/////////////////////////////////////////////////////////////////////////////
-// Name: gifdecod.h
+// Name: wx/gifdecod.h
// Purpose: wxGIFDecoder, GIF reader for wxImage and wxAnimation
// Author: Guillermo Rodriguez Garcia <guille@iies.es>
// Version: 3.02
// Licence: wxWindows licence
/////////////////////////////////////////////////////////////////////////////
-#ifndef _WX_GIFDECOD_H
-#define _WX_GIFDECOD_H
+#ifndef _WX_GIFDECOD_H_
+#define _WX_GIFDECOD_H_
-#ifdef __GNUG__
-#pragma interface "gifdecod.h"
-#endif
-
-#include "wx/setup.h"
+#include "wx/defs.h"
#if wxUSE_STREAMS && wxUSE_GIF
#include "wx/stream.h"
#include "wx/image.h"
+#include "wx/animdecod.h"
+#include "wx/dynarray.h"
+
+// internal utility used to store a frame in 8bit-per-pixel format
+class GIFImage;
// --------------------------------------------------------------------------
-// constants
+// Constants
// --------------------------------------------------------------------------
-// disposal method
-enum
+// 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.
+//
+enum wxGIFErrorCode
{
- 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 */
+ wxGIF_OK = 0, // everything was OK
+ wxGIF_INVFORMAT, // error in GIF header
+ wxGIF_MEMERR, // error allocating memory
+ wxGIF_TRUNCATED // file appears to be truncated
};
-// error codes
-enum
-{
- wxGIF_OK = 0, /* everything was OK */
- wxGIF_INVFORMAT = 1, /* error in gif header */
- wxGIF_MEMERR = 2 /* error allocating memory */
-};
-
-#define MAX_BLOCK_SIZE 256 /* max. block size */
-
-
// --------------------------------------------------------------------------
// wxGIFDecoder class
// --------------------------------------------------------------------------
-// internal class for storing GIF image data
-class GIFImage
+class WXDLLIMPEXP_CORE wxGIFDecoder : public wxAnimationDecoder
{
public:
- unsigned int w; /* width */
- unsigned int h; /* height */
- unsigned int left; /* x coord (in logical screen) */
- unsigned int top; /* y coord (in logical screen) */
- int transparent; /* transparent color (-1 = none) */
- int disposal; /* disposal method (-1 = unspecified) */
- long delay; /* delay in ms (-1 = unused) */
- unsigned char *p; /* bitmap */
- unsigned char *pal; /* palette */
- GIFImage *next; /* next image */
- GIFImage *prev; /* prev image */
-};
+ // constructor, destructor, etc.
+ wxGIFDecoder();
+ ~wxGIFDecoder();
+ // get data of current frame
+ unsigned char* GetData(unsigned int frame) const;
+ unsigned char* GetPalette(unsigned int frame) const;
+ unsigned int GetNcolours(unsigned int frame) const;
+ int GetTransparentColourIndex(unsigned int frame) const;
+ wxColour GetTransparentColour(unsigned int frame) const;
-class WXDLLEXPORT wxGIFDecoder
-{
-private:
- // 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
- bool m_anim; /* animated GIF */
- int m_nimages; /* number of images */
- int m_image; /* current image */
- GIFImage *m_pimage; /* pointer to current image */
- GIFImage *m_pfirst; /* pointer to first image */
- GIFImage *m_plast; /* pointer to last image */
+ virtual wxSize GetFrameSize(unsigned int frame) const;
+ virtual wxPoint GetFramePosition(unsigned int frame) const;
+ virtual wxAnimationDisposal GetDisposalMethod(unsigned int frame) const;
+ virtual long GetDelay(unsigned int frame) const;
- // 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 */
+ // GIFs can contain both static images and animations
+ bool IsAnimation() const
+ { return m_nFrames > 1; }
- // input stream
- wxInputStream *m_f; /* input stream */
+ // load function which returns more info than just Load():
+ wxGIFErrorCode LoadGIF( wxInputStream& stream );
+
+ // free all internal frames
+ void Destroy();
+
+ // implementation of wxAnimationDecoder's pure virtuals
+ virtual bool Load( wxInputStream& stream )
+ { return LoadGIF(stream) == wxGIF_OK; }
+
+ bool ConvertToImage(unsigned int frame, wxImage *image) const;
+
+ wxAnimationDecoder *Clone() const
+ { return new wxGIFDecoder; }
+ wxAnimationType GetType() const
+ { return wxANIMATION_TYPE_GIF; }
private:
- int getcode(int bits, int abfin);
- int dgif(GIFImage *img, int interl, int bits);
+ // wxAnimationDecoder pure virtual
+ virtual bool DoCanRead( wxInputStream& stream ) const;
+ // modifies current stream position (see wxAnimationDecoder::CanRead)
-protected:
- // get data of current frame
- int GetFrameIndex() const;
- unsigned char* GetData() const;
- unsigned char* GetPalette() const;
- unsigned int GetWidth() const;
- unsigned int GetHeight() const;
- unsigned int GetLeft() const;
- unsigned int GetTop() const;
- int GetDisposalMethod() const;
- int GetTransparentColour() const;
- long GetDelay() const;
-
- // get global data
- unsigned int GetLogicalScreenWidth() const;
- unsigned int GetLogicalScreenHeight() const;
- int GetBackgroundColour() const;
- int GetNumberOfFrames() const;
- bool IsAnimation() const;
-
- // move through the animation
- bool GoFirstFrame();
- bool GoLastFrame();
- bool GoNextFrame(bool cyclic = FALSE);
- bool GoPrevFrame(bool cyclic = FALSE);
- bool GoFrame(int which);
+ int getcode(wxInputStream& stream, int bits, int abfin);
+ wxGIFErrorCode dgif(wxInputStream& stream,
+ GIFImage *img, int interl, int bits);
-public:
- // constructor, destructor, etc.
- wxGIFDecoder(wxInputStream *s, bool anim = FALSE);
- ~wxGIFDecoder();
- bool CanRead();
- int ReadGIF();
- void Destroy();
+
+ // array of all frames
+ wxArrayPtrVoid m_frames;
- // convert current frame to wxImage
- bool ConvertToImage(wxImage *image) const;
-};
+ // 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[256]; // buffer for reading
+ unsigned char *m_bufp; // pointer to next byte in buffer
+ wxDECLARE_NO_COPY_CLASS(wxGIFDecoder);
+};
-#endif // wxUSE_STREAM && wxUSE_GIF
-#endif // _WX_GIFDECOD_H
+#endif // wxUSE_STREAMS && wxUSE_GIF
+#endif // _WX_GIFDECOD_H_
projects / wxWidgets.git / blobdiff