X-Git-Url: https://git.saurik.com/wxWidgets.git/blobdiff_plain/1cfa5d8e39c6572fd20438d5bc29360a56ac328b..96c9640205933ad0673d5af2c96af0816c50160c:/src/msw/dib.cpp diff --git a/src/msw/dib.cpp b/src/msw/dib.cpp index f5abc79777..00faac6a4e 100644 --- a/src/msw/dib.cpp +++ b/src/msw/dib.cpp @@ -6,9 +6,15 @@ // Created: 03.03.03 (replaces the old file with the same name) // RCS-ID: $Id$ // Copyright: (c) 2003 Vadim Zeitlin -// License: wxWindows licence +// Licence: wxWindows licence /////////////////////////////////////////////////////////////////////////////// +/* + TODO: support for palettes is very incomplete, several functions simply + ignore them (we should select and realize the palette, if any, before + caling GetDIBits() in the DC we use with it. + */ + // ============================================================================ // declarations // ============================================================================ @@ -24,27 +30,52 @@ #pragma hdrstop #endif +#if wxUSE_WXDIB + #ifndef WX_PRECOMP #include "wx/string.h" #include "wx/log.h" + #include "wx/intl.h" + #include "wx/bitmap.h" + #include "wx/image.h" #endif //WX_PRECOMP -#include "wx/bitmap.h" -#include "wx/intl.h" +#include "wx/file.h" #include #include -#if !defined(__MWERKS__) && !defined(__SALFORDC__) #include -#endif -#ifdef __GNUWIN32_OLD__ - #include "wx/msw/gnuwin32/extra.h" +#include "wx/msw/dib.h" + +#ifdef __WXWINCE__ + #include // for SHLoadDIBitmap() #endif -#include "wx/image.h" -#include "wx/msw/dib.h" +// ---------------------------------------------------------------------------- +// private functions +// ---------------------------------------------------------------------------- + +// calculate the number of palette entries needed for the bitmap with this +// number of bits per pixel +static inline WORD GetNumberOfColours(WORD bitsPerPixel) +{ + // only 1, 4 and 8bpp bitmaps use palettes (well, they could be used with + // 24bpp ones too but we don't support this as I think it's quite uncommon) + return (WORD)(bitsPerPixel <= 8 ? 1 << bitsPerPixel : 0); +} + +// wrapper around ::GetObject() for DIB sections +static inline bool GetDIBSection(HBITMAP hbmp, DIBSECTION *ds) +{ + // note that at least under Win9x (this doesn't seem to happen under Win2K + // but this doesn't mean anything, of course), GetObject() may return + // sizeof(DIBSECTION) for a bitmap which is *not* a DIB section and the way + // to check for it is by looking at the bits pointer + return ::GetObject(hbmp, sizeof(DIBSECTION), ds) == sizeof(DIBSECTION) && + ds->dsBm.bmBits; +} // ============================================================================ // implementation @@ -56,39 +87,40 @@ bool wxDIB::Create(int width, int height, int depth) { - // we don't handle the palette yet - wxASSERT_MSG( depth == 24 || depth == 32, - _T("unsupported image depth in wxDIB::Create()") ); - - static const int infosize = sizeof(BITMAPINFOHEADER); + // we don't support formats using palettes right now so we only create + // either 24bpp (RGB) or 32bpp (RGBA) bitmaps + wxASSERT_MSG( depth, wxT("invalid image depth in wxDIB::Create()") ); + if ( depth < 24 ) + depth = 24; + + // allocate memory for bitmap structures + BITMAPINFO info; + wxZeroMemory(info); + + info.bmiHeader.biSize = sizeof(BITMAPINFOHEADER); + info.bmiHeader.biWidth = width; + + // we use positive height here which corresponds to a DIB with normal, i.e. + // bottom to top, order -- normally using negative height (which means + // reversed for MS and hence natural for all the normal people top to + // bottom line scan order) could be used to avoid the need for the image + // reversal in Create(image) but this doesn't work under NT, only Win9x! + info.bmiHeader.biHeight = height; + + info.bmiHeader.biPlanes = 1; + info.bmiHeader.biBitCount = (WORD)depth; + info.bmiHeader.biSizeImage = GetLineSize(width, depth)*height; - BITMAPINFO *info = (BITMAPINFO *)malloc(infosize); - wxCHECK_MSG( info, NULL, _T("malloc(BITMAPINFO) failed") ); - - memset(info, 0, infosize); - - info->bmiHeader.biSize = infosize; - info->bmiHeader.biWidth = width; - info->bmiHeader.biHeight = -height; - info->bmiHeader.biPlanes = 1; - info->bmiHeader.biBitCount = depth; - info->bmiHeader.biCompression = BI_RGB; - info->bmiHeader.biSizeImage = GetLineSize(width, depth)*height; - - // No need to report an error here. If it fails, we just won't use a - // file mapping and CreateDIBSection will just allocate memory for us. m_handle = ::CreateDIBSection ( 0, // hdc (unused with DIB_RGB_COLORS) - info, // bitmap description + &info, // bitmap description DIB_RGB_COLORS, // use RGB, not palette &m_data, // [out] DIB bits NULL, // don't use file mapping 0 // file mapping offset (not used here) ); - free(info); - if ( !m_handle ) { wxLogLastError(wxT("CreateDIBSection")); @@ -103,795 +135,719 @@ bool wxDIB::Create(int width, int height, int depth) return true; } -// ---------------------------------------------------------------------------- -// wxDIB accessors -// ---------------------------------------------------------------------------- - -void wxDIB::DoGetObject() const +bool wxDIB::Create(HBITMAP hbmp) { - // only do something if we have a valid DIB but we don't [yet] have valid - // data - if ( m_handle && !m_data ) + wxCHECK_MSG( hbmp, false, wxT("wxDIB::Create(): invalid bitmap") ); + + // this bitmap could already be a DIB section in which case we don't need + // to convert it to DIB + DIBSECTION ds; + if ( GetDIBSection(hbmp, &ds) ) { - // although all the info we need is in BITMAP and so we don't really - // need DIBSECTION we still ask for it as modifying the bit values only - // works for the real DIBs and not for the bitmaps and it's better to - // check for this now rather than trying to find out why it doesn't - // work later - DIBSECTION ds; - if ( !::GetObject(m_handle, sizeof(ds), &ds) ) + m_handle = hbmp; + + // wxBitmap will free it, not we + m_ownsHandle = false; + + // copy all the bitmap parameters too as we have them now anyhow + m_width = ds.dsBm.bmWidth; + m_height = ds.dsBm.bmHeight; + m_depth = ds.dsBm.bmBitsPixel; + + m_data = ds.dsBm.bmBits; + } + else // no, it's a DDB -- convert it to DIB + { + // prepare all the info we need + BITMAP bm; + if ( !::GetObject(hbmp, sizeof(bm), &bm) ) { - wxLogLastError(_T("GetObject(hDIB)")); + wxLogLastError(wxT("GetObject(bitmap)")); - return; + return false; } - wxDIB *self = wxConstCast(this, wxDIB); + int d = bm.bmBitsPixel; + if ( d <= 0 ) + d = wxDisplayDepth(); - self->m_width = ds.dsBm.bmWidth; - self->m_height = ds.dsBm.bmHeight; - self->m_depth = ds.dsBm.bmBitsPixel; - self->m_data = ds.dsBm.bmBits; + if ( !Create(bm.bmWidth, bm.bmHeight, d) || !CopyFromDDB(hbmp) ) + return false; } -} -// ---------------------------------------------------------------------------- -// wxImage support -// ---------------------------------------------------------------------------- + return true; +} -#if wxUSE_IMAGE +// Windows CE doesn't have GetDIBits() so use an alternative implementation +// for it +// +// in fact I'm not sure if GetDIBits() is really much better than using +// BitBlt() like this -- it should be faster but I didn't do any tests, if +// anybody has time to do them and by chance finds that GetDIBits() is not +// much faster than BitBlt(), we could always use the Win CE version here +#ifdef __WXWINCE__ -bool wxDIB::Create(const wxImage& image) +bool wxDIB::CopyFromDDB(HBITMAP hbmp) { - wxCHECK_MSG( image.Ok(), false, _T("invalid wxImage in wxDIB ctor") ); - - const int h = image.GetHeight(); - const int w = image.GetWidth(); - - // if we have alpha channel, we need to create a 32bpp RGBA DIB, otherwise - // a 24bpp RGB is sufficient - const bool hasAlpha = image.HasAlpha(); - const int bpp = hasAlpha ? 32 : 24; + MemoryHDC hdcSrc; + if ( !hdcSrc ) + return false; - if ( !Create(w, h, bpp) ) + SelectInHDC selectSrc(hdcSrc, hbmp); + if ( !selectSrc ) return false; - // DIBs are stored in bottom to top order so we need to copy bits line by - // line and starting from the end - const int srcBytesPerLine = w * 3; - const int dstBytesPerLine = GetLineSize(w, bpp); - const unsigned char *src = image.GetData() + ((h - 1) * srcBytesPerLine); - const unsigned char *alpha = hasAlpha ? image.GetAlpha() + (h - 1)*w : NULL; - unsigned char *dstLineStart = (unsigned char *)m_data; - for ( int y = 0; y < h; y++ ) - { - // copy one DIB line - unsigned char *dst = dstLineStart; - for ( int x = 0; x < w; x++ ) - { - // also, the order of RGB is inversed for DIBs - *dst++ = src[2]; - *dst++ = src[1]; - *dst++ = src[0]; + MemoryHDC hdcDst; + if ( !hdcDst ) + return false; - src += 3; + SelectInHDC selectDst(hdcDst, m_handle); + if ( !selectDst ) + return false; - if ( alpha ) - *dst++ = *alpha++; - } - // pass to the previous line in the image - src -= 2*srcBytesPerLine; - if ( alpha ) - alpha -= 2*w; + if ( !::BitBlt( + hdcDst, + 0, 0, m_width, m_height, + hdcSrc, + 0, 0, + SRCCOPY + ) ) + { + wxLogLastError(wxT("BitBlt(DDB -> DIB)")); - // and to the next one in the DIB - dstLineStart += dstBytesPerLine; + return false; } return true; } -#endif // wxUSE_IMAGE - -// ============================================================================ -// old DIB code, to be integrated in wxDIB class -// ============================================================================ +#else // !__WXWINCE__ -/* - * Routines for dealing with Device Independent Bitmaps. - * - * wxReadDIB() - Reads a DIB - * wxWriteDIB() - Writes a global handle in CF_DIB format - * to a file. - * wxPaletteSize() - Calculates the palette size in bytes - * of given DIB - * wxDibNumColors() - Determines the number of colors in DIB - * wxDibFromBitmap() - Creates a DIB repr. the DDB passed in. - * lread() - Private routine to read more than 64k - * lwrite() - Private routine to write more than 64k - */ +bool wxDIB::CopyFromDDB(HBITMAP hbmp) +{ + DIBSECTION ds; + if ( !GetDIBSection(m_handle, &ds) ) + { + // we're sure that our handle is a DIB section, so this should work + wxFAIL_MSG( wxT("GetObject(DIBSECTION) unexpectedly failed") ); -#ifndef SEEK_CUR -/* flags for _lseek */ -#define SEEK_CUR 1 -#define SEEK_END 2 -#define SEEK_SET 0 -#endif + return false; + } -#define MAXREAD 32768 /* Number of bytes to be read during */ - /* each read operation. */ + if ( !::GetDIBits + ( + ScreenHDC(), // the DC to use + hbmp, // the source DDB + 0, // first scan line + m_height, // number of lines to copy + ds.dsBm.bmBits, // pointer to the buffer + (BITMAPINFO *)&ds.dsBmih, // bitmap header + DIB_RGB_COLORS // and not DIB_PAL_COLORS + ) ) + { + wxLogLastError(wxT("GetDIBits()")); -/* Header signatutes for various resources */ -#define BFT_ICON 0x4349 /* 'IC' */ -#define BFT_BITMAP 0x4d42 /* 'BM' */ -#define BFT_CURSOR 0x5450 /* 'PT(' */ + return false; + } -/* macro to determine if resource is a DIB */ -#define ISDIB(bft) ((bft) == BFT_BITMAP) + return true; +} -/* Macro to align given value to the closest DWORD (unsigned long ) */ -#define ALIGNULONG(i) ((i+3)/4*4) +#endif // __WXWINCE__/!__WXWINCE__ -/* Macro to determine to round off the given value to the closest byte */ -#define WIDTHBYTES(i) ((i+31)/32*4) +// ---------------------------------------------------------------------------- +// Loading/saving the DIBs +// ---------------------------------------------------------------------------- -#define PALVERSION 0x300 -#define MAXPALETTE 256 /* max. # supported palette entries */ +bool wxDIB::Load(const wxString& filename) +{ +#ifdef __WXWINCE__ + m_handle = SHLoadDIBitmap(filename); +#else // !__WXWINCE__ + m_handle = (HBITMAP)::LoadImage + ( + wxGetInstance(), + filename.t_str(), + IMAGE_BITMAP, + 0, 0, // don't specify the size + LR_CREATEDIBSECTION | LR_LOADFROMFILE + ); +#endif // __WXWINCE__ -static DWORD lread(int fh, VOID FAR *pv, DWORD ul); -static DWORD lwrite(int fh, VOID FAR *pv, DWORD ul); + if ( !m_handle ) + { + wxLogLastError(wxT("Loading DIB from file")); -static bool wxWriteDIB (LPTSTR szFile,HANDLE hdib); -WORD wxPaletteSize (VOID FAR * pv); // This is non-static as some apps use it externally -static WORD wxDibNumColors (VOID FAR * pv); -static bool wxMakeBitmapAndPalette(HDC,HANDLE,HPALETTE *,HBITMAP *); + return false; + } -/* - * FUNCTION : wxWriteDIB(LPSTR szFile,HANDLE hdib) - * PURPOSE : Write a global handle in CF_DIB format to a file. - * RETURNS : TRUE - if successful. - * FALSE - otherwise - */ + return true; +} -static bool wxWriteDIB(LPTSTR szFile, HANDLE hdib) +bool wxDIB::Save(const wxString& filename) { - BITMAPFILEHEADER hdr; - LPBITMAPINFOHEADER lpbi; - int fh; - OFSTRUCT of; - - if (!hdib) - return FALSE; - - fh = OpenFile(wxConvertWX2MB(szFile), &of, OF_CREATE | OF_READWRITE); - if (fh == -1) - return FALSE; - - lpbi = (LPBITMAPINFOHEADER) GlobalLock(hdib); - - /* Fill in the fields of the file header */ - hdr.bfType = BFT_BITMAP; - hdr.bfSize = GlobalSize(hdib) + sizeof(BITMAPFILEHEADER); - hdr.bfReserved1 = 0; - hdr.bfReserved2 = 0; - hdr.bfOffBits = (DWORD) sizeof(BITMAPFILEHEADER) + lpbi->biSize + - wxPaletteSize(lpbi); - - /* Write the file header */ - _lwrite(fh, (LPSTR) &hdr, sizeof(BITMAPFILEHEADER)); - - /* Write the DIB header and the bits */ - lwrite(fh, (LPSTR) lpbi, GlobalSize(hdib)); - - GlobalUnlock(hdib); - _lclose(fh); - return TRUE; -} + wxCHECK_MSG( m_handle, false, wxT("wxDIB::Save(): invalid object") ); -/* - * FUNCTION : wxPaletteSize(VOID FAR * pv) - * PURPOSE : Calculates the palette size in bytes. If the info. block - * is of the BITMAPCOREHEADER type, the number of colors is - * multiplied by 3 to give the palette size, otherwise the - * number of colors is multiplied by 4. - * RETURNS : Palette size in number of bytes. - */ +#if wxUSE_FILE + wxFile file(filename, wxFile::write); + bool ok = file.IsOpened(); + if ( ok ) + { + DIBSECTION ds; + if ( !GetDIBSection(m_handle, &ds) ) + { + wxLogLastError(wxT("GetObject(hDIB)")); + } + else + { + BITMAPFILEHEADER bmpHdr; + wxZeroMemory(bmpHdr); -WORD wxPaletteSize(VOID FAR * pv) -{ - LPBITMAPINFOHEADER lpbi; - WORD NumColors; - - lpbi = (LPBITMAPINFOHEADER) pv; - NumColors = wxDibNumColors(lpbi); - - if (lpbi->biSize == sizeof(BITMAPCOREHEADER)) - return (WORD)(NumColors * sizeof(RGBTRIPLE)); - else - return (WORD)(NumColors * sizeof(RGBQUAD)); -} + const size_t sizeHdr = ds.dsBmih.biSize; + const size_t sizeImage = ds.dsBmih.biSizeImage; -/* - * FUNCTION : wxDibNumColors(VOID FAR * pv) - * PURPOSE : Determines the number of colors in the DIB by looking at - * the BitCount filed in the info block. - * RETURNS : The number of colors in the DIB. * - */ + bmpHdr.bfType = 0x4d42; // 'BM' in little endian + bmpHdr.bfOffBits = sizeof(BITMAPFILEHEADER) + ds.dsBmih.biSize; + bmpHdr.bfSize = bmpHdr.bfOffBits + sizeImage; -static WORD wxDibNumColors(VOID FAR *pv) -{ - int bits; - BITMAPINFOHEADER *lpbi; - BITMAPCOREHEADER *lpbc; - - lpbi = ((BITMAPINFOHEADER*) pv); - lpbc = ((BITMAPCOREHEADER*) pv); - - /* With the BITMAPINFO format headers, the size of the palette - * is in biClrUsed, whereas in the BITMAPCORE - style headers, it - * is dependent on the bits per pixel ( = 2 raised to the power of - * bits/pixel). - */ - if (lpbi->biSize != sizeof(BITMAPCOREHEADER)) { - if (lpbi->biClrUsed != 0) - return (WORD) lpbi->biClrUsed; - bits = lpbi->biBitCount; + // first write the file header, then the bitmap header and finally the + // bitmap data itself + ok = file.Write(&bmpHdr, sizeof(bmpHdr)) == sizeof(bmpHdr) && + file.Write(&ds.dsBmih, sizeHdr) == sizeHdr && + file.Write(ds.dsBm.bmBits, sizeImage) == sizeImage; + } } - else - bits = lpbc->bcBitCount; - - switch (bits) { - case 1: - return 2; - case 4: - return 16; - case 8: - return 256; - default: - /* A 24 bitcount DIB has no color table */ - return 0; +#else // !wxUSE_FILE + bool ok = false; +#endif // wxUSE_FILE/!wxUSE_FILE + + if ( !ok ) + { + wxLogError(_("Failed to save the bitmap image to file \"%s\"."), + filename.c_str()); } + + return ok; } -/* - * FUNCTION : lread(int fh, VOID FAR *pv, DWORD ul) - * PURPOSE : Reads data in steps of 32k till all the data has been read. - * RETURNS : 0 - If read did not proceed correctly. - * number of bytes read otherwise. - */ +// ---------------------------------------------------------------------------- +// wxDIB accessors +// ---------------------------------------------------------------------------- -static DWORD lread(int fh, void far *pv, DWORD ul) +void wxDIB::DoGetObject() const { - DWORD ulT = ul; -#if defined(WINNT) || defined(__WIN32__) || defined(__WIN32__) - BYTE *hp = (BYTE *) pv; -#else - BYTE huge *hp = (BYTE huge *) pv; -#endif - while (ul > (DWORD) MAXREAD) { - if (_lread(fh, (LPSTR) hp, (WORD) MAXREAD) != MAXREAD) - return 0; - ul -= MAXREAD; - hp += MAXREAD; - } - if (_lread(fh, (LPSTR) hp, (WXUINT) ul) != (WXUINT) ul) - return 0; - return ulT; -} + // only do something if we have a valid DIB but we don't [yet] have valid + // data + if ( m_handle && !m_data ) + { + // although all the info we need is in BITMAP and so we don't really + // need DIBSECTION we still ask for it as modifying the bit values only + // works for the real DIBs and not for the bitmaps and it's better to + // check for this now rather than trying to find out why it doesn't + // work later + DIBSECTION ds; + if ( !GetDIBSection(m_handle, &ds) ) + { + wxLogLastError(wxT("GetObject(hDIB)")); + return; + } -/* - * FUNCTION : lwrite(int fh, VOID FAR *pv, DWORD ul) - * PURPOSE : Writes data in steps of 32k till all the data is written. - * RETURNS : 0 - If write did not proceed correctly. - * number of bytes written otherwise. - */ + wxDIB *self = wxConstCast(this, wxDIB); -static DWORD lwrite(int fh, VOID FAR *pv, DWORD ul) -{ - DWORD ulT = ul; -#if defined(WINNT) || defined(__WIN32__) || defined(__WIN32__) - BYTE *hp = (BYTE *) pv; -#else - BYTE huge *hp = (BYTE huge *) pv; -#endif - while (ul > MAXREAD) { - if (_lwrite(fh, (LPSTR) hp, (WORD) MAXREAD) != MAXREAD) - return 0; - ul -= MAXREAD; - hp += MAXREAD; + self->m_width = ds.dsBm.bmWidth; + self->m_height = ds.dsBm.bmHeight; + self->m_depth = ds.dsBm.bmBitsPixel; + self->m_data = ds.dsBm.bmBits; } - if (_lwrite(fh, (LPSTR) hp, (WXUINT) ul) != (WXUINT) ul) - return 0; - return ulT; } -/* - * FUNCTION : wxReadDIB(hWnd) - * PURPOSE : Reads a DIB from a file, obtains a handle to its - * BITMAPINFO struct. and loads the DIB. Once the DIB - * is loaded, the function also creates a bitmap and - * palette out of the DIB for a device-dependent form. - * RETURNS : TRUE - DIB loaded and bitmap/palette created - * The DIBINIT structure pointed to by pInfo is - * filled with the appropriate handles. - * FALSE - otherwise - */ - -bool wxReadDIB(LPTSTR lpFileName, HBITMAP *bitmap, HPALETTE *palette) +// ---------------------------------------------------------------------------- +// DDB <-> DIB conversions +// ---------------------------------------------------------------------------- + +#ifndef __WXWINCE__ + +HBITMAP wxDIB::CreateDDB(HDC hdc) const { - int fh; - LPBITMAPINFOHEADER lpbi; - OFSTRUCT of; - BITMAPFILEHEADER bf; - WORD nNumColors; - bool result = FALSE; - WORD offBits; - HDC hDC; - bool bCoreHead = FALSE; - HANDLE hDIB = 0; - - /* Open the file and get a handle to it's BITMAPINFO */ - - fh = OpenFile (wxConvertWX2MB(lpFileName), &of, OF_READ); - if (fh == -1) { - wxLogError(_("Can't open file '%s'"), lpFileName); - return (0); - } - - hDIB = GlobalAlloc(GHND, (DWORD)(sizeof(BITMAPINFOHEADER) + - 256 * sizeof(RGBQUAD))); - if (!hDIB) - return(0); - - lpbi = (LPBITMAPINFOHEADER)GlobalLock(hDIB); - - /* read the BITMAPFILEHEADER */ - if (sizeof (bf) != _lread (fh, (LPSTR)&bf, sizeof (bf))) - goto ErrExit; - - if (bf.bfType != 0x4d42) /* 'BM' */ - goto ErrExit; - - if (sizeof(BITMAPCOREHEADER) != _lread (fh, (LPSTR)lpbi, sizeof(BITMAPCOREHEADER))) - goto ErrExit; - - if (lpbi->biSize == sizeof(BITMAPCOREHEADER)) + wxCHECK_MSG( m_handle, 0, wxT("wxDIB::CreateDDB(): invalid object") ); + + DIBSECTION ds; + if ( !GetDIBSection(m_handle, &ds) ) { - lpbi->biSize = sizeof(BITMAPINFOHEADER); - lpbi->biBitCount = ((LPBITMAPCOREHEADER)lpbi)->bcBitCount; - lpbi->biPlanes = ((LPBITMAPCOREHEADER)lpbi)->bcPlanes; - lpbi->biHeight = ((LPBITMAPCOREHEADER)lpbi)->bcHeight; - lpbi->biWidth = ((LPBITMAPCOREHEADER)lpbi)->bcWidth; - bCoreHead = TRUE; + wxLogLastError(wxT("GetObject(hDIB)")); + + return 0; } - else + + // how many colours are we going to have in the palette? + DWORD biClrUsed = ds.dsBmih.biClrUsed; + if ( !biClrUsed ) { - // get to the start of the header and read INFOHEADER - _llseek(fh,sizeof(BITMAPFILEHEADER),SEEK_SET); - if (sizeof(BITMAPINFOHEADER) != _lread (fh, (LPSTR)lpbi, sizeof(BITMAPINFOHEADER))) - goto ErrExit; + // biClrUsed field might not be set + biClrUsed = GetNumberOfColours(ds.dsBmih.biBitCount); } - - nNumColors = (WORD)lpbi->biClrUsed; - if ( nNumColors == 0 ) + + if ( !biClrUsed ) { - /* no color table for 24-bit, default size otherwise */ - if (lpbi->biBitCount != 24) - nNumColors = 1 << lpbi->biBitCount; /* standard size table */ + return ConvertToBitmap((BITMAPINFO *)&ds.dsBmih, hdc, ds.dsBm.bmBits); } - - /* fill in some default values if they are zero */ - if (lpbi->biClrUsed == 0) - lpbi->biClrUsed = nNumColors; - - if (lpbi->biSizeImage == 0) + else { - lpbi->biSizeImage = ((((lpbi->biWidth * (DWORD)lpbi->biBitCount) + 31) & ~31) >> 3) - * lpbi->biHeight; + // fake a BITMAPINFO w/o bits, just the palette info + wxCharBuffer bmi(sizeof(BITMAPINFO) + (biClrUsed - 1)*sizeof(RGBQUAD)); + BITMAPINFO *pBmi = (BITMAPINFO *)bmi.data(); + MemoryHDC hDC; + // get the colour table + SelectInHDC sDC(hDC, m_handle); + ::GetDIBColorTable(hDC, 0, biClrUsed, pBmi->bmiColors); + memcpy(&pBmi->bmiHeader, &ds.dsBmih, ds.dsBmih.biSize); + + return ConvertToBitmap(pBmi, hdc, ds.dsBm.bmBits); } - - /* get a proper-sized buffer for header, color table and bits */ - GlobalUnlock(hDIB); - hDIB = GlobalReAlloc(hDIB, lpbi->biSize + - nNumColors * sizeof(RGBQUAD) + - lpbi->biSizeImage, 0); - if (!hDIB) /* can't resize buffer for loading */ - goto ErrExit2; - - lpbi = (LPBITMAPINFOHEADER)GlobalLock(hDIB); - - /* read the color table */ - if (!bCoreHead) - _lread(fh, (LPSTR)(lpbi) + lpbi->biSize, nNumColors * sizeof(RGBQUAD)); - else +} + +/* static */ +HBITMAP wxDIB::ConvertToBitmap(const BITMAPINFO *pbmi, HDC hdc, void *bits) +{ + wxCHECK_MSG( pbmi, 0, wxT("invalid DIB in ConvertToBitmap") ); + + // here we get BITMAPINFO struct followed by the actual bitmap bits and + // BITMAPINFO starts with BITMAPINFOHEADER followed by colour info + const BITMAPINFOHEADER *pbmih = &pbmi->bmiHeader; + + // get the pointer to the start of the real image data if we have a plain + // DIB and not a DIB section (in the latter case the pointer must be passed + // to us by the caller) + if ( !bits ) { - signed int i; - RGBQUAD FAR *pQuad; - RGBTRIPLE FAR *pTriple; - - _lread(fh, (LPSTR)(lpbi) + lpbi->biSize, nNumColors * sizeof(RGBTRIPLE)); - - pQuad = (RGBQUAD FAR *)((LPSTR)lpbi + lpbi->biSize); - pTriple = (RGBTRIPLE FAR *) pQuad; - for (i = nNumColors - 1; i >= 0; i--) + // we must skip over the colour table to get to the image data + // + // colour table either has the real colour data in which case its + // number of entries is given by biClrUsed or is used for masks to be + // used for extracting colour information from true colour bitmaps in + // which case it always have exactly 3 DWORDs + int numColors; + switch ( pbmih->biCompression ) { - pQuad[i].rgbRed = pTriple[i].rgbtRed; - pQuad[i].rgbBlue = pTriple[i].rgbtBlue; - pQuad[i].rgbGreen = pTriple[i].rgbtGreen; - pQuad[i].rgbReserved = 0; + case BI_BITFIELDS: + numColors = 3; + break; + + case BI_RGB: + // biClrUsed has the number of colors but it may be not initialized at + // all + numColors = pbmih->biClrUsed; + if ( !numColors ) + { + numColors = GetNumberOfColours(pbmih->biBitCount); + } + break; + + default: + // no idea how it should be calculated for the other cases + numColors = 0; } + + bits = (char *)pbmih + sizeof(*pbmih) + numColors*sizeof(RGBQUAD); } - - /* offset to the bits from start of DIB header */ - offBits = (WORD)(lpbi->biSize + nNumColors * sizeof(RGBQUAD)); - - if (bf.bfOffBits != 0L) + + HBITMAP hbmp = ::CreateDIBitmap + ( + hdc ? hdc // create bitmap compatible + : (HDC) ScreenHDC(), // with this DC + pbmih, // used to get size &c + CBM_INIT, // initialize bitmap bits too + bits, // ... using this data + pbmi, // this is used for palette only + DIB_RGB_COLORS // direct or indexed palette? + ); + + if ( !hbmp ) { - _llseek(fh,bf.bfOffBits,SEEK_SET); + wxLogLastError(wxT("CreateDIBitmap")); } - - if (lpbi->biSizeImage == lread(fh, (LPSTR)lpbi + offBits, lpbi->biSizeImage)) + + return hbmp; +} + +/* static */ +size_t wxDIB::ConvertFromBitmap(BITMAPINFO *pbi, HBITMAP hbmp) +{ + wxASSERT_MSG( hbmp, wxT("invalid bmp can't be converted to DIB") ); + + // prepare all the info we need + BITMAP bm; + if ( !::GetObject(hbmp, sizeof(bm), &bm) ) { - GlobalUnlock(hDIB); - - hDC = GetDC(NULL); - if (!wxMakeBitmapAndPalette(hDC, hDIB, palette, - bitmap)) - { - ReleaseDC(NULL,hDC); - goto ErrExit2; - } - else - { - ReleaseDC(NULL,hDC); - GlobalFree(hDIB); - result = TRUE; - } + wxLogLastError(wxT("GetObject(bitmap)")); + + return 0; } - else + + // we need a BITMAPINFO anyhow and if we're not given a pointer to it we + // use this one + BITMAPINFO bi2; + + const bool wantSizeOnly = pbi == NULL; + if ( wantSizeOnly ) + pbi = &bi2; + + // just for convenience + const int h = bm.bmHeight; + + // init the header + BITMAPINFOHEADER& bi = pbi->bmiHeader; + wxZeroMemory(bi); + bi.biSize = sizeof(BITMAPINFOHEADER); + bi.biWidth = bm.bmWidth; + bi.biHeight = h; + bi.biPlanes = 1; + bi.biBitCount = bm.bmBitsPixel; + + // memory we need for BITMAPINFO only + DWORD dwLen = bi.biSize + GetNumberOfColours(bm.bmBitsPixel) * sizeof(RGBQUAD); + + // get either just the image size or the image bits + if ( !::GetDIBits + ( + ScreenHDC(), // the DC to use + hbmp, // the source DDB + 0, // first scan line + h, // number of lines to copy + wantSizeOnly ? NULL // pointer to the buffer or + : (char *)pbi + dwLen, // NULL if we don't have it + pbi, // bitmap header + DIB_RGB_COLORS // or DIB_PAL_COLORS + ) ) { -ErrExit: - GlobalUnlock(hDIB); -ErrExit2: - GlobalFree(hDIB); + wxLogLastError(wxT("GetDIBits()")); + + return 0; } - - _lclose(fh); - return(result); + + // return the total size + return dwLen + bi.biSizeImage; } -/* - * FUNCTION : wxMakeBitmapAndPalette - * PURPOSE : Given a DIB, creates a bitmap and corresponding palette - * to be used for a device-dependent representation of - * of the image. - * RETURNS : TRUE --> success. phPal and phBitmap are filled with - * appropriate handles. Caller is responsible - * for freeing objects. - * FALSE --> unable to create objects. both pointer are - * not valid - */ - -static bool wxMakeBitmapAndPalette(HDC hDC, HANDLE hDIB, - HPALETTE * phPal, HBITMAP * phBitmap) +/* static */ +HGLOBAL wxDIB::ConvertFromBitmap(HBITMAP hbmp) { - LPBITMAPINFOHEADER lpInfo; - bool result = FALSE; - HBITMAP hBitmap; - HPALETTE hPalette, hOldPal; - LPSTR lpBits; - - lpInfo = (LPBITMAPINFOHEADER) GlobalLock(hDIB); - - hPalette = wxMakeDIBPalette(lpInfo); - if ( hPalette ) + // first calculate the size needed + const size_t size = ConvertFromBitmap(NULL, hbmp); + if ( !size ) { - // Need to realize palette for converting DIB to bitmap. - hOldPal = SelectPalette(hDC, hPalette, TRUE); - RealizePalette(hDC); - - lpBits = (LPSTR)lpInfo + (WORD)lpInfo->biSize + - (WORD)lpInfo->biClrUsed * sizeof(RGBQUAD); - hBitmap = CreateDIBitmap(hDC, lpInfo, CBM_INIT, lpBits, - (LPBITMAPINFO)lpInfo, DIB_RGB_COLORS); - - SelectPalette(hDC, hOldPal, TRUE); - RealizePalette(hDC); - - if (!hBitmap) - DeleteObject(hPalette); - else - { - *phBitmap = hBitmap; - *phPal = hPalette; - result = TRUE; - } + // conversion to DDB failed? + return NULL; } - - GlobalUnlock (hDIB); // glt - - return(result); -} -/* - * FUNCTION : wxMakeDIBPalette(lpInfo) - * PURPOSE : Given a BITMAPINFOHEADER, create a palette based on - * the color table. - * RETURNS : non-zero - handle of a corresponding palette - * zero - unable to create palette - */ - -HPALETTE wxMakeDIBPalette(LPBITMAPINFOHEADER lpInfo) -{ - LPLOGPALETTE npPal; - RGBQUAD far *lpRGB; - HPALETTE hLogPal; - WORD i; - - /* since biClrUsed field was filled during the loading of the DIB, - * we know it contains the number of colors in the color table. - */ - if (lpInfo->biClrUsed) + HGLOBAL hDIB = ::GlobalAlloc(GMEM_MOVEABLE, size); + if ( !hDIB ) { - npPal = (LPLOGPALETTE)malloc(sizeof(LOGPALETTE) + - (WORD)lpInfo->biClrUsed * sizeof(PALETTEENTRY)); - if (!npPal) - return NULL; - - npPal->palVersion = 0x300; - npPal->palNumEntries = (WORD)lpInfo->biClrUsed; - - /* get pointer to the color table */ - lpRGB = (RGBQUAD FAR *)((LPSTR)lpInfo + lpInfo->biSize); - - /* copy colors from the color table to the LogPalette structure */ - for (i = 0; (DWORD)i < lpInfo->biClrUsed; i++, lpRGB++) - { - npPal->palPalEntry[i].peRed = lpRGB->rgbRed; - npPal->palPalEntry[i].peGreen = lpRGB->rgbGreen; - npPal->palPalEntry[i].peBlue = lpRGB->rgbBlue; - npPal->palPalEntry[i].peFlags = 0; - } - - hLogPal = CreatePalette((LPLOGPALETTE)npPal); - free(npPal); - - return(hLogPal); + // this is an error which does risk to happen especially under Win9x + // and which the user may understand so let him know about it + wxLogError(_("Failed to allocate %luKb of memory for bitmap data."), + (unsigned long)(size / 1024)); + + return NULL; } - - /* 24-bit DIB with no color table. Return default palette. Another - * option would be to create a 256 color "rainbow" palette to provide - * some good color choices. - */ - else - return((HPALETTE) GetStockObject(DEFAULT_PALETTE)); + + if ( !ConvertFromBitmap((BITMAPINFO *)(void *)GlobalPtrLock(hDIB), hbmp) ) + { + // this really shouldn't happen... it worked the first time, why not + // now? + wxFAIL_MSG( wxT("wxDIB::ConvertFromBitmap() unexpectedly failed") ); + + return NULL; + } + + return hDIB; } -bool wxLoadIntoBitmap(wxChar *filename, wxBitmap *bitmap, wxPalette **pal) +#endif // __WXWINCE__ + +// ---------------------------------------------------------------------------- +// palette support +// ---------------------------------------------------------------------------- + +#if wxUSE_PALETTE + +wxPalette *wxDIB::CreatePalette() const { - HBITMAP hBitmap = NULL; - HPALETTE hPalette = NULL; - - bool success = (wxReadDIB(filename, &hBitmap, &hPalette) != 0); - - if (!success) + // GetDIBColorTable not available in eVC3 +#if defined(_WIN32_WCE) && _WIN32_WCE < 400 + return NULL; +#else + wxCHECK_MSG( m_handle, NULL, wxT("wxDIB::CreatePalette(): invalid object") ); + + DIBSECTION ds; + if ( !GetDIBSection(m_handle, &ds) ) { - if (hPalette) - DeleteObject(hPalette); - return FALSE; + wxLogLastError(wxT("GetObject(hDIB)")); + + return 0; } - - if (hPalette) + + // how many colours are we going to have in the palette? + DWORD biClrUsed = ds.dsBmih.biClrUsed; + if ( !biClrUsed ) { -#if wxUSE_PALETTE - if (pal) - { - *pal = new wxPalette; - (*pal)->SetHPALETTE((WXHPALETTE) hPalette); - } - else -#endif // wxUSE_PALETTE - DeleteObject(hPalette); + // biClrUsed field might not be set + biClrUsed = GetNumberOfColours(ds.dsBmih.biBitCount); } - else if (pal) - *pal = NULL; - - if (hBitmap) + + if ( !biClrUsed ) { - BITMAP bm; - GetObject(hBitmap, sizeof(bm), (LPSTR)&bm); - - bitmap->SetHBITMAP((WXHBITMAP) hBitmap); - bitmap->SetWidth(bm.bmWidth); - bitmap->SetHeight(bm.bmHeight); - bitmap->SetDepth(bm.bmPlanes * bm.bmBitsPixel); -#if WXWIN_COMPATIBILITY_2 - bitmap->SetOk(TRUE); -#endif // WXWIN_COMPATIBILITY_2 - return TRUE; + // bitmaps of this depth don't have palettes at all + // + // NB: another possibility would be to return + // GetStockObject(DEFAULT_PALETTE) or even CreateHalftonePalette()? + return NULL; } - else return FALSE; -} -wxBitmap *wxLoadBitmap(wxChar *filename, wxPalette **pal) -{ - wxBitmap *bitmap = new wxBitmap; - if (wxLoadIntoBitmap(filename, bitmap, pal)) - return bitmap; - else + MemoryHDC hDC; + + // LOGPALETTE struct has only 1 element in palPalEntry array, we're + // going to have biClrUsed of them so add necessary space + LOGPALETTE *pPalette = (LOGPALETTE *) + malloc(sizeof(LOGPALETTE) + (biClrUsed - 1)*sizeof(PALETTEENTRY)); + wxCHECK_MSG( pPalette, NULL, wxT("out of memory") ); + + // initialize the palette header + pPalette->palVersion = 0x300; // magic number, not in docs but works + pPalette->palNumEntries = (WORD)biClrUsed; + + // and the colour table + wxCharBuffer rgb(sizeof(RGBQUAD) * biClrUsed); + RGBQUAD *pRGB = (RGBQUAD*)rgb.data(); + SelectInHDC selectHandle(hDC, m_handle); + ::GetDIBColorTable(hDC, 0, biClrUsed, pRGB); + for ( DWORD i = 0; i < biClrUsed; i++, pRGB++ ) { - delete bitmap; + pPalette->palPalEntry[i].peRed = pRGB->rgbRed; + pPalette->palPalEntry[i].peGreen = pRGB->rgbGreen; + pPalette->palPalEntry[i].peBlue = pRGB->rgbBlue; + pPalette->palPalEntry[i].peFlags = 0; + } + + HPALETTE hPalette = ::CreatePalette(pPalette); + + free(pPalette); + + if ( !hPalette ) + { + wxLogLastError(wxT("CreatePalette")); + return NULL; } -} -/* - * - * Function: InitBitmapInfoHeader - * - * Purpose: Does a "standard" initialization of a BITMAPINFOHEADER, - * given the Width, Height, and Bits per Pixel for the - * DIB. - * - * By standard, I mean that all the relevant fields are set - * to the specified values. biSizeImage is computed, the - * biCompression field is set to "no compression," and all - * other fields are 0. - * - * Note that DIBs only allow BitsPixel values of 1, 4, 8, or - * 24. This routine makes sure that one of these values is - * used (whichever is most appropriate for the specified - * nBPP). - * - * Parms: lpBmInfoHdr == Far pointer to a BITMAPINFOHEADER structure - * to be filled in. - * dwWidth == Width of DIB (not in Win 3.0 & 3.1, high - * word MUST be 0). - * dwHeight == Height of DIB (not in Win 3.0 & 3.1, high - * word MUST be 0). - * nBPP == Bits per Pixel for the DIB. - * - */ + wxPalette *palette = new wxPalette; + palette->SetHPALETTE((WXHPALETTE)hPalette); -static void InitBitmapInfoHeader (LPBITMAPINFOHEADER lpBmInfoHdr, - DWORD dwWidth, - DWORD dwHeight, - int nBPP) -{ - // _fmemset (lpBmInfoHdr, 0, sizeof (BITMAPINFOHEADER)); - memset (lpBmInfoHdr, 0, sizeof (BITMAPINFOHEADER)); - - lpBmInfoHdr->biSize = sizeof (BITMAPINFOHEADER); - lpBmInfoHdr->biWidth = dwWidth; - lpBmInfoHdr->biHeight = dwHeight; - lpBmInfoHdr->biPlanes = 1; - - if (nBPP <= 1) - nBPP = 1; - else if (nBPP <= 4) - nBPP = 4; - else if (nBPP <= 8) - nBPP = 8; - /* Doesn't work - else if (nBPP <= 16) - nBPP = 16; - */ - else - nBPP = 24; - - lpBmInfoHdr->biBitCount = nBPP; - lpBmInfoHdr->biSizeImage = WIDTHBYTES (dwWidth * nBPP) * dwHeight; + return palette; +#endif } -LPSTR wxFindDIBBits (LPSTR lpbi) +#endif // wxUSE_PALETTE + +// ---------------------------------------------------------------------------- +// wxImage support +// ---------------------------------------------------------------------------- + +#if wxUSE_IMAGE + +bool wxDIB::Create(const wxImage& image, PixelFormat pf) { - return (lpbi + *(LPDWORD)lpbi + wxPaletteSize (lpbi)); -} + wxCHECK_MSG( image.IsOk(), false, wxT("invalid wxImage in wxDIB ctor") ); -/* - * Function: BitmapToDIB - * - * Purpose: Given a device dependent bitmap and a palette, returns - * a handle to global memory with a DIB spec in it. The - * DIB is rendered using the colors of the palette passed in. - * - * Parms: hBitmap == Handle to device dependent bitmap compatible - * with default screen display device. - * hPal == Palette to render the DDB with. If it's NULL, - * use the default palette. - */ + const int h = image.GetHeight(); + const int w = image.GetWidth(); + + // if we have alpha channel, we need to create a 32bpp RGBA DIB, otherwise + // a 24bpp RGB is sufficient + const bool hasAlpha = image.HasAlpha(); + const int bpp = hasAlpha ? 32 : 24; -HANDLE wxBitmapToDIB (HBITMAP hBitmap, HPALETTE hPal) + if ( !Create(w, h, bpp) ) + return false; + + // DIBs are stored in bottom to top order (see also the comment above in + // Create()) so we need to copy bits line by line and starting from the end + const int srcBytesPerLine = w * 3; + const int dstBytesPerLine = GetLineSize(w, bpp); + const unsigned char *src = image.GetData() + ((h - 1) * srcBytesPerLine); + const unsigned char *alpha = hasAlpha ? image.GetAlpha() + (h - 1)*w + : NULL; + unsigned char *dstLineStart = (unsigned char *)m_data; + for ( int y = 0; y < h; y++ ) + { + // Copy one DIB line. Note that RGB components order is reversed in + // Windows bitmaps compared to wxImage and is actually BGR. + unsigned char *dst = dstLineStart; + if ( alpha ) + { + int x; + + switch ( pf ) + { + case PixelFormat_PreMultiplied: + // Pre-multiply pixel values so that the DIB could be used + // with ::AlphaBlend(). + for ( x = 0; x < w; x++ ) + { + const unsigned char a = *alpha++; + *dst++ = (unsigned char)((src[2] * a + 127) / 255); + *dst++ = (unsigned char)((src[1] * a + 127) / 255); + *dst++ = (unsigned char)((src[0] * a + 127) / 255); + *dst++ = a; + src += 3; + } + break; + + case PixelFormat_NotPreMultiplied: + // Just copy pixel data without changing it. + for ( x = 0; x < w; x++ ) + { + *dst++ = src[2]; + *dst++ = src[1]; + *dst++ = src[0]; + + *dst++ = *alpha++; + src += 3; + } + break; + } + + } + else // no alpha channel + { + for ( int x = 0; x < w; x++ ) + { + *dst++ = src[2]; + *dst++ = src[1]; + *dst++ = src[0]; + src += 3; + } + } + + // pass to the previous line in the image + src -= 2*srcBytesPerLine; + if ( alpha ) + alpha -= 2*w; + + // and to the next one in the DIB + dstLineStart += dstBytesPerLine; + } + + return true; +} + +wxImage wxDIB::ConvertToImage() const { - BITMAP Bitmap; - BITMAPINFOHEADER bmInfoHdr; - LPBITMAPINFOHEADER lpbmInfoHdr; - LPSTR lpBits; - HDC hMemDC; - HANDLE hDIB; - HPALETTE hOldPal = NULL; - - // Do some setup -- make sure the Bitmap passed in is valid, - // get info on the bitmap (like its height, width, etc.), - // then setup a BITMAPINFOHEADER. - - if (!hBitmap) - return NULL; - - if (!GetObject (hBitmap, sizeof (Bitmap), (LPSTR) &Bitmap)) - return NULL; - - InitBitmapInfoHeader (&bmInfoHdr, - Bitmap.bmWidth, - Bitmap.bmHeight, - Bitmap.bmPlanes * Bitmap.bmBitsPixel); - - // Now allocate memory for the DIB. Then, set the BITMAPINFOHEADER - // into this memory, and find out where the bitmap bits go. - - hDIB = GlobalAlloc (GHND, sizeof (BITMAPINFOHEADER) + - wxPaletteSize ((LPSTR) &bmInfoHdr) + bmInfoHdr.biSizeImage); - - if (!hDIB) - return NULL; - - lpbmInfoHdr = (LPBITMAPINFOHEADER) GlobalLock (hDIB); - - *lpbmInfoHdr = bmInfoHdr; - lpBits = wxFindDIBBits ((LPSTR) lpbmInfoHdr); - - - // Now, we need a DC to hold our bitmap. If the app passed us - // a palette, it should be selected into the DC. - - hMemDC = GetDC (NULL); - - if (hPal) + wxCHECK_MSG( IsOk(), wxNullImage, + wxT("can't convert invalid DIB to wxImage") ); + + // create the wxImage object + const int w = GetWidth(); + const int h = GetHeight(); + wxImage image(w, h, false /* don't bother clearing memory */); + if ( !image.IsOk() ) { - hOldPal = SelectPalette (hMemDC, hPal, FALSE); - RealizePalette (hMemDC); + wxFAIL_MSG( wxT("could not allocate data for image") ); + return wxNullImage; } - - // We're finally ready to get the DIB. Call the driver and let - // it party on our bitmap. It will fill in the color table, - // and bitmap bits of our global memory block. - - if (!GetDIBits (hMemDC, hBitmap, 0, Bitmap.bmHeight, lpBits, - (LPBITMAPINFO) lpbmInfoHdr, DIB_RGB_COLORS)) + + const int bpp = GetDepth(); + + // Remember if we have any "real" transparency, i.e. either any partially + // transparent pixels or not all pixels are fully opaque or fully + // transparent. + bool hasAlpha = false; + bool hasOpaque = false; + bool hasTransparent = false; + + if ( bpp == 32 ) { - GlobalUnlock (hDIB); - GlobalFree (hDIB); - hDIB = NULL; + // 32 bit bitmaps may be either 0RGB or ARGB and we don't know in + // advance which one do we have so suppose we have alpha of them and + // get rid of it later if it turns out we didn't. + image.SetAlpha(); } - else - GlobalUnlock (hDIB); - - // Finally, clean up and return. - - if (hOldPal) - SelectPalette (hMemDC, hOldPal, FALSE); - - ReleaseDC (NULL, hMemDC); - - return hDIB; -} -bool wxSaveBitmap(wxChar *filename, wxBitmap *bitmap, wxPalette *palette) -{ - HPALETTE hPalette = 0; -#if wxUSE_PALETTE - if (palette) - hPalette = (HPALETTE) palette->GetHPALETTE(); -#endif // wxUSE_PALETTE - - HANDLE dibHandle = wxBitmapToDIB((HBITMAP) bitmap->GetHBITMAP(), hPalette); - if (dibHandle) + // this is the same loop as in Create() just above but with copy direction + // reversed + const int dstBytesPerLine = w * 3; + const int srcBytesPerLine = GetLineSize(w, bpp); + unsigned char *dst = image.GetData() + ((h - 1) * dstBytesPerLine); + unsigned char *alpha = image.HasAlpha() ? image.GetAlpha() + (h - 1)*w + : NULL; + const unsigned char *srcLineStart = (unsigned char *)GetData(); + for ( int y = 0; y < h; y++ ) { - bool success = (wxWriteDIB(filename, dibHandle) != 0); - GlobalFree(dibHandle); - return success; + // copy one DIB line + const unsigned char *src = srcLineStart; + for ( int x = 0; x < w; x++ ) + { + dst[2] = *src++; + dst[1] = *src++; + dst[0] = *src++; + + if ( bpp == 32 ) + { + // wxImage uses non premultiplied alpha so undo + // premultiplication done in Create() above + const unsigned char a = *src; + *alpha++ = a; + + // Check what kind of alpha do we have. + switch ( a ) + { + case 0: + hasTransparent = true; + break; + + default: + // Anything in between means we have real transparency + // and must use alpha channel. + hasAlpha = true; + break; + + case 255: + hasOpaque = true; + break; + } + + if ( a > 0 ) + { + dst[0] = (dst[0] * 255) / a; + dst[1] = (dst[1] * 255) / a; + dst[2] = (dst[2] * 255) / a; + } + + src++; + } + + dst += 3; + } + + // pass to the previous line in the image + dst -= 2*dstBytesPerLine; + if ( alpha ) + alpha -= 2*w; + + // and to the next one in the DIB + srcLineStart += srcBytesPerLine; } - else return FALSE; + + if ( hasOpaque && hasTransparent ) + hasAlpha = true; + + if ( !hasAlpha && image.HasAlpha() ) + image.ClearAlpha(); + + return image; } +#endif // wxUSE_IMAGE + +#endif // wxUSE_WXDIB