dib.cpp

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//----------------------------------------------------------------------------
// ObjectWindows
// Copyright (c) 1992, 1996 by Borland International, All Rights Reserved
//
/// \file
/// Implementation of TDib class, an encapsulation of Device Independent Bitmaps
/// on disk and in memory.
//----------------------------------------------------------------------------
#include <owl/pch.h>
 
#include <owl/gdiobjec.h>
#include <owl/metafile.h>
#include <owl/clipboar.h>
#include <owl/except.h>
#include <owl/file.h>
#include <owl/wsyscls.h>
 
#if defined(__BORLANDC__)
# pragma option -w-ccc // Disable "Condition is always true/false"
#endif
 
#define BFT_BITMAP 0x4d42   /* 'BM' */
 
using namespace std;
 
namespace owl {
 
OWL_DIAGINFO;
DIAG_DECLARE_GROUP(OwlGDI);        // General GDI diagnostic group
 
//
// Internal DIB file Read/Write functions talk to this IO implementation
//
class TFileIO : public TDib::IFileIn, public TDib::IFileOut {
  public:
    TFileIO(TFile& file) : File(file) {}
 
    virtual long Read(void * buffer, long size)
                 {
                   return File.Read(buffer, size);
                 }
    virtual void Skip(long size)
                 {
                   File.Seek(size, TFile::cur);
                 }
    virtual bool Write(void * buffer, long size)
                 {
                   return File.Write(buffer, size);
                 }
 
  private:
    TFile& File;
};
 
 
//
/// Given a BITMAPINFOHEADER, allocate a global buffer for Handle & init Info
//
void
TDib::InfoFromHeader(const BITMAPINFOHEADER& infoHeader)
{
  // Allocate & lock down the actual single memory block used by this DIB
  //
  int maskAlloc = infoHeader.biCompression==BI_BITFIELDS ? 3*sizeof(uint32) : 0;
  int colorAlloc = int(infoHeader.biClrUsed * sizeof(RGBQUAD));   // Color table size in mem
  IsResHandle = false;
  uint32 size = sizeof(BITMAPINFOHEADER) + maskAlloc + colorAlloc + infoHeader.biSizeImage;
  Handle = ::GlobalAlloc(GMEM_MOVEABLE, size);
  if (!Handle)
    TXOutOfMemory::Raise();
 
  // Setup Info ptr & copy over working infoHeader. Finish by using
  // InfoFromHandle to update all members from Info.
  //
  Info = reinterpret_cast<LPBITMAPINFO>(::GlobalLock(Handle));
  Info->bmiHeader = infoHeader;
 
  InfoFromHandle();
}
TDib::InfoFromHeader(const BITMAPINFOHEADER& infoHeader) {…}
 
//
/// Locks the global/res handle if needed and extracts the pointers and cached info
/// maintained as member variables from Info.
///
/// Needs only Info setup, or if Info is 0 then Handle & IsResHandle setup
//
void
TDib::InfoFromHandle()
{
  // Get the BITMAPINFO Info from the handle if needed
  //
  if (!Info) {
    if (IsResHandle)
      Info = reinterpret_cast<LPBITMAPINFO>(::LockResource(Handle));
    else
      Info = reinterpret_cast<LPBITMAPINFO>(::GlobalLock(Handle));
    if (!Info)
      TXGdi::Raise(IDS_INVALIDDIBHANDLE);
  }
 
  // Fail if the header does not look OK
  //
  if (Info->bmiHeader.biSize != sizeof(BITMAPINFOHEADER)) {
    if (!IsResHandle)
      ::GlobalUnlock(Handle);
    TXGdi::Raise(IDS_INVALIDDIBHANDLE);
  }
 
  // Determine if there is a bit mask (used by 16 & 32 bpp bmps) and where
  // the color table starts
  //
  if (Info->bmiHeader.biCompression == BI_BITFIELDS) {
    Mask = reinterpret_cast<uint32 *>(Info->bmiColors);
    Colors = reinterpret_cast<TRgbQuad *>(reinterpret_cast<char *>(Info->bmiColors) + 3 * sizeof(uint32));
  }
  else {
    Mask = nullptr;
    Colors = static_cast<TRgbQuad *>(Info->bmiColors);
  }
 
  // Figure out the number of colors in the color table using biClrsUsed &
  // biBitCount.
  //
  NumClrs = Info->bmiHeader.biClrUsed
              ? Info->bmiHeader.biClrUsed
              : NColors(Info->bmiHeader.biBitCount);
 
  Bits = reinterpret_cast<char *>(Colors) + static_cast<int>(NumClrs) * sizeof(RGBQUAD);
 
  // Zero out Colors if there is no color table.
  //
  if (!NumClrs)
    Colors = nullptr;
 
  Mode = DIB_RGB_COLORS;
}
TDib::InfoFromHandle() {…}
 
//
/// Under Win32, resources are read-only. So, to allow for modification of the
/// Dib, a copy must be made.
//
void
TDib::ResToMemHandle()
{
  const char* begin = reinterpret_cast<const char*>(Info);
  const char* end = static_cast<const char*>(Bits) + Info->bmiHeader.biSizeImage;
  size_t size = end - begin;
  HANDLE tempHandle = ::GlobalAlloc(GMEM_MOVEABLE, size);
  if (!tempHandle)
    TXOutOfMemory::Raise();
 
  void* tempInfo = ::GlobalLock(tempHandle);
  memcpy(tempInfo, Info, size);
 
  // Handle will now be a memory handle, & no longer a res handle
  // Update Bits pointer & other members that may have moved.
  //
  Handle = tempHandle;
  Info = reinterpret_cast<LPBITMAPINFO>(tempInfo);
  IsResHandle = false;
  InfoFromHandle();
}
TDib::ResToMemHandle() {…}
 
 
//
/// Creates a TDib object and sets the Handle data member to the given borrowed
/// handle. The ShouldDelete data member defaults to false, ensuring that the
/// borrowed handle will not be deleted when the C++ object is destroyed.
//
TDib::TDib(HGLOBAL handle, TAutoDelete autoDelete)
:
  TGdiBase(handle, autoDelete),
  Info(nullptr), IsResHandle(false)
{
  InfoFromHandle();
}
TDib::TDib(HGLOBAL handle, TAutoDelete autoDelete) {…}
 
 
//
/// Constructs a TDib object with a handle borrowed from the given Clipboard.
//
TDib::TDib(const TClipboard& clipboard)
:
  TGdiBase(clipboard.GetClipboardData(CF_DIB)),
  Info(nullptr), IsResHandle(false)
{
  InfoFromHandle();
}
TDib::TDib(const TClipboard& clipboard) {…}
 
 
//
/// This public copy constructor creates a complete copy of the given src object as
/// in:
/// \code
/// TDib mySrc = yourSrc;
/// \endcode
//
TDib::TDib(const TDib& src)
:
  IsResHandle(false)
{
  PRECONDITION(src.Info != 0);
 
//  long size = ::GlobalSize(src.Handle); // !CQ assumes src has a mem handle
  uint32 size = src.SizeDib();
  Handle = ::GlobalAlloc(GMEM_MOVEABLE, size);
  if (!Handle)
    TXOutOfMemory::Raise();
 
  Info = reinterpret_cast<LPBITMAPINFO>(::GlobalLock(Handle));
  memcpy(Info, src.Info, size);
 
  Mask = reinterpret_cast<uint32 *>(src.Mask ?
           reinterpret_cast<char *>(Info) + (reinterpret_cast<char *>(src.Mask) - reinterpret_cast<char *>(src.Info)) : nullptr);
  Bits = reinterpret_cast<char *>(Info) + (reinterpret_cast<char *>(src.Bits) - reinterpret_cast<char *>(src.Info));
 
  NumClrs = src.NumClrs;
 
  // Zero out Colors if there is no color table.
  //
  if (!NumClrs)
    Colors = nullptr;
  else
    Colors = reinterpret_cast<TRgbQuad *>(reinterpret_cast<char *>(Info) + (reinterpret_cast<char *>(src.Colors) - reinterpret_cast<char *>(src.Info)));
 
  Mode = src.Mode;
}
TDib::TDib(const TDib& src) {…}
 
 
//
/// Destruct a TDib by unlocking & freeing its global memory handle as required
//
TDib::~TDib()
{
  if (!Handle || IsResHandle) return;
  ::GlobalUnlock(Handle);
  if (ShouldDelete)
    ::GlobalFree(Handle);
}
TDib::~TDib() {…}
 
 
//
/// Converts the existing color table in place to use palette relative values. The
/// palette that is passed is used as a reference. Returns true if the call is
/// successful; otherwise returns false.
///
/// Makes sure that color table is RGB
//
bool
TDib::ChangeModeToPal(const TPalette& pal)
{
  if (Mode != DIB_RGB_COLORS)
    return false;
 
  uint16 nEntries = pal.GetNumEntries();
 
  for (int c = 0; c < NumClrs; c++) {
    uint16 index = uint16(c);
    for (uint16 i = 0; i < nEntries; i++) {
      PALETTEENTRY pe; //getting all entries one time up front would be faster
      pal.GetPaletteEntry(i, pe);
      if (pe.peRed == Colors[c].rgbRed &&
          pe.peGreen == Colors[c].rgbGreen &&
          pe.peBlue == Colors[c].rgbBlue) {
        index = i;
        break;
      }
    }
    (reinterpret_cast<uint16*>(Colors))[c] = index;
  }
  Mode = DIB_PAL_COLORS;
  return true;
}
TDib::ChangeModeToPal(const TPalette& pal) {…}
 
 
//
/// Converts the existing color table in place to use absolute RGB values. The
/// palette that is passed is used as a reference. Returns true if the call is
/// successful; otherwise returns false.
///
/// Makes sure that color table is pal relative & that there is enough space
//
bool
TDib::ChangeModeToRGB(const TPalette& pal)
{
  if (Mode != DIB_PAL_COLORS ||
      static_cast<uint>(reinterpret_cast<char*>(Bits) - reinterpret_cast<char*>(Info)) < NumClrs*sizeof(RGBQUAD))
    return false;
 
  uint16 nEntries = pal.GetNumEntries();
 
  for (int c = static_cast<int>(NumClrs)-1; c >= 0; c--) {
    uint16 i = (reinterpret_cast<uint16*>(Colors))[c];
    if (i >= nEntries)
      i = 0;
    PALETTEENTRY pe;
    pal.GetPaletteEntry(i, pe);
    Colors[c].rgbRed = pe.peRed;
    Colors[c].rgbGreen = pe.peGreen;
    Colors[c].rgbBlue = pe.peBlue;
  }
  Mode = DIB_RGB_COLORS;
  return true;
}
TDib::ChangeModeToRGB(const TPalette& pal) {…}
 
 
//
// Get, set, find and map the color table entries as colors (RGBQUADs)
 
//
/// Returns the color for the given palette entry.
//
TColor
TDib::GetColor(int entry) const
{
  if (entry >= 0 && entry < NumClrs)
    if (Mode == DIB_RGB_COLORS)
      return GetColors()[entry];
 
  return TColor();
}
TDib::GetColor(int entry) const {…}
 
 
//
/// Sets the given color for the given palette entry.
//
void
TDib::SetColor(int entry, const TColor& color)
{
  if (entry >= 0 && entry < NumClrs)
    if (Mode == DIB_RGB_COLORS)
      GetColors()[entry] = color;
}
TDib::SetColor(int entry, const TColor& color) {…}
 
 
//
/// Returns the palette entry for the given color.
//
int
TDib::FindColor(const TColor& color)
{
  for (int entry = 0; entry < NumClrs; entry++)
    if (color == GetColors()[entry])  // Small data model requires this order
      return entry;
  return -1;
}
TDib::FindColor(const TColor& color) {…}
 
 
//
/// Maps the first or all occurances of fromColor to the toColor in the current palette of this DIB.
/// Returns the palette entry for the given color. Returns the palette entry for the
/// toColor argument.
//
int
TDib::MapColor(const TColor& fromColor, const TColor& toColor, bool mapAll)
{
  int count = 0;
  for (int entry = 0; entry < NumClrs; entry++)
    if (fromColor == GetColors()[entry]) {  // Small data model requires this order
      GetColors()[entry] = toColor;
      count++;
      if (!mapAll)
        break;
    }
  return count;
}
TDib::MapColor(const TColor& fromColor, const TColor& toColor, bool mapAll) {…}
 
 
//
// Get, set, find and map the color table entries as palette indices
//
uint16
TDib::GetIndex(int entry) const
{
  if (entry >= 0 && entry < NumClrs)
    if (Mode == DIB_PAL_COLORS)
      return (reinterpret_cast<const uint16*>(GetColors()))[entry];
 
  return 0;
}
TDib::GetIndex(int entry) const {…}
 
 
//
/// Sets the given index for the given entry.
//
void
TDib::SetIndex(int entry, uint16 index)
{
  if (entry >= 0 && entry < NumClrs)
    if (Mode == DIB_PAL_COLORS)
      (reinterpret_cast<uint16*>(GetColors()))[entry] = index;
}
TDib::SetIndex(int entry, uint16 index) {…}
 
 
//
/// Returns the palette entry corresponding to the given index.
//
int
TDib::FindIndex(uint16 index)
{
  for (int entry = 0; entry < NumClrs; entry++)
    if (GetIndices()[entry] == index)
      return entry;
  return -1;
}
TDib::FindIndex(uint16 index) {…}
 
 
//
/// Maps the fromIndex to the toIndex in the current palette of this DIB.
/// Returns the palette entry for the toIndex argument.
//
int
TDib::MapIndex(uint16 fromIndex, uint16 toIndex, bool doAll)
{
  int count = 0;
  for (int entry = 0; entry < NumClrs; entry++)
    if (GetIndices()[entry] == fromIndex) {
      GetIndices()[entry] = toIndex;
      count++;
      if (!doAll)
        break;
    }
  return count;
}
TDib::MapIndex(uint16 fromIndex, uint16 toIndex, bool doAll) {…}
 
 
//
/// Maps the UI colors to the value specified in the parameter, mapColors, which is
/// one of the values of the Map enum. Use this function to get the colors for the
/// face shading on push buttons, the highlighting for a selected control button,
/// the text on push buttons, the shade of the window frame and the background
/// color.
//
/// Use MapColor to map selected standard UI colors in this DIB to their
/// current system values. Also can map a background color. Used to update a
/// UI DIB to current colors before rendering.
///
/// - \c \b   LtGray   -> 3d Face
/// - \c \b   Black    -> Button Text
/// - \c \b   Gray     -> 3d Shadow
/// - \c \b   White    -> 3d Hilight
/// - \c \b   Magenta  -> Window Frame
/// - \c \b   LtYellow -> bkColor
//
void
TDib::MapUIColors(uint mapColors, const TColor* bkColor)
{
  if (mapColors & TDib::MapFace)
#ifdef UNIX
    MapColor(TColor::LtGray, TColor::SysWindow);  //copied from old owl (DLN UNIX color
                                                  //problem TColor::Sys3dFace);) (04-16-01 JAM)
#else
    MapColor(TColor::LtGray, TColor::Sys3dFace);
#endif
 
  if (mapColors & TDib::MapText)
    MapColor(TColor::Black, TColor::SysBtnText);
  if (mapColors & TDib::MapShadow)
    MapColor(TColor::Gray, TColor::Sys3dShadow);
  if (mapColors & TDib::MapHighlight)
    MapColor(TColor::White, TColor::Sys3dHilight);
  if (mapColors & TDib::MapFrame)
    MapColor(TColor::LtMagenta, TColor::SysWindowFrame);
  if (bkColor)
    MapColor(TColor::LtYellow, *bkColor);
}
TDib::MapUIColors(uint mapColors, const TColor* bkColor) {…}
 
 
//
/// Moves this dib to the clipboard. Ownership of the DIB handle is passed to the
/// clipboard.
//
void
TDib::ToClipboard(TClipboard& clipboard)
{
  if (Handle) {
    if (IsResHandle) {
    }
    else {
      ::GlobalUnlock(Handle);
    }
    clipboard.SetClipboardData(CF_DIB, Handle);
    ShouldDelete = false;
    Info = nullptr;
    Bits = nullptr;
    Handle = nullptr;
  }
}
TDib::ToClipboard(TClipboard& clipboard) {…}
 
 
//
/// Creates a DIB object from the given resource file (.bmp).
//
TDib::TDib(LPCTSTR filename)
{
  if (!ReadFile(filename))
    TXGdi::Raise(IDS_GDIFILEREADFAIL);
}
TDib::TDib(LPCTSTR filename) {…}
 
//
/// String-aware overload
//
TDib::TDib(const tstring& filename)
{
  if (!ReadFile(filename))
    TXGdi::Raise(IDS_GDIFILEREADFAIL);
}
TDib::TDib(const tstring& filename) {…}
 
 
//
/// Creates a DIB from the file.
//
TDib::TDib(TFile& file, bool readFileHeader)
{
  if (!Read(file, readFileHeader))
    TXGdi::Raise(IDS_GDIFILEREADFAIL);
}
TDib::TDib(TFile& file, bool readFileHeader) {…}
 
//
/// Creates a DIB from the file stream.
//
TDib::TDib( istream& is, bool readFileHeader)
{
  if (!Read(is, readFileHeader))
    TXGdi::Raise(IDS_GDIFILEREADFAIL);
}
TDib::TDib( istream& is, bool readFileHeader) {…}
 
 
//
/// Constructs an empty DIB for use by derived classes.
//
TDib::TDib()
:
  Info(nullptr), Mask(nullptr), Colors(nullptr), Bits(nullptr),
  NumClrs(0),
  IsResHandle(false)
{
  // Handle must be set by derived class
  // InfoFromHandle() or equivalent must then be called
}
TDib::TDib() {…}
 
 
//
/// Tests if the passed file is a Windows 3.x (or PM 1.x) DIB and if so read it.
///
/// Returns true if Dib was read OK.
//
bool
TDib::ReadFile(const tstring& name)
{
  TFile file(name, TFile::ReadOnly|TFile::OpenExisting);
  if (!file.IsOpen()) {
    TRACEX(OwlGDI, 0, "Cannot open bitmap file '" << name << "' to read");
    return false;
  }
 
  // Read the bitmap in, file header & all
  //
  bool ok = Read(file, true);
 
  file.Close();
  return ok;
}
TDib::ReadFile(const tstring& name) {…}
 
 
//
/// Read a Windows 3.x or PM 1.x device independent bitmap from a TFile
/// Return true iff Dib was read OK
//
bool
TDib::Read(TFile& file, bool readFileHeader)
{
  TFileIO in(file);
  return Read(in, readFileHeader);
}
TDib::Read(TFile& file, bool readFileHeader) {…}
 
//
// The ios version of the DIB read requires large data model since the buffers
// are quite large.
//
 
//
//
//
class TStreamIn : public TDib::IFileIn {
  public:
    TStreamIn(istream& is) : Is(is) {}
 
    virtual long Read(void* buffer, long size)
    {
      PRECONDITION(size >= 0);
      streamsize n = Is.read(static_cast<char*>(buffer), size).gcount();
 
      // Note: 'n' cannot be larger than 'size'; hence we can cast unchecked.
      // TODO: Widen the return type to avoid the narrowing cast.
 
      return static_cast<long>(n);
    }
 
    virtual void Skip(long size)
    {
      Is.seekg(size, ios::cur);
    }
 
  private:
    istream& Is;
};
 
//
//
/// Read a Windows 3.0 or PM 1.X device independent bitmap from an istream
///
/// Checks header, read Info, palette and bitmap.  PM DIBs can be converted to
/// Win 3.x DIBs on the fly.
///
/// Returns true iff DIB was read OK
//
bool
TDib::Read( istream& is, bool readFileHeader)
{
  TStreamIn in(is);
  return Read(in, readFileHeader);
}
TDib::Read( istream& is, bool readFileHeader) {…}
 
 
//
/// Reads a Windows 3.0 or PM 1.X device independent bitmap. (.BMP) from an
/// implementor of TDib's IFileIn interface
///
/// Checks header, read Info, palette and bitmap.  PM Dibs are converted to
/// Windows 3.x Dibs on the fly.
///
/// Returns true iff Dib was read OK
//
bool
TDib::Read(IFileIn& in, bool readFileHeader)
{
  long offBits = 0;
 
  // Read file header and verify the signature. Grab bfOffBits if it is != 0
  // We ignore all other information in the file header since some applications
  // do not put correct information in the fields...
  //
  if (readFileHeader) {
    BITMAPFILEHEADER bmf;
    if (static_cast<size_t>(in.Read(&bmf, sizeof(bmf))) != sizeof(bmf) || bmf.bfType != BFT_BITMAP) {
      TRACEX(OwlGDI, 0, "Not a Windows 3.x or PM 1.x bitmap file");
      TXBadFormat::Raise();
      return false;
    }
    if (bmf.bfOffBits)
      offBits = bmf.bfOffBits - sizeof(BITMAPFILEHEADER);
  }
 
  // Read bitmap header size & check it. It must be one of the two known header
  // sizes.
  // Will add BITMAPV4HEADER support when available
  //
  uint32 headerSize;
  size_t n = static_cast<size_t>(in.Read(&headerSize, sizeof(headerSize)));
  if (n != sizeof(headerSize) ||
    (headerSize != sizeof(BITMAPCOREHEADER) && headerSize != sizeof(BITMAPINFOHEADER)))
  {
    TRACEX(OwlGDI, 0, "Not a Windows 3.x or PM 1.x bitmap file");
    TXBadFormat::Raise();
    return false;
  }
 
  // Prepare to build or read a header that is an Info (Windows) type
  //
  BITMAPINFOHEADER infoHeader;
  infoHeader.biSize = sizeof(BITMAPINFOHEADER);
 
  // If this is a PM 1.x DIB, read the core header & copy over to the Info header
  //
  bool   isCore = headerSize == sizeof(BITMAPCOREHEADER);
  if (isCore) {
    // Read in the rest of the core header, aborting if it is truncated
    //
    BITMAPCOREHEADER coreHeader;
    int size = static_cast<int>(headerSize)-sizeof(uint32);
    if (in.Read(&coreHeader.bcWidth, size) != size) {
      TRACEX(OwlGDI, 0, "Invalid PM 1.x DIB Header");
      TXBadFormat::Raise();
      return false;
    }
 
    // Copy core fields over to info fields, filling in the missing pieces
    //
    infoHeader.biWidth = coreHeader.bcWidth;
    infoHeader.biHeight = coreHeader.bcHeight;
    infoHeader.biPlanes = coreHeader.bcPlanes;
    infoHeader.biBitCount = coreHeader.bcBitCount;
    infoHeader.biCompression = BI_RGB;  // No compression
    infoHeader.biSizeImage = 0;         // Calculate this below
    infoHeader.biXPelsPerMeter = 0;     // Zero is OK
    infoHeader.biYPelsPerMeter = 0;     // Zero is OK
    infoHeader.biClrUsed = 0;           // Calculate this below
    infoHeader.biClrImportant = 0;      // Zero is OK
  }
  // This is a Win 3.x DIB, read the info header
  //
  else {
    // Read in the rest of the info header, aborting if it is truncated
    //
    int size = static_cast<int>(headerSize)-sizeof(uint32);
    if (in.Read(&infoHeader.biWidth, size) != size) {
      TRACEX(OwlGDI, 0, "Invalid Win 3.x DIB Header");
      TXBadFormat::Raise();
      return false;
    }
  }
 
  // Check number of planes. Windows supports only 1 plane DIBs
  //
  if (infoHeader.biPlanes != 1) {
    TRACEX(OwlGDI, 0, "Invalid number of planes in DIB");
    TXBadFormat::Raise();
    return false;
  }
 
  // Fill in the default value for biClrsUsed, if not supplied, using the
  // bit count. Will remain 0 for 16bpp or greater.
  //
  if (!infoHeader.biClrUsed)
    infoHeader.biClrUsed = NColors(infoHeader.biBitCount);
 
  // Some applications do not fill in the biSizeImage field in the header.
  // (Actually the truth is more likely that some drivers do not fill the
  // field in and the apps do not compensate for these buggy drivers.)
  //
  // Therefore, if compression was not used, we (re)compute the size,
  // but if compression is used, we have no choice but to trust the size.
  //
  if (infoHeader.biCompression == BI_RGB ||
      infoHeader.biCompression == BI_BITFIELDS)
    infoHeader.biSizeImage =
        ScanBytes(infoHeader.biWidth,
                  infoHeader.biBitCount) * infoHeader.biHeight;
 
  // Setup all members based on InfoHeader
  //
  InfoFromHeader(infoHeader);
 
  // Read color mask directly into allocated memory
  //
  if (Mask) {
    int size = 3*sizeof(uint32);
    if (in.Read(reinterpret_cast<char *>(Mask), size) != size) {
      TRACEX(OwlGDI, 0, "Could not read DIB color mask");
      ::GlobalUnlock(Handle);
      return false;
    }
  }
 
  // Read color table directly into allocated memory
  // Walk backwards & expand to RGBQUADs if it is a PM Core DIB
  //
  int colorRead = isCore ?          // Color table size on disk
        static_cast<int>(NumClrs) * sizeof(RGBTRIPLE) :
        static_cast<int>(NumClrs) * sizeof(RGBQUAD);
  if (Colors) {
    if (in.Read(reinterpret_cast<char *>(Colors), colorRead) != colorRead) {
      TRACEX(OwlGDI, 0, "Could not read DIB color table");
      ::GlobalUnlock(Handle);
      return false;
    }
    if (isCore) {
      for (int i = int(NumClrs-1); i >= 0; i--) {
        Colors[i].rgbRed = (reinterpret_cast<RGBTRIPLE*>(Colors))[i].rgbtRed;
        Colors[i].rgbGreen = (reinterpret_cast<RGBTRIPLE*>(Colors))[i].rgbtGreen;
        Colors[i].rgbBlue = (reinterpret_cast<RGBTRIPLE*>(Colors))[i].rgbtBlue;
        Colors[i].rgbReserved = 0;
      }
    }
  }
 
  // Locate & Read Bits, skipping Pad if any.
  // Ignore offBits if it is zero, or if less than the current position--it's
  // probably bad
  //
  if (offBits && offBits - static_cast<long>(headerSize+colorRead) > 0)
    in.Skip(offBits - (headerSize+colorRead));
  if (!in.Read(Bits, infoHeader.biSizeImage)) {
    TRACEX(OwlGDI, 0, "Could not read DIB bits");
    return false;
  }
 
  return true;
}
TDib::Read(IFileIn& in, bool readFileHeader) {…}
 
 
//
/// Creates a TDib given a module instance and a resource name or int Id
//
TDib::TDib(HINSTANCE instance, TResId resId)
:
  Info(nullptr), Mask(nullptr), Colors(nullptr), Bits(nullptr),
  NumClrs(0),
  IsResHandle(false)
{
  if (!LoadResource(instance, resId))
    TXGdi::Raise(IDS_GDIRESLOADFAIL);
}
TDib::TDib(HINSTANCE instance, TResId resId) {…}
 
 
//
/// Loads this DIB from the given resource and returns true if successful.
//
bool
TDib::LoadResource(HINSTANCE instance, TResId resId)
{
  PRECONDITION(!Handle);
 
  // First, load the resource into a global memory block.
  //
  HRSRC  resHandle = ::FindResource(instance, resId, RT_BITMAP);
  Handle = resHandle ? ::LoadResource(instance, resHandle) : nullptr;
  if (!Handle) {
    TRACEX(OwlGDI, 0, "Cannot access bitmap resource");
    return false;
  }
  IsResHandle = true;
 
  // Then update our pointers & other info.
  //
  InfoFromHandle();
 
  // Under Win32, resources are read-only. So, to allow for later modification
  // of the Dib, a copy must be made.
  //
  // Could postpone this until dib needed to be written on...
  //
  ResToMemHandle();
 
  return true;
}
TDib::LoadResource(HINSTANCE instance, TResId resId) {…}
 
 
//
/// Writes the DIB into an external file.
///
/// Returns true if the call is successful; otherwise returns false.
//
bool
TDib::WriteFile(const tstring& name)
{
  TFile file(name, TFile::WriteOnly|TFile::PermExclusive|TFile::CreateAlways);
 
  if (!file.IsOpen()) {
    TRACEX(OwlGDI, 0, "Cannot open bitmap file '" << name << "' to write");
    return false;
  }
 
  bool ok = Write(file, true);
 
  file.Close();
  if (!ok) {
    TRACEX(OwlGDI, 0, "Disk error writing file '" << name << "'");
    return false;
  }
  return true;
}
TDib::WriteFile(const tstring& name) {…}
 
 
//
/// Write this DIB to a file object.
//
bool
TDib::Write(TFile& file, bool writeFileHeader)
{
  TFileIO out(file);
  return Write(out, writeFileHeader);
}
TDib::Write(TFile& file, bool writeFileHeader) {…}
 
//
// The ios version of the DIB read requires large data model since the buffers
// are quite large.
//
 
 
//
//
//
class TStreamOut : public TDib::IFileOut {
  public:
    TStreamOut( ostream& os) : Os(os) {}
 
    virtual bool Write(void * buffer, long size)
                 {
                   return Os.write(reinterpret_cast<char*>(buffer), size).good();
                 }
  private:
    ostream& Os;
};
 
//
/// Writes this DIB to an ostream.
//
bool
TDib::Write( ostream& os, bool writeFileHeader)
{
  TStreamOut out(os);
  return Write(out, writeFileHeader);
}
TDib::Write( ostream& os, bool writeFileHeader) {…}
 
 
//
/// Writes the DIB into a file stream.
//
bool
TDib::Write(IFileOut& out, bool writeFileHeader)
{
  size_t size = ::GlobalSize(Handle);
 
  // Write file header.
  //
  if (writeFileHeader)
  {
    size_t bfSize = size + sizeof(BITMAPFILEHEADER);
    if (!IsRepresentable<DWORD>(bfSize))
      return false;
 
    const char* begin = reinterpret_cast<const char*>(Info);
    const char* end = static_cast<const char*>(Bits) + sizeof(BITMAPFILEHEADER);
    size_t bfOffBits = end - begin;
    if (!IsRepresentable<DWORD>(bfOffBits))
      return false;
 
    BITMAPFILEHEADER bmf;
    bmf.bfType = BFT_BITMAP;//'BM';
    bmf.bfSize = static_cast<DWORD>(bfSize);
    bmf.bfReserved1 = 0;
    bmf.bfReserved2 = 0;
    bmf.bfOffBits = static_cast<DWORD>(bfOffBits);
    if (!out.Write(&bmf, sizeof(bmf)))
      return false;
  }
 
  // Write rest of dib, including dib header, color table & bits.
  //
  if (!IsRepresentable<long>(size))
    return false;
  if (!out.Write(Info, static_cast<long>(size))) // TODO: Widen parameter type to avoid this narrowing cast.
    return false;
 
  return true;
}
TDib::Write(IFileOut& out, bool writeFileHeader) {…}
 
 
//
/// Creates a DIB object with the given width, height, number of colors, mode
/// values.
//
TDib::TDib(int width, int height, uint32 nColors, uint16 mode)
{
  PRECONDITION(width && height && nColors);
 
  BITMAPINFOHEADER      infoHeader;
  infoHeader.biSize       = sizeof(BITMAPINFOHEADER);
  infoHeader.biWidth      = width;
  infoHeader.biHeight     = height;
  infoHeader.biPlanes     = 1;
  infoHeader.biBitCount   = NBits(nColors);
  infoHeader.biCompression   = BI_RGB;
  uint32 bytes = ScanBytes(width, infoHeader.biBitCount);
  infoHeader.biSizeImage = bytes * height;
  infoHeader.biXPelsPerMeter = 0;
  infoHeader.biYPelsPerMeter = 0;
  infoHeader.biClrUsed       = infoHeader.biBitCount > 8 ? 0 : nColors;
  infoHeader.biClrImportant  = 0;
 
  // Setup all members based on infoHeader
  //
  InfoFromHeader(infoHeader);
 
  // Initialize the color table--either Palette or RGB
  //
  Mode = mode;
  if (Mode == DIB_PAL_COLORS) {
    // Generate a 1:1 palette relative color table- it can later be translated
    // to RGB given a palette.
    //
    for (uint i = 0; i < nColors; i++)
      (reinterpret_cast<uint16*>(Colors))[i] = static_cast<uint16>(i);
  }
  else if(nColors){
    // Get the system palette and convert to RGB quad format if exist support.
    //
    TScreenDC dc;
    if(dc.GetDeviceCaps(RASTERCAPS) & RC_PALETTE){
      uint clrCnt = ::GetSystemPaletteEntries(dc, 0, nColors, reinterpret_cast<LPPALETTEENTRY>(Colors));
      for (uint32 i = 0; i < clrCnt; i++) {
        Swap(Colors[i].rgbRed, Colors[i].rgbBlue);
        Colors[i].rgbReserved = 0;
      }
    }
  }
}
TDib::TDib(int width, int height, uint32 nColors, uint16 mode) {…}
 
 
//
/// Creates a DIB object from the given resource bitmap and palette. If pal is 0
/// (the default), the default palette is used.
//
TDib::TDib(const TBitmap& bitmap, const TPalette* palette)
{
  BITMAP  bm;
  bitmap.GetObject(bm);
 
  BITMAPINFOHEADER  infoHeader;
  infoHeader.biSize       = sizeof(BITMAPINFOHEADER);
  infoHeader.biWidth      = bm.bmWidth;
  infoHeader.biHeight     = bm.bmHeight;
  infoHeader.biPlanes     = 1;
  uint16 nColors;
  if (palette) {
    palette->GetObject(nColors);
    infoHeader.biBitCount = NBits(nColors);
  }
  else {
    infoHeader.biBitCount = uint16(bm.bmBitsPixel*bm.bmPlanes);
    nColors = static_cast<uint16>(NColors(infoHeader.biBitCount));
  }
  infoHeader.biCompression   = BI_RGB;
  infoHeader.biSizeImage     = ScanBytes(infoHeader.biWidth,
                                         infoHeader.biBitCount) * infoHeader.biHeight;
  infoHeader.biXPelsPerMeter = 0;
  infoHeader.biYPelsPerMeter = 0;
  infoHeader.biClrUsed       = nColors;
  infoHeader.biClrImportant  = 0;
 
  // Setup all members based on infoHeader
  //
  InfoFromHeader(infoHeader);
 
  // Copy pixels from given bitmap into our new empty DIB, selecting palette
  // if provided
  //
  TScreenDC dc;
  if (palette)
    dc.SelectObject(*palette, false);
  dc.GetDIBits(bitmap, StartScan(), NumScans(), Bits, *Info, Usage());
}
TDib::TDib(const TBitmap& bitmap, const TPalette* palette) {…}
 
 
//
/// Modifies this DIB so that the pixels and color table coincide with a given
/// palette.
/// !CQ 8bpp only!
//
void
TDib::MapToPalette(const TPalette& pal)
{
  // Create a mapping from our current color table to the target palette
  //
  uint8 map[256];
  for (int i = 0; i < 256; i++)
    map[i] = static_cast<uint8>(pal.GetNearestPaletteIndex(GetColor(i)));
 
  // Use the map to translate all of the pixels into indexes in the target
  // palette
  //
  uint8 * bits = reinterpret_cast<uint8 *>(GetBits());
  long size = Pitch() * Height();
  while (size--) {
    *bits = map[*bits];
    bits++;
  }
 
  // Now copy the target palette into our color table
  //
  PALETTEENTRY pe[256];
  pal.GetPaletteEntries(0, 256, pe);
  TRgbQuad * colorTab = GetColors();
  for (int j = 0; j < 256; j++) {
    colorTab->rgbRed = pe[j].peRed;
    colorTab->rgbGreen = pe[j].peGreen;
    colorTab->rgbBlue = pe[j].peBlue;
    colorTab++;
  }
}
TDib::MapToPalette(const TPalette& pal) {…}
 
 
} // OWL namespace