| 1 | ///////////////////////////////////////////////////////////////////////////// |
| 2 | // Name: wx/animdecod.h |
| 3 | // Purpose: wxAnimationDecoder |
| 4 | // Author: Francesco Montorsi |
| 5 | // CVS-ID: $Id$ |
| 6 | // Copyright: (c) 2006 Francesco Montorsi |
| 7 | // Licence: wxWindows licence |
| 8 | ///////////////////////////////////////////////////////////////////////////// |
| 9 | |
| 10 | #ifndef _WX_ANIMDECOD_H |
| 11 | #define _WX_ANIMDECOD_H |
| 12 | |
| 13 | #include "wx/defs.h" |
| 14 | |
| 15 | #if wxUSE_STREAMS |
| 16 | |
| 17 | #include "wx/colour.h" |
| 18 | #include "wx/gdicmn.h" |
| 19 | |
| 20 | class WXDLLIMPEXP_FWD_BASE wxInputStream; |
| 21 | class WXDLLIMPEXP_FWD_CORE wxImage; |
| 22 | |
| 23 | /* |
| 24 | |
| 25 | Differences between a wxAnimationDecoder and a wxImageHandler: |
| 26 | |
| 27 | 1) wxImageHandlers always load an input stream directly into a given wxImage |
| 28 | object converting from the format-specific data representation to the |
| 29 | wxImage native format (RGB24). |
| 30 | wxAnimationDecoders always load an input stream using some optimized format |
| 31 | to store it which is format-depedent. This allows to store a (possibly big) |
| 32 | animation using a format which is a good compromise between required memory |
| 33 | and time required to blit in on the screen. |
| 34 | |
| 35 | 2) wxAnimationDecoders contain the animation data in some internal var. |
| 36 | That's why they derive from wxObjectRefData: they are data which can be shared. |
| 37 | |
| 38 | 3) wxAnimationDecoders can be used by a wxImageHandler to retrieve a frame |
| 39 | in wxImage format; the viceversa cannot be done. |
| 40 | |
| 41 | 4) wxAnimationDecoders are decoders only, thus do not support save features. |
| 42 | |
| 43 | 5) wxAnimationDecoders are directly used by wxAnimation (generic implementation) |
| 44 | as wxObjectRefData while they need to be 'wrapped' by a wxImageHandler for |
| 45 | wxImage uses. |
| 46 | |
| 47 | */ |
| 48 | |
| 49 | |
| 50 | // -------------------------------------------------------------------------- |
| 51 | // Constants |
| 52 | // -------------------------------------------------------------------------- |
| 53 | |
| 54 | // NB: the values of these enum items are not casual but coincide with the |
| 55 | // GIF disposal codes. Do not change them !! |
| 56 | enum wxAnimationDisposal |
| 57 | { |
| 58 | // No disposal specified. The decoder is not required to take any action. |
| 59 | wxANIM_UNSPECIFIED = -1, |
| 60 | |
| 61 | // Do not dispose. The graphic is to be left in place. |
| 62 | wxANIM_DONOTREMOVE = 0, |
| 63 | |
| 64 | // Restore to background color. The area used by the graphic must be |
| 65 | // restored to the background color. |
| 66 | wxANIM_TOBACKGROUND = 1, |
| 67 | |
| 68 | // Restore to previous. The decoder is required to restore the area |
| 69 | // overwritten by the graphic with what was there prior to rendering the graphic. |
| 70 | wxANIM_TOPREVIOUS = 2 |
| 71 | }; |
| 72 | |
| 73 | enum wxAnimationType |
| 74 | { |
| 75 | wxANIMATION_TYPE_INVALID, |
| 76 | wxANIMATION_TYPE_GIF, |
| 77 | wxANIMATION_TYPE_ANI, |
| 78 | |
| 79 | wxANIMATION_TYPE_ANY |
| 80 | }; |
| 81 | |
| 82 | |
| 83 | // -------------------------------------------------------------------------- |
| 84 | // wxAnimationDecoder class |
| 85 | // -------------------------------------------------------------------------- |
| 86 | |
| 87 | class WXDLLIMPEXP_CORE wxAnimationDecoder : public wxObjectRefData |
| 88 | { |
| 89 | public: |
| 90 | wxAnimationDecoder() |
| 91 | { |
| 92 | m_nFrames = 0; |
| 93 | } |
| 94 | |
| 95 | virtual bool Load( wxInputStream& stream ) = 0; |
| 96 | virtual bool CanRead( wxInputStream& stream ) const = 0; |
| 97 | |
| 98 | virtual wxAnimationDecoder *Clone() const = 0; |
| 99 | virtual wxAnimationType GetType() const = 0; |
| 100 | |
| 101 | // convert given frame to wxImage |
| 102 | virtual bool ConvertToImage(unsigned int frame, wxImage *image) const = 0; |
| 103 | |
| 104 | |
| 105 | // frame specific data getters |
| 106 | |
| 107 | // not all frames may be of the same size; e.g. GIF allows to |
| 108 | // specify that between two frames only a smaller portion of the |
| 109 | // entire animation has changed. |
| 110 | virtual wxSize GetFrameSize(unsigned int frame) const = 0; |
| 111 | |
| 112 | // the position of this frame in case it's not as big as m_szAnimation |
| 113 | // or wxPoint(0,0) otherwise. |
| 114 | virtual wxPoint GetFramePosition(unsigned int frame) const = 0; |
| 115 | |
| 116 | // what should be done after displaying this frame. |
| 117 | virtual wxAnimationDisposal GetDisposalMethod(unsigned int frame) const = 0; |
| 118 | |
| 119 | // the number of milliseconds this frame should be displayed. |
| 120 | // if returns -1 then the frame must be displayed forever. |
| 121 | virtual long GetDelay(unsigned int frame) const = 0; |
| 122 | |
| 123 | // the transparent colour for this frame if any or wxNullColour. |
| 124 | virtual wxColour GetTransparentColour(unsigned int frame) const = 0; |
| 125 | |
| 126 | // get global data |
| 127 | wxSize GetAnimationSize() const { return m_szAnimation; } |
| 128 | wxColour GetBackgroundColour() const { return m_background; } |
| 129 | unsigned int GetFrameCount() const { return m_nFrames; } |
| 130 | |
| 131 | protected: |
| 132 | wxSize m_szAnimation; |
| 133 | unsigned int m_nFrames; |
| 134 | |
| 135 | // this is the colour to use for the wxANIM_TOBACKGROUND disposal. |
| 136 | // if not specified by the animation, it's set to wxNullColour |
| 137 | wxColour m_background; |
| 138 | }; |
| 139 | |
| 140 | #endif // wxUSE_STREAMS |
| 141 | |
| 142 | #endif // _WX_ANIMDECOD_H |
| 143 | |