include/wx/msw/dib.h

   1 /////////////////////////////////////////////////////////////////////////////
   2 // Name:        wx/msw/dib.h
   3 // Purpose:     wxDIB class representing Win32 device independent bitmaps
   4 // Author:      Vadim Zeitlin
   5 // Modified by:
   6 // Created:     03.03.03 (replaces the old file with the same name)
   7 // RCS-ID:      $Id$
   8 // Copyright:   (c) 1997-2003 wxWindows team
   9 // Licence:     wxWindows licence
  10 /////////////////////////////////////////////////////////////////////////////
  11
  12 #ifndef _WX_MSW_DIB_H_
  13 #define _WX_MSW_DIB_H_
  14
  15 class WXDLLEXPORT wxBitmap;
  16 class WXDLLEXPORT wxPalette;
  17
  18 #include "wx/msw/private.h"
  19
  20 // ----------------------------------------------------------------------------
  21 // wxDIB: represents a DIB section
  22 // ----------------------------------------------------------------------------
  23
  24 class WXDLLEXPORT wxDIB
  25 {
  26 public:
  27     // ctors and such
  28     // --------------
  29
  30     // create an uninitialized DIB with the given width, height and depth (only
  31     // 24 and 32 bpp DIBs are currently supported)
  32     //
  33     // after using this ctor, GetData() and GetHandle() may be used if IsOk()
  34     // returns true
  35     wxDIB(int width, int height, int depth)
  36         { Init(); (void)Create(width, height, depth); }
  37
  38     // same as ctor but with return value
  39     bool Create(int width, int height, int depth);
  40
  41     // dtor is not virtual, this class is not meant to be used polymorphically
  42     ~wxDIB()
  43     {
  44         if ( m_handle && !::DeleteObject(m_handle) )
  45         {
  46             wxLogLastError(wxT("DeleteObject(hDIB)"));
  47         }
  48     }
  49
  50
  51     // operations
  52     // ----------
  53
  54     // get the handle from the DIB and reset it, i.e. this object won't destroy
  55     // the DIB after this (but the caller should do it)
  56     HBITMAP Detach() { HBITMAP hbmp = m_handle; m_handle = 0; return hbmp; }
  57
  58
  59     // accessors
  60     // ---------
  61
  62     // return true if DIB was successfully created, false otherwise
  63     bool IsOk() const { return m_handle != 0; }
  64
  65     // get the bitmap size
  66     wxSize GetSize() const { DoGetObject(); return wxSize(m_width, m_height); }
  67     int GetWidth() const { DoGetObject(); return m_width; }
  68     int GetHeight() const { DoGetObject(); return m_height; }
  69
  70     // get the number of bits per pixel, or depth
  71     int GetDepth() const { DoGetObject(); return m_depth; }
  72
  73     // get the DIB handle
  74     HBITMAP GetHandle() const { return m_handle; }
  75
  76     // get raw pointer to bitmap bits, you should know what you do if you
  77     // decide to use it
  78     void *GetData() const { DoGetObject(); return m_data; }
  79
  80
  81     // wxImage conversion
  82     // ------------------
  83
  84 #if wxUSE_IMAGE
  85     // create a DIB from the given image, the DIB will be either 24 or 32 (if
  86     // the image has alpha channel) bpp
  87     wxDIB(const wxImage& image) { Init(); (void)Create(image); }
  88
  89     // same as the above ctor but with the return code
  90     bool Create(const wxImage& image);
  91
  92     // create wxImage having the same data as this DIB
  93     wxImage ConvertToImage() const;
  94 #endif // wxUSE_IMAGE
  95
  96
  97     // helper functions
  98     // ----------------
  99
 100     // return the size of one line in a DIB with given width and depth: the
 101     // point here is that as the scan lines need to be DWORD aligned so we may
 102     // need to add some padding
 103     static unsigned long GetLineSize(int width, int depth)
 104     {
 105         return ((width*depth + 31) & ~31) >> 3;
 106     }
 107
 108 private:
 109     // common part of all ctors
 110     void Init()
 111     {
 112         m_handle = 0;
 113
 114         m_data = NULL;
 115
 116         m_width =
 117         m_height =
 118         m_depth = 0;
 119     }
 120
 121     // the DIB section handle, 0 if invalid
 122     HBITMAP m_handle;
 123
 124     // NB: we could store only m_handle and not any of the other fields as
 125     //     we may always retrieve them from it using ::GetObject(), but we
 126     //     decide to still store them for efficiency concerns -- however if we
 127     //     don't have them from the very beginning (e.g. DIB constructed from a
 128     //     bitmap), we only retrieve them when necessary and so these fields
 129     //     should *never* be accessed directly, even from inside wxDIB code
 130
 131     // function which must be called before accessing any members and which
 132     // gets their values from m_handle, if not done yet
 133     void DoGetObject() const;
 134
 135     // pointer to DIB bits, may be NULL
 136     void *m_data;
 137
 138     // size and depth of the image
 139     int m_width,
 140         m_height,
 141         m_depth;
 142
 143
 144     // DIBs can't be copied
 145     wxDIB(const wxDIB&);
 146     wxDIB& operator=(const wxDIB&);
 147 };
 148
 149
 150 // ----------------------------------------------------------------------------
 151 // Functions for working with DIBs
 152 // ----------------------------------------------------------------------------
 153
 154 // WARNING: these functions are private to wxWindows and shouldn't be used
 155 //          by the user code, they risk to disappear in the next versions!
 156
 157 // VZ: we have 3 different sets of functions: from bitmap.cpp (wxCreateDIB and
 158 //     wxFreeDIB), from dib.cpp and from dataobj.cpp - surely there is some
 159 //     redundancy between them? (FIXME)
 160
 161 // defined in bitmap.cpp
 162 extern bool wxCreateDIB(long xSize, long ySize, long bitsPerPixel,
 163                        HPALETTE hPal, LPBITMAPINFO* lpDIBHeader);
 164 extern void wxFreeDIB(LPBITMAPINFO lpDIBHeader);
 165
 166 // defined in ole/dataobj.cpp
 167 extern WXDLLEXPORT size_t wxConvertBitmapToDIB(LPBITMAPINFO pbi, const wxBitmap& bitmap);
 168 extern WXDLLEXPORT wxBitmap wxConvertDIBToBitmap(const LPBITMAPINFO pbi);
 169
 170 // the rest is defined in dib.cpp
 171
 172 // Save (device dependent) wxBitmap as a DIB
 173 bool wxSaveBitmap(wxChar *filename, wxBitmap *bitmap, wxPalette *colourmap = NULL);
 174
 175 // Load device independent bitmap into device dependent bitmap
 176 wxBitmap *wxLoadBitmap(wxChar *filename, wxPalette **colourmap = NULL);
 177
 178 // Load into existing bitmap;
 179 bool wxLoadIntoBitmap(wxChar *filename, wxBitmap *bitmap, wxPalette **pal = NULL);
 180
 181 HANDLE wxBitmapToDIB (HBITMAP hBitmap, HPALETTE hPal);
 182 BOOL   wxReadDIB(LPTSTR lpFileName, HBITMAP *bitmap, HPALETTE *palette);
 183 HANDLE wxReadDIB2(LPTSTR lpFileName);
 184 LPSTR wxFindDIBBits (LPSTR lpbi);
 185 HPALETTE wxMakeDIBPalette(LPBITMAPINFOHEADER lpInfo);
 186
 187 #endif // _WX_MSW_DIB_H_
 188