samples/png/pngdemo.cpp

   1 /////////////////////////////////////////////////////////////////////////////
   2 // Name:        pngdemo.cpp
   3 // Purpose:     Demos PNG reading
   4 // Author:      Julian Smart
   5 // Modified by:
   6 // Created:     04/01/98
   7 // RCS-ID:      $Id$
   8 // Copyright:   (c) Julian Smart and Markus Holzem
   9 // Licence:     wxWindows license
  10 /////////////////////////////////////////////////////////////////////////////
  11
  12 #ifdef __GNUG__
  13 #pragma implementation "pngdemo.h"
  14 #endif
  15
  16 // For compilers that support precompilation, includes "wx.h".
  17 #include "wx/wxprec.h"
  18
  19 #ifdef __BORLANDC__
  20 #pragma hdrstop
  21 #endif
  22
  23 #ifdef __WXMSW__
  24 #include <wx/pnghand.h>
  25 // #include <wx/xpmhand.h>
  26 #endif
  27
  28 #include "pngdemo.h"
  29
  30 MyFrame   *frame = (MyFrame *) NULL;
  31 wxBitmap  *g_TestBitmap = (wxBitmap *) NULL;
  32
  33 IMPLEMENT_APP(MyApp)
  34
  35 MyApp::MyApp()
  36 {
  37 }
  38
  39 bool MyApp::OnInit(void)
  40 {
  41 #ifdef __WXMSW__
  42   wxBitmap::AddHandler(new wxPNGFileHandler);
  43 //  wxBitmap::AddHandler(new wxXPMFileHandler);
  44 //  wxBitmap::AddHandler(new wxXPMDataHandler);
  45 #endif
  46
  47   // Create the main frame window
  48   frame = new MyFrame((wxFrame *) NULL, "wxPNGBitmap Demo", wxPoint(0, 0), wxSize(300, 300));
  49
  50   // Give it a status line
  51   frame->CreateStatusBar(2);
  52
  53   // Make a menubar
  54   wxMenu *file_menu = new wxMenu;
  55   wxMenu *help_menu = new wxMenu;
  56
  57   file_menu->Append(PNGDEMO_LOAD_FILE, "&Load file",                "Load file");
  58   file_menu->Append(PNGDEMO_SAVE_FILE, "&Save file",                "Save file");
  59   file_menu->Append(PNGDEMO_QUIT, "E&xit",                "Quit program");
  60   help_menu->Append(PNGDEMO_ABOUT, "&About",              "About PNG demo");
  61
  62   wxMenuBar *menu_bar = new wxMenuBar;
  63
  64   menu_bar->Append(file_menu, "&File");
  65   menu_bar->Append(help_menu, "&Help");
  66
  67   // Associate the menu bar with the frame
  68   frame->SetMenuBar(menu_bar);
  69
  70   MyCanvas *canvas = new MyCanvas(frame, wxPoint(0, 0), wxSize(100, 100));
  71
  72   // Give it scrollbars: the virtual canvas is 20 * 50 = 1000 pixels in each direction
  73 //  canvas->SetScrollbars(20, 20, 50, 50, 4, 4);
  74   frame->canvas = canvas;
  75
  76   frame->Show(TRUE);
  77
  78   frame->SetStatusText("Hello, wxWindows");
  79
  80   return TRUE;
  81 }
  82
  83 BEGIN_EVENT_TABLE(MyFrame, wxFrame)
  84     EVT_MENU(PNGDEMO_QUIT,      MyFrame::OnQuit)
  85     EVT_MENU(PNGDEMO_ABOUT,     MyFrame::OnAbout)
  86     EVT_MENU(PNGDEMO_LOAD_FILE, MyFrame::OnLoadFile)
  87     EVT_MENU(PNGDEMO_SAVE_FILE, MyFrame::OnSaveFile)
  88 END_EVENT_TABLE()
  89
  90 // Define my frame constructor
  91 MyFrame::MyFrame(wxFrame *frame, const wxString& title, const wxPoint& pos, const wxSize& size):
  92   wxFrame(frame, -1, title, pos, size)
  93 {
  94   canvas = (MyCanvas *) NULL;
  95 }
  96
  97 void MyFrame::OnQuit(wxCommandEvent& WXUNUSED(event))
  98 {
  99     Close(TRUE);
 100 }
 101
 102 void MyFrame::OnAbout(wxCommandEvent& WXUNUSED(event))
 103 {
 104     (void)wxMessageBox("PNG demo\nJulian Smart (c) 1998",
 105             "About PNG Demo", wxOK);
 106 }
 107
 108 void MyFrame::OnSaveFile(wxCommandEvent& WXUNUSED(event))
 109 {
 110   wxString f = wxFileSelector( "Save Image", (const char *)NULL, (const char *)NULL,
 111                             "png", "PNG files (*.png)|*.png" );
 112
 113   if (f == "")  return;
 114
 115   wxBitmap *backstore = new wxBitmap( 150, 150 );
 116
 117   wxMemoryDC memDC;
 118   memDC.SelectObject( *backstore );
 119   memDC.Clear();
 120   memDC.SetBrush( *wxBLACK_BRUSH );
 121   memDC.SetPen( *wxWHITE_PEN );
 122   memDC.DrawRectangle( 0, 0, 150, 150 );
 123   memDC.SetPen( *wxBLACK_PEN );
 124   memDC.DrawLine( 0, 0, 0, 10 );
 125   memDC.SetTextForeground( *wxWHITE );
 126   memDC.DrawText( "This is a memory dc.", 10, 10 );
 127
 128   memDC.SelectObject( wxNullBitmap );
 129
 130   backstore->SaveFile( f, wxBITMAP_TYPE_PNG, (wxPalette*)NULL );
 131
 132   delete backstore;
 133 }
 134
 135 void MyFrame::OnLoadFile(wxCommandEvent& WXUNUSED(event))
 136 {
 137         // Show file selector.
 138         wxString f = wxFileSelector("Open Image", (const char *) NULL, (const char *) NULL,"png",
 139                   "PNG files (*.png)|*.png");
 140
 141         if (f == "")
 142           return;
 143
 144     if ( g_TestBitmap )
 145         delete g_TestBitmap;
 146     g_TestBitmap = new wxBitmap(f, wxBITMAP_TYPE_PNG);
 147     if (!g_TestBitmap->Ok())
 148     {
 149         delete g_TestBitmap;
 150         g_TestBitmap = (wxBitmap *) NULL;
 151     }
 152
 153     canvas->Refresh();
 154 }
 155
 156 BEGIN_EVENT_TABLE(MyCanvas, wxScrolledWindow)
 157     EVT_PAINT(MyCanvas::OnPaint)
 158 END_EVENT_TABLE()
 159
 160 // Define a constructor for my canvas
 161 MyCanvas::MyCanvas(wxWindow *parent, const wxPoint& pos, const wxSize& size):
 162  wxScrolledWindow(parent, -1, pos, size)
 163 {
 164 }
 165
 166 MyCanvas::~MyCanvas(void)
 167 {
 168 }
 169
 170 // Define the repainting behaviour
 171 void MyCanvas::OnPaint(wxPaintEvent& WXUNUSED(event))
 172 {
 173   wxPaintDC dc(this);
 174   dc.SetPen(* wxRED_PEN);
 175
 176   int i;
 177   for ( i = 0; i < 500; i += 10)
 178   {
 179     dc.DrawLine(0, i, 800, i);
 180   }
 181   if ( g_TestBitmap && g_TestBitmap->Ok() )
 182   {
 183     wxMemoryDC memDC;
 184     if ( g_TestBitmap->GetPalette() )
 185     {
 186         memDC.SetPalette(* g_TestBitmap->GetPalette());
 187         dc.SetPalette(* g_TestBitmap->GetPalette());
 188     }
 189     memDC.SelectObject(* g_TestBitmap);
 190
 191     // Normal, non-transparent blitting
 192     dc.Blit(20, 20, g_TestBitmap->GetWidth(), g_TestBitmap->GetHeight(), & memDC, 0, 0, wxCOPY, FALSE);
 193
 194     memDC.SelectObject(wxNullBitmap);
 195   }
 196
 197   if ( g_TestBitmap && g_TestBitmap->Ok() )
 198   {
 199     wxMemoryDC memDC;
 200     memDC.SelectObject(* g_TestBitmap);
 201
 202     // Transparent blitting if there's a mask in the bitmap
 203     dc.Blit(20 + g_TestBitmap->GetWidth() + 20, 20, g_TestBitmap->GetWidth(), g_TestBitmap->GetHeight(), & memDC,
 204       0, 0, wxCOPY, TRUE);
 205
 206     memDC.SelectObject(wxNullBitmap);
 207   }
 208 }
 209
 210