// Purpose: wxGIFDecoder, GIF reader for wxImage and wxAnimation
// Author: Guillermo Rodriguez Garcia <guille@iies.es>
// Version: 3.02
-// Last rev: 1999/08/18
-// Copyright: (c) Guillermo Rodriguez Garcia
+// CVS-ID: $Id$
+// Copyright: (c) 1999 Guillermo Rodriguez Garcia
// Licence: wxWindows licence
/////////////////////////////////////////////////////////////////////////////
#ifndef _WX_GIFDECOD_H
#define _WX_GIFDECOD_H
-#ifdef __GNUG__
+#if defined(__GNUG__) && !defined(NO_GCC_PRAGMA)
#pragma interface "gifdecod.h"
#endif
#include "wx/setup.h"
-#if wxUSE_STREAMS
+#if wxUSE_STREAMS && wxUSE_GIF
+
#include "wx/stream.h"
#include "wx/image.h"
-typedef struct _IMAGEN
+// --------------------------------------------------------------------------
+// Constants
+// --------------------------------------------------------------------------
+
+// Error codes:
+// Note that the error code wxGIF_TRUNCATED means that the image itself
+// is most probably OK, but the decoder didn't reach the end of the data
+// stream; this means that if it was not reading directly from file,
+// the stream will not be correctly positioned. the
+//
+enum
+{
+ wxGIF_OK = 0, /* everything was OK */
+ wxGIF_INVFORMAT, /* error in gif header */
+ wxGIF_MEMERR, /* error allocating memory */
+ wxGIF_TRUNCATED /* file appears to be truncated */
+};
+
+// Disposal method
+// Experimental; subject to change.
+//
+enum
{
+ wxGIF_D_UNSPECIFIED = -1, /* not specified */
+ wxGIF_D_DONOTDISPOSE = 0, /* do not dispose */
+ wxGIF_D_TOBACKGROUND = 1, /* restore to background colour */
+ wxGIF_D_TOPREVIOUS = 2 /* restore to previous image */
+};
+
+
+#define MAX_BLOCK_SIZE 256 /* max. block size */
+
+
+// --------------------------------------------------------------------------
+// wxGIFDecoder class
+// --------------------------------------------------------------------------
+
+// internal class for storing GIF image data
+class GIFImage
+{
+public:
+ // def ctor
+ GIFImage();
+
unsigned int w; /* width */
unsigned int h; /* height */
unsigned int left; /* x coord (in logical screen) */
long delay; /* delay in ms (-1 = unused) */
unsigned char *p; /* bitmap */
unsigned char *pal; /* palette */
- struct _IMAGEN *next; /* next image */
- struct _IMAGEN *prev; /* prev image */
-} IMAGEN;
-
+ GIFImage *next; /* next image */
+ GIFImage *prev; /* prev image */
-/* disposal method */
-#define D_UNSPECIFIED -1 /* not specified */
-#define D_DONOTDISPOSE 0 /* do not dispose */
-#define D_TOBACKGROUND 1 /* restore to background colour */
-#define D_TOPREVIOUS 2 /* restore to previous image */
-
-/* error codes */
-#define E_OK 0 /* everything was OK */
-#define E_ARCHIVO -1 /* error opening file */
-#define E_FORMATO -2 /* error in gif header */
-#define E_MEMORIA -3 /* error allocating memory */
+ DECLARE_NO_COPY_CLASS(GIFImage)
+};
-class wxGIFDecoder
+class WXDLLEXPORT wxGIFDecoder
{
private:
- /* logical screen */
+ // logical screen
unsigned int m_screenw; /* logical screen width */
unsigned int m_screenh; /* logical screen height */
int m_background; /* background color (-1 = none) */
- /* image data */
+ // image data
bool m_anim; /* animated GIF */
int m_nimages; /* number of images */
int m_image; /* current image */
- IMAGEN *m_pimage; /* pointer to current image */
- IMAGEN *m_pfirst; /* pointer to first image */
- IMAGEN *m_plast; /* pointer to last image */
+ GIFImage *m_pimage; /* pointer to current image */
+ GIFImage *m_pfirst; /* pointer to first image */
+ GIFImage *m_plast; /* pointer to last image */
- /* decoder state vars */
+ // decoder state vars
int m_restbits; /* remaining valid bits */
unsigned int m_restbyte; /* remaining bytes in this block */
unsigned int m_lastbyte; /* last byte read */
+ unsigned char m_buffer[MAX_BLOCK_SIZE]; /* buffer for reading */
+ unsigned char *m_bufp; /* pointer to next byte in buffer */
- wxInputStream *m_f; /* input file */
+ // input stream
+ wxInputStream *m_f; /* input stream */
private:
int getcode(int bits, int abfin);
- int dgif(IMAGEN *img, int interl, int bits);
+ int dgif(GIFImage *img, int interl, int bits);
public:
- // constructor, destructor, etc.
- wxGIFDecoder(wxInputStream *s, bool anim = FALSE);
- ~wxGIFDecoder();
- bool CanRead();
- int ReadGIF();
- void Destroy();
-
- // convert current frame to wxImage
- bool ConvertToImage(wxImage *image) const;
-
// get data of current frame
int GetFrameIndex() const;
unsigned char* GetData() const;
// move through the animation
bool GoFirstFrame();
bool GoLastFrame();
- bool GoNextFrame(bool cyclic = FALSE);
- bool GoPrevFrame(bool cyclic = FALSE);
+ bool GoNextFrame(bool cyclic = false);
+ bool GoPrevFrame(bool cyclic = false);
bool GoFrame(int which);
+
+public:
+ // constructor, destructor, etc.
+ wxGIFDecoder(wxInputStream *s, bool anim = false);
+ ~wxGIFDecoder();
+ bool CanRead();
+ int ReadGIF();
+ void Destroy();
+
+ // convert current frame to wxImage
+ bool ConvertToImage(wxImage *image) const;
+
+ DECLARE_NO_COPY_CLASS(wxGIFDecoder)
};
-#endif // wxUSE_STREAM
+#endif // wxUSE_STREAM && wxUSE_GIF
#endif // _WX_GIFDECOD_H
projects / wxWidgets.git / blobdiff