src/common/imagpnm.cpp

   1 /////////////////////////////////////////////////////////////////////////////
   2 // Name:        imagpnm.cpp
   3 // Purpose:     wxImage PNM handler
   4 // Author:      Sylvain Bougnoux
   5 // RCS-ID:      $Id$
   6 // Copyright:   (c) Sylvain Bougnoux
   7 // Licence:     wxWindows licence
   8 /////////////////////////////////////////////////////////////////////////////
   9
  10 /*
  11    We don't put pragma implement in this file because it is already present in
  12    src/common/image.cpp
  13 */
  14
  15 // For compilers that support precompilation, includes "wx.h".
  16 #include "wx/wxprec.h"
  17
  18 #ifdef __BORLANDC__
  19 #pragma hdrstop
  20 #endif
  21
  22 #include "wx/image.h"
  23 #include "wx/log.h"
  24 #include "wx/txtstrm.h"
  25
  26 #if wxUSE_PNM
  27
  28 #ifdef __WXMSW__
  29 #include <windows.h>
  30 #endif
  31
  32 //-----------------------------------------------------------------------------
  33 // wxBMPHandler
  34 //-----------------------------------------------------------------------------
  35
  36 #if !USE_SHARED_LIBRARIES
  37 IMPLEMENT_DYNAMIC_CLASS(wxPNMHandler,wxImageHandler)
  38 #endif
  39
  40 #if wxUSE_STREAMS
  41
  42 //#include <stream.h> // for cout
  43
  44 void Skip_Comment(wxInputStream &stream)
  45 {
  46   wxString line;
  47   wxTextInputStream text_stream(stream);
  48
  49   if (stream.Peek()==_T('#'))
  50     {
  51       text_stream >> line;
  52       Skip_Comment(stream);
  53     }
  54 }
  55
  56 bool wxPNMHandler::LoadFile( wxImage *image, wxInputStream& stream, bool WXUNUSED(verbose) )
  57 {
  58     wxUint32  width, height;
  59     wxUint16  maxval;
  60     wxString  line;
  61     char      c(0);
  62
  63     image->Destroy();
  64
  65     /*
  66      * Read the PNM header
  67      */
  68
  69     wxBufferedInputStream buf_stream(stream);
  70     wxTextInputStream text_stream(buf_stream);
  71
  72     Skip_Comment(buf_stream);
  73     if (buf_stream.GetC()==_T('P')) c=buf_stream.GetC();
  74
  75     switch (c)
  76       {
  77       case _T('2'):
  78         wxLogError(_T("Loading Grey Ascii PNM image is not yet implemented."));
  79         return FALSE;
  80       case _T('5'):
  81         wxLogError(_T("Loading Grey Raw PNM image is not yet implemented."));
  82         return FALSE;
  83       case _T('3'): case _T('6'): break;
  84         default :
  85         wxLogError(_T("Loading PNM image : file not recognized."));
  86         return FALSE;
  87       }
  88
  89     text_stream >> line; // for the \n
  90     Skip_Comment(buf_stream);
  91     text_stream >> width >> height ;
  92     Skip_Comment(buf_stream);
  93     text_stream >> maxval;
  94
  95     //cout << line << " " << width << " " << height << " " << maxval << endl;
  96     image->Create( width, height );
  97     unsigned char *ptr = image->GetData();
  98     if (!ptr)
  99     {
 100         wxLogError( _T("Cannot allocate RAM for RGB data in PNM file.") );
 101         return FALSE;
 102     }
 103
 104    if (c=='3') // Ascii RBG
 105       {
 106         wxUint32 value, size=3*width*height;
 107         for (wxUint32 i=0; i<size; ++i)
 108           {
 109             //this is very slow !!!
 110             //I wonder how we can make any better ?
 111             value=text_stream.Read32();
 112             *ptr++=(unsigned char)value;
 113
 114             if (buf_stream.LastError()!=wxSTREAM_NOERROR)
 115               {
 116                 wxLogError(_T("Loading PNM image : file seems truncated."));
 117                 return FALSE;
 118               }
 119           }
 120       }
 121     if (c=='6') // Raw RGB
 122       buf_stream.Read( ptr, 3*width*height );
 123
 124     image->SetMask( FALSE );
 125
 126     return (buf_stream.LastError()==wxStream_NOERROR || buf_stream.LastError()==wxStream_EOF);
 127 }
 128
 129 bool wxPNMHandler::SaveFile( wxImage *image, wxOutputStream& stream, bool WXUNUSED(verbose) )
 130 {
 131     wxTextOutputStream text_stream(stream);
 132
 133     //text_stream << "P6" << endl
 134     //<< image->GetWidth() << " " << image->GetHeight() << endl
 135     //<< "255" << endl;
 136     text_stream << "P6\n" << image->GetWidth() << " " << image->GetHeight() << "\n255\n";
 137     stream.Write(image->GetData(),3*image->GetWidth()*image->GetHeight());
 138
 139     return (stream.LastError()==wxStream_NOERROR);
 140 }
 141
 142 bool wxPNMHandler::CanRead( wxInputStream& stream )
 143 {
 144     off_t pos=stream.TellI();
 145
 146     Skip_Comment(stream);
 147
 148     if (stream.GetC()==_T('P'))
 149       switch (stream.GetC())
 150         {
 151         case _T('3'): case _T('6'):
 152           stream.SeekI(pos);
 153           return TRUE;
 154         }
 155
 156     stream.SeekI(pos);
 157     return FALSE;
 158 }
 159
 160
 161 #endif // wxUSE_STREAMS
 162
 163 #endif // wxUSE_PNM
 164