(), wxT("invalid backing store") );
-void wxBufferedDC::UseBuffer()
-{
- wxASSERT(m_buffer);
+ wxCoord x = 0,
+ y = 0;
- wxMemoryDC* memoryDc = new wxMemoryDC(m_mainDc);
- memoryDc->SelectObject(*m_buffer);
+ // Ensure the scale matches the device
+ SetUserScale(1.0, 1.0);
- AttachDC(memoryDc);
-}
+ if ( m_style & wxBUFFER_CLIENT_AREA )
+ GetDeviceOrigin(&x, &y);
+ // It's possible that the buffer may be bigger than the area that needs to
+ // be drawn (the client size of the window is smaller than the bitmap, or
+ // a shared bitmap has been reused for a smaller area, etc.) so avoid
+ // blitting too much if possible, but only use the real DC size if the
+ // wxBUFFER_VIRTUAL_AREA style is not set.
+ int width = m_area.GetWidth(),
+ height = m_area.GetHeight();
+ if (! m_style & wxBUFFER_VIRTUAL_AREA)
+ {
+ int widthDC,
+ heightDC;
+ m_dc->GetSize(&widthDC, &heightDC);
+ width = wxMin(width, widthDC);
+ height = wxMin(height, heightDC);
+ }
+
+ m_dc->Blit(0, 0, width, height, this, -x, -y);
+ m_dc = NULL;
+
+ if ( m_style & wxBUFFER_USES_SHARED_BUFFER )
+ wxSharedDCBufferManager::ReleaseBuffer(m_buffer);
+}