make construct simpler

[wxWidgets.git] / src / common / imaggif.cpp

diff --git a/src/common/imaggif.cpp b/src/common/imaggif.cpp
index c6a775e15cde7d2294bc697557870c731bd1c595..3a64963f922fbda4bbf7455b068d3cd4e521460f 100644 (file)
--- a/src/common/imaggif.cpp
+++ b/src/common/imaggif.cpp
@@ -1,19 +1,18 @@
 /////////////////////////////////////////////////////////////////////////////
 // Name:        imaggif.cpp
 // Purpose:     wxGIFHandler
-// Author:      Vaclav Slavik
-//              Based on wxGIFDecoder by Guillermo Rodriguez Garcia
+// Author:      Vaclav Slavik & Guillermo Rodriguez Garcia
 // RCS-ID:      $Id$
+// Copyright:   (c) 1999 Vaclav Slavik & Guillermo Rodriguez Garcia
 // Licence:     wxWindows licence
 /////////////////////////////////////////////////////////////////////////////
 
-/*
-We don't put pragma implement in this file because it is already present in
-src/common/image.cpp
-*/
+#if defined(__GNUG__) && !defined(NO_GCC_PRAGMA)
+#pragma implementation "imaggif.h"
+#endif
 
 // For compilers that support precompilation, includes "wx.h".
-#include <wx/wxprec.h>
+#include "wx/wxprec.h"
 
 #ifdef __BORLANDC__
 #  pragma hdrstop
@@ -23,56 +22,104 @@ src/common/image.cpp
 #  include "wx/defs.h"
 #endif
 
-#include "wx/image.h"
-// #include "wx/imaggif.h"
+#if wxUSE_IMAGE && wxUSE_GIF
+
+#include "wx/imaggif.h"
 #include "wx/gifdecod.h"
 #include "wx/wfstream.h"
-#include "wx/module.h"
 #include "wx/log.h"
+#include "wx/intl.h"
 
 IMPLEMENT_DYNAMIC_CLASS(wxGIFHandler,wxImageHandler)
 
-#if wxUSE_STREAMS
-
 //-----------------------------------------------------------------------------
 // wxGIFHandler
 //-----------------------------------------------------------------------------
 
-bool wxGIFHandler::LoadFile( wxImage *image, wxInputStream& stream, bool WXUNUSED(verbose) )
+#if wxUSE_STREAMS
+
+bool wxGIFHandler::LoadFile(wxImage *image, wxInputStream& stream,
+                            bool verbose, int index)
 {
     wxGIFDecoder *decod;
-    bool ok;
+    int error;
+    bool ok = TRUE;
 
+//    image->Destroy();
     decod = new wxGIFDecoder(&stream, TRUE);
-    
-    if (decod->ReadGIF() != E_OK)
+    error = decod->ReadGIF();
+
+    if ((error != wxGIF_OK) && (error != wxGIF_TRUNCATED))
     {
-        wxLogDebug(_T("Error reading GIF"));
+        if (verbose)
+        {
+            switch (error)
+            {
+                case wxGIF_INVFORMAT:
+                    wxLogError(_("GIF: error in GIF image format."));
+                    break;
+                case wxGIF_MEMERR:
+                    wxLogError(_("GIF: not enough memory."));
+                    break;
+                default:
+                    wxLogError(_("GIF: unknown error!!!"));
+                    break;
+            }
+        }
         delete decod;
         return FALSE;
     }
 
-    image->Destroy();
-    ok = decod->ConvertToImage(image);
+    if ((error == wxGIF_TRUNCATED) && verbose)
+    {
+        wxLogError(_("GIF: data stream seems to be truncated."));
+        /* go on; image data is OK */
+    }
+
+    if (index != -1)
+    {
+        // We're already on index = 0 by default. So no need
+        // to call GoFrame(0) then. On top of that GoFrame doesn't
+        // accept an index of 0. (Instead GoFirstFrame() should be used)
+        // Also if the gif image has only one frame, calling GoFrame(0)
+        // fails because GoFrame() only works with gif animations.
+        // (It fails if IsAnimation() returns FALSE)
+        // All valid reasons to NOT call GoFrame when index equals 0.
+        if (index != 0)
+        {
+            ok = decod->GoFrame(index);
+        }
+    }
+
+    if (ok)
+    {
+        ok = decod->ConvertToImage(image);
+    }
+    else
+    {
+        wxLogError(_("GIF: Invalid gif index."));
+    }
 
     delete decod;
+
     return ok;
 }
 
 bool wxGIFHandler::SaveFile( wxImage * WXUNUSED(image),
                              wxOutputStream& WXUNUSED(stream), bool verbose )
 {
-    if (verbose) wxLogDebug(_T("wxGIFHandler is read-only!!"));
+    if (verbose)
+        wxLogDebug(wxT("GIF: the handler is read-only!!"));
+
     return FALSE;
 }
 
-bool wxGIFHandler::CanRead( wxInputStream& stream )
+bool wxGIFHandler::DoCanRead( wxInputStream& stream )
 {
-    unsigned char hdr[5];
-    
-    stream.Read(&hdr, 5);
-    stream.SeekI(-5, wxFromCurrent);
-    return (hdr[0] == 'G' && hdr[1] == 'I' && hdr[2] == 'F' && hdr[3] == '8' && hdr[4] == '9');
+    wxGIFDecoder decod(&stream);
+    return decod.CanRead();
 }
 
-#endif
+#endif  // wxUSE_STREAMS
+
+#endif  // wxUSE_GIF