wxWidgets/samples/png/pngdemo.cpp

213 lines
5.5 KiB
C++

/////////////////////////////////////////////////////////////////////////////
// Name: pngdemo.cpp
// Purpose: Demos PNG reading
// Author: Julian Smart
// Modified by:
// Created: 04/01/98
// RCS-ID: $Id$
// Copyright: (c) Julian Smart
// Licence: wxWindows license
/////////////////////////////////////////////////////////////////////////////
#ifdef __GNUG__
#pragma implementation "pngdemo.h"
#endif
// For compilers that support precompilation, includes "wx.h".
#include "wx/wxprec.h"
#ifdef __BORLANDC__
#pragma hdrstop
#endif
#include "wx/image.h"
#include "pngdemo.h"
MyFrame *frame = (MyFrame *) NULL;
wxBitmap *g_TestBitmap = (wxBitmap *) NULL;
IMPLEMENT_APP(MyApp)
bool MyApp::OnInit(void)
{
wxImage::AddHandler(new wxPNGHandler);
// Create the main frame window
frame = new MyFrame((wxFrame *) NULL, _T("wxPNGBitmap Demo"), wxPoint(0, 0), wxSize(300, 300));
#if wxUSE_STATUSBAR
// Give it a status line
frame->CreateStatusBar(2);
#endif // wxUSE_STATUSBAR
// Make a menubar
wxMenu *file_menu = new wxMenu;
wxMenu *help_menu = new wxMenu;
file_menu->Append(PNGDEMO_LOAD_FILE, _T("&Load file"), _T("Load file"));
file_menu->Append(PNGDEMO_SAVE_FILE, _T("&Save file"), _T("Save file"));
file_menu->Append(PNGDEMO_QUIT, _T("E&xit"), _T("Quit program"));
help_menu->Append(PNGDEMO_ABOUT, _T("&About"), _T("About PNG demo"));
wxMenuBar *menu_bar = new wxMenuBar;
menu_bar->Append(file_menu, _T("&File"));
menu_bar->Append(help_menu, _T("&Help"));
// Associate the menu bar with the frame
frame->SetMenuBar(menu_bar);
MyCanvas *canvas = new MyCanvas(frame, wxPoint(0, 0), wxSize(100, 100));
// Give it scrollbars: the virtual canvas is 20 * 50 = 1000 pixels in each direction
// canvas->SetScrollbars(20, 20, 50, 50, 4, 4);
frame->canvas = canvas;
frame->Show(true);
#if wxUSE_STATUSBAR
frame->SetStatusText(_T("Hello, wxWidgets"));
#endif // wxUSE_STATUSBAR
return true;
}
BEGIN_EVENT_TABLE(MyFrame, wxFrame)
EVT_MENU(PNGDEMO_QUIT, MyFrame::OnQuit)
EVT_MENU(PNGDEMO_ABOUT, MyFrame::OnAbout)
EVT_MENU(PNGDEMO_LOAD_FILE, MyFrame::OnLoadFile)
EVT_MENU(PNGDEMO_SAVE_FILE, MyFrame::OnSaveFile)
END_EVENT_TABLE()
// Define my frame constructor
MyFrame::MyFrame(wxFrame *frame, const wxString& title, const wxPoint& pos, const wxSize& size):
wxFrame(frame, wxID_ANY, title, pos, size)
{
canvas = (MyCanvas *) NULL;
}
// frame destructor
MyFrame::~MyFrame()
{
if (g_TestBitmap)
{
delete g_TestBitmap;
g_TestBitmap = (wxBitmap *) NULL;
}
}
void MyFrame::OnQuit(wxCommandEvent& WXUNUSED(event))
{
Close(true);
}
void MyFrame::OnAbout(wxCommandEvent& WXUNUSED(event))
{
(void)wxMessageBox(_T("PNG demo\nJulian Smart (c) 1998"),
_T("About PNG Demo"), wxOK);
}
void MyFrame::OnSaveFile(wxCommandEvent& WXUNUSED(event))
{
wxString f = wxFileSelector( wxT("Save Image"), (const wxChar *)NULL,
(const wxChar *)NULL,
wxT("png"), wxT("PNG files (*.png)|*.png") );
if (f == _T("")) return;
wxBitmap *backstore = new wxBitmap( 150, 150 );
wxMemoryDC memDC;
memDC.SelectObject( *backstore );
memDC.Clear();
memDC.SetBrush( *wxBLACK_BRUSH );
memDC.SetPen( *wxWHITE_PEN );
memDC.DrawRectangle( 0, 0, 150, 150 );
memDC.SetPen( *wxBLACK_PEN );
memDC.DrawLine( 0, 0, 0, 10 );
memDC.SetTextForeground( *wxWHITE );
memDC.DrawText( _T("This is a memory dc."), 10, 10 );
memDC.SelectObject( wxNullBitmap );
backstore->SaveFile( f, wxBITMAP_TYPE_PNG, (wxPalette*)NULL );
delete backstore;
}
void MyFrame::OnLoadFile(wxCommandEvent& WXUNUSED(event))
{
// Show file selector.
wxString f = wxFileSelector(wxT("Open Image"), (const wxChar *) NULL,
(const wxChar *) NULL, wxT("png"),
wxT("PNG files (*.png)|*.png"));
if (f == _T(""))
return;
if ( g_TestBitmap )
delete g_TestBitmap;
g_TestBitmap = new wxBitmap(f, wxBITMAP_TYPE_PNG);
if (!g_TestBitmap->Ok())
{
delete g_TestBitmap;
g_TestBitmap = (wxBitmap *) NULL;
}
canvas->Refresh();
}
BEGIN_EVENT_TABLE(MyCanvas, wxScrolledWindow)
EVT_PAINT(MyCanvas::OnPaint)
END_EVENT_TABLE()
// Define a constructor for my canvas
MyCanvas::MyCanvas(wxWindow *parent, const wxPoint& pos, const wxSize& size):
wxScrolledWindow(parent, wxID_ANY, pos, size)
{
}
// Define the repainting behaviour
void MyCanvas::OnPaint(wxPaintEvent& WXUNUSED(event))
{
wxPaintDC dc(this);
dc.SetPen(* wxRED_PEN);
int i;
for ( i = 0; i < 500; i += 10)
{
dc.DrawLine(0, i, 800, i);
}
if ( g_TestBitmap && g_TestBitmap->Ok() )
{
wxMemoryDC memDC;
if ( g_TestBitmap->GetPalette() )
{
memDC.SetPalette(* g_TestBitmap->GetPalette());
dc.SetPalette(* g_TestBitmap->GetPalette());
}
memDC.SelectObject(* g_TestBitmap);
// Normal, non-transparent blitting
dc.Blit(20, 20, g_TestBitmap->GetWidth(), g_TestBitmap->GetHeight(), & memDC, 0, 0, wxCOPY, false);
memDC.SelectObject(wxNullBitmap);
}
if ( g_TestBitmap && g_TestBitmap->Ok() )
{
wxMemoryDC memDC;
memDC.SelectObject(* g_TestBitmap);
// Transparent blitting if there's a mask in the bitmap
dc.Blit(20 + g_TestBitmap->GetWidth() + 20, 20, g_TestBitmap->GetWidth(), g_TestBitmap->GetHeight(), & memDC,
0, 0, wxCOPY, true);
memDC.SelectObject(wxNullBitmap);
}
}