Ignore failure when deleting something that might not exist

[wxWidgets.git] / samples / image / image.cpp

diff --git a/samples/image/image.cpp b/samples/image/image.cpp
index ce48fb032ce459e9644e95822cdac1cf79575e2e..7b17838bd525c529a2afa16b04103564669444ed 100644 (file)
--- a/samples/image/image.cpp
+++ b/samples/image/image.cpp
@@ -34,9 +34,11 @@ public:
     MyCanvas( wxWindow *parent, wxWindowID, const wxPoint &pos, const wxSize &size );
     ~MyCanvas();
     void OnPaint( wxPaintEvent &event );
+    void CreateAntiAliasedBitmap();
 
     wxBitmap  *my_horse;
     wxBitmap  *my_square;
+    wxBitmap  *my_anti;
 
     DECLARE_DYNAMIC_CLASS(MyCanvas)
     DECLARE_EVENT_TABLE()
@@ -78,10 +80,14 @@ BEGIN_EVENT_TABLE(MyCanvas, wxScrolledWindow)
   EVT_PAINT(MyCanvas::OnPaint)
 END_EVENT_TABLE()
 
-MyCanvas::MyCanvas( wxWindow *parent, const wxWindowID id,
+MyCanvas::MyCanvas( wxWindow *parent, wxWindowID id,
                     const wxPoint &pos, const wxSize &size )
         : wxScrolledWindow( parent, id, pos, size, wxSUNKEN_BORDER )
 {
+  my_horse = (wxBitmap*) NULL;
+  my_square = (wxBitmap*) NULL;
+  my_anti = (wxBitmap*) NULL;
+
   SetBackgroundColour(* wxWHITE);
 
   wxBitmap bitmap( 100, 100 );
@@ -99,32 +105,23 @@ MyCanvas::MyCanvas( wxWindow *parent, const wxWindowID id,
   dir = wxString("../");
 #endif
 
-//#ifdef __WXMOTIF__
-  dir = wxString("../");
-//#endif
-
-#ifndef __WXMOTIF__
   wxImage image( bitmap );
   image.SaveFile( dir + wxString("test.png"), wxBITMAP_TYPE_PNG );
-#else
-  wxImage image;
-#endif
   
   image.LoadFile( dir + wxString("horse.png"), wxBITMAP_TYPE_PNG );
   my_horse = new wxBitmap( image.ConvertToBitmap() );
   
-#ifndef __WXMOTIF__
   image.LoadFile( dir + wxString("test.png"), wxBITMAP_TYPE_PNG );
   my_square = new wxBitmap( image.ConvertToBitmap() );
-#endif
+
+  CreateAntiAliasedBitmap();
 }
 
 MyCanvas::~MyCanvas()
 {
   delete my_horse;
-#ifndef __WXMOTIF__
   delete my_square;
-#endif
+  delete my_anti;
 }
 
 void MyCanvas::OnPaint( wxPaintEvent &WXUNUSED(event) )
@@ -132,17 +129,65 @@ void MyCanvas::OnPaint( wxPaintEvent &WXUNUSED(event) )
   wxPaintDC dc( this );
   PrepareDC( dc );
 
-#ifndef __WXMOTIF__
-  dc.DrawText( "Loaded image", 30, 100 );
-  if (my_square->Ok()) dc.DrawBitmap( *my_square, 30, 120 );
+  dc.DrawText( "Loaded image", 30, 10 );
+  if (my_square && my_square->Ok()) dc.DrawBitmap( *my_square, 30, 30 );
 
-  dc.DrawText( "Drawn directly", 150, 100 );
+  dc.DrawText( "Drawn directly", 150, 10 );
   dc.SetBrush( wxBrush( "orange", wxSOLID ) );
   dc.SetPen( *wxWHITE_PEN );
-  dc.DrawRectangle( 150, 120, 100, 100 );
-#endif
+  dc.DrawRectangle( 150, 30, 100, 100 );
 
-  if (my_horse->Ok()) dc.DrawBitmap( *my_horse, 30, 240 );
+  if (my_anti && my_anti->Ok()) dc.DrawBitmap( *my_anti, 250, 140 );
+  
+  if (my_horse && my_horse->Ok()) dc.DrawBitmap( *my_horse, 30, 140 );
+}
+
+void MyCanvas::CreateAntiAliasedBitmap()
+{
+  wxBitmap bitmap( 300, 300 );
+
+  wxMemoryDC dc;
+
+  dc.SelectObject( bitmap );
+
+  dc.Clear();
+  
+  dc.SetFont( wxFont( 24, wxDECORATIVE, wxDEFAULT, wxDEFAULT ) );
+  dc.SetTextForeground( "RED" );
+  dc.DrawText( "This is anti-aliased Text.", 20, 20 );
+  dc.DrawText( "And a Rectangle.", 20, 60 );
+  
+  dc.SetBrush( *wxRED_BRUSH );
+  dc.DrawRoundedRectangle( 20, 100, 200, 180, 20 );
+  
+  wxImage original( bitmap );
+  wxImage anti( 150, 150 );
+
+  /* This is quite slow, but safe. Use wxImage::GetData() for speed instead. */
+  
+  for (int y = 1; y < 149; y++)
+    for (int x = 1; x < 149; x++)
+    {
+       int red = original.GetRed( x*2, y*2 ) +
+                 original.GetRed( x*2-1, y*2 ) + 
+                 original.GetRed( x*2, y*2+1 ) + 
+                 original.GetRed( x*2+1, y*2+1 );
+       red = red/4; 
+       
+       int green = original.GetGreen( x*2, y*2 ) +
+                   original.GetGreen( x*2-1, y*2 ) + 
+                   original.GetGreen( x*2, y*2+1 ) + 
+                   original.GetGreen( x*2+1, y*2+1 );
+       green = green/4; 
+       
+       int blue = original.GetBlue( x*2, y*2 ) +
+                  original.GetBlue( x*2-1, y*2 ) + 
+                  original.GetBlue( x*2, y*2+1 ) + 
+                  original.GetBlue( x*2+1, y*2+1 );
+       blue = blue/4; 
+       anti.SetRGB( x, y, red, green, blue );
+    }
+  my_anti = new wxBitmap( anti.ConvertToBitmap() );
 }
 
 // MyFrame
@@ -196,8 +241,6 @@ void MyFrame::OnAbout( wxCommandEvent &WXUNUSED(event) )
 
 bool MyApp::OnInit()
 {
-  wxImage::AddHandler( new wxPNGHandler );
-
   wxFrame *frame = new MyFrame();
   frame->Show( TRUE );