/*
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 and we shouldn't use
- GetBitmapBits() at all because we can't do it with it)
+ caling GetDIBits() in the DC we use with it.
*/
// ============================================================================
// calculate the number of palette entries needed for the bitmap with this
// number of bits per pixel
-static WORD wxGetNumOfBitmapColors(WORD bitsPerPixel)
+static inline WORD wxGetNumOfBitmapColors(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 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
// ============================================================================
static const int infosize = sizeof(BITMAPINFOHEADER);
BITMAPINFO *info = (BITMAPINFO *)malloc(infosize);
- wxCHECK_MSG( info, NULL, _T("malloc(BITMAPINFO) failed") );
+ wxCHECK_MSG( info, false, _T("malloc(BITMAPINFO) failed") );
memset(info, 0, infosize);
{
wxCHECK_MSG( bmp.Ok(), false, _T("wxDIB::Create(): invalid bitmap") );
- const int w = bmp.GetWidth();
- const int h = bmp.GetHeight();
- int d = bmp.GetDepth();
- if ( d == -1 )
- d = wxDisplayDepth();
+ // this bitmap could already be a DIB section in which case we don't need
+ // to convert it to DIB
+ HBITMAP hbmp = GetHbitmapOf(bmp);
- if ( !Create(w, h, d) )
- return false;
+ DIBSECTION ds;
+ if ( GetDIBSection(hbmp, &ds) )
+ {
+ m_handle = hbmp;
- // we could have used GetDIBits() too but GetBitmapBits() is simpler
- if ( !::GetBitmapBits
- (
- GetHbitmapOf(bmp), // the source DDB
- GetLineSize(w, d)*h, // the number of bytes to copy
- m_data // the pixels will be copied here
- ) )
+ // 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
{
- wxLogLastError(wxT("GetDIBits()"));
+ const int w = bmp.GetWidth();
+ const int h = bmp.GetHeight();
+ int d = bmp.GetDepth();
+ if ( d == -1 )
+ d = wxDisplayDepth();
- return 0;
+ if ( !Create(w, h, d) )
+ return false;
+
+ if ( !GetDIBSection(m_handle, &ds) )
+ {
+ // we've just created a new DIB section, why should this fail?
+ wxFAIL_MSG( _T("GetObject(DIBSECTION) unexpectedly failed") );
+
+ return false;
+ }
+
+ if ( !::GetDIBits
+ (
+ ScreenHDC(), // the DC to use
+ hbmp, // the source DDB
+ 0, // first scan line
+ h, // 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()"));
+
+ return 0;
+ }
}
return true;
if ( ok )
{
DIBSECTION ds;
- if ( !::GetObject(m_handle, sizeof(ds), &ds) )
+ if ( !GetDIBSection(m_handle, &ds) )
{
wxLogLastError(_T("GetObject(hDIB)"));
}
// 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) )
+ if ( !GetDIBSection(m_handle, &ds) )
{
wxLogLastError(_T("GetObject(hDIB)"));
return;
wxCHECK_MSG( m_handle, 0, _T("wxDIB::CreateDDB(): invalid object") );
DIBSECTION ds;
- if ( !::GetObject(m_handle, sizeof(ds), &ds) )
+ if ( !GetDIBSection(m_handle, &ds) )
{
wxLogLastError(_T("GetObject(hDIB)"));
if ( !bits )
{
// we must skip over the colour table to get to the image data
-
- // biClrUsed has the number of colors but it may be not initialized at
- // all
- int numColors = pbmih->biClrUsed;
- if ( !numColors )
+ //
+ // 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 )
{
- numColors = wxGetNumOfBitmapColors(pbmih->biBitCount);
+ 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 = wxGetNumOfBitmapColors(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);
HBITMAP hbmp = ::CreateDIBitmap
(
hdc ? hdc // create bitmap compatible
- : ScreenHDC(), // with this DC
+ : (HDC) ScreenHDC(), // with this DC
pbmih, // used to get size &c
CBM_INIT, // initialize bitmap bits too
bits, // ... using this data
}
/* static */
+#ifdef __DIGITALMARS__
+extern "C"
+#endif
HGLOBAL wxDIB::ConvertFromBitmap(HBITMAP hbmp)
{
// first calculate the size needed
return NULL;
}
- if ( !ConvertFromBitmap((BITMAPINFO *)GlobalHandle(hDIB), hbmp) )
+ if ( !ConvertFromBitmap((BITMAPINFO *)(void *)GlobalPtr(hDIB), hbmp) )
{
// this really shouldn't happen... it worked the first time, why not
// now?
wxCHECK_MSG( m_handle, NULL, _T("wxDIB::CreatePalette(): invalid object") );
DIBSECTION ds;
- if ( !::GetObject(m_handle, sizeof(ds), &ds) )
+ if ( !GetDIBSection(m_handle, &ds) )
{
wxLogLastError(_T("GetObject(hDIB)"));