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