DrawDibBegin

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

BOOL DrawDibBegin(

HDRAWDIB hdd,
HDC hdc,
int dxDest,
int dyDest,
LPBITMAPINFOHEADER lpbi,
int dxSrc,
int dySrc,
UINT wFlags
);

Parameters

hdd

Handle of a DrawDib DC.

hdc

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

dxDest and dyDest

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

lpbi

Address of 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 and dySrc

Width and height, in pixels, of the source rectangle.

wFlags

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

DDF_ANIMATE

Allows palette animation. If this value is present, DrawDib reserves as many entries as possible by setting PC_RESERVED in the palPalEntry members 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 supercedes 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 supercedes 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 Values

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.

See Also

BITMAPINFOHEADER, LOGPALETTE, DrawDibChangePalette, DrawDibDraw, StretchDIBits

Software for developers

Delphi Components
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Software for Android Developers

More information resources

MegaDetailed.Net
Unix Manual Pages
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