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DrawDibBegin function (vfw.h)

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The DrawDib function changes parameters of a DrawDib DC or initializes a new DrawDib DC.

Syntax

BOOL VFWAPI DrawDibBegin(
  HDRAWDIB           hdd,
  HDC                hdc,
  int                dxDst,
  int                dyDst,
  LPBITMAPINFOHEADER lpbi,
  int                dxSrc,
  int                dySrc,
  UINT               wFlags
);

Parameters

hdd

Handle to a DrawDib DC.

hdc

Handle to a DC for drawing. This parameter is optional.

dxDst

Width, in MM_TEXT client units, of the destination rectangle.

dyDst

Height, in MM_TEXT client units, of the destination rectangle.

lpbi

Pointer to a BITMAPINFOHEADER structure containing the image format. The color table for the DIB follows the image format and the biHeight member must be a positive value.

dxSrc

Width, in pixels, of the source rectangle.

dySrc

Height, in pixels, of the source rectangle.

wFlags

Applicable flags for the function. The following values are defined.

Value Meaning
DDF_ANIMATE Allows palette animation. If this value is present, DrawDib reserves as many entries as possible by setting PC_RESERVED in the palPalEntry array entries of the LOGPALETTE structure, and the palette can be animated by using the DrawDibChangePalette function. If your application uses the DrawDibBegin function with the DrawDibDraw function, set this value with DrawDibBegin rather than DrawDibDraw.
DDF_BACKGROUNDPAL Realizes the palette used for drawing as a background task, leaving the current palette used for the display unchanged. (This value is mutually exclusive of DDF_SAME_HDC.)
DDF_BUFFER Causes DrawDib to try to use an off-screen buffer so DDF_UPDATE can be used. This disables decompression and drawing directly to the screen. If DrawDib is unable to create an off-screen buffer, it will decompress or draw directly to the screen. For more information, see the DDF_UPDATE and DDF_DONTDRAW values described for DrawDibDraw.
DDF_DONTDRAW Current image is not drawn, but is decompressed. DDF_UPDATE can be used later to draw the image. This flag supersedes the DDF_PREROLL flag.
DDF_FULLSCREEN Not supported.
DDF_HALFTONE Always dithers the DIB to a standard palette regardless of the palette of the DIB. If your application uses DrawDibBegin with DrawDibDraw, set this value with DrawDibBegin rather than DrawDibDraw.
DDF_JUSTDRAWIT Draws the image by using GDI. Prohibits DrawDib functions from decompressing, stretching, or dithering the image. This strips DrawDib of capabilities that differentiate it from the StretchDIBits function.
DDF_SAME_DRAW Use the current drawing parameters for DrawDibDraw. Use this value only if lpbi, dxDest, dyDest, dxSrc, and dySrc have not changed since using DrawDibDraw or DrawDibBegin. This flag supersedes the DDF_SAME_DIB and DDF_SAME_SIZE flags.
DDF_SAME_HDC Use the current DC handle and the palette currently associated with the DC.
DDF_UPDATE Last buffered bitmap needs to be redrawn. If drawing fails with this value, a buffered image is not available and a new image needs to be specified before the display can be updated.

Return value

Returns TRUE if successful or FALSE otherwise.

Remarks

This function prepares to draw a DIB specified by lpbi to the DC. The image is stretched to the size specified by dxDest and dyDest. If dxDest and dyDest are set to −1, the DIB is drawn to a 1:1 scale without stretching.

You can update the flags of a DrawDib DC by reissuing DrawDibBegin, specifying the new flags, and changing at least one of the following settings: dxDest, dyDest, lpbi, dxSrc, or dySrc.

If the parameters of DrawDibBegin have not changed, subsequent calls to the function have no effect.

Requirements

Requirement Value
Minimum supported client Windows 2000 Professional [desktop apps only]
Minimum supported server Windows 2000 Server [desktop apps only]
Target Platform Windows
Header vfw.h
Library Vfw32.lib
DLL Msvfw32.dll

See also

DrawDib Functions