DrawDibDraw function (vfw.h)
The DrawDibDraw function draws a DIB to the screen.
Syntax
BOOL VFWAPI DrawDibDraw(
HDRAWDIB hdd,
HDC hdc,
int xDst,
int yDst,
int dxDst,
int dyDst,
LPBITMAPINFOHEADER lpbi,
LPVOID lpBits,
int xSrc,
int ySrc,
int dxSrc,
int dySrc,
UINT wFlags
);
Parameters
hdd
Handle to a DrawDib DC.
hdc
Handle to the DC.
xDst
The x-coordinate, in MM_TEXT client coordinates, of the upper left corner of the destination rectangle.
yDst
The y-coordinate, in MM_TEXT client coordinates, of the upper left corner of the destination rectangle.
dxDst
Width, in MM_TEXT client coordinates, of the destination rectangle. If dxDst is −1, the width of the bitmap is used.
dyDst
Height, in MM_TEXT client coordinates, of the destination rectangle. If dyDst is −1, the height of the bitmap is used.
lpbi
Pointer to the BITMAPINFOHEADER structure containing the image format. The color table for the DIB within BITMAPINFOHEADER follows the format and the biHeight member must be a positive value; DrawDibDraw will not draw inverted DIBs.
lpBits
Pointer to the buffer that contains the bitmap bits.
xSrc
The x-coordinate, in pixels, of the upper left corner of the source rectangle. The coordinates (0,0) represent the upper left corner of the bitmap.
ySrc
The y-coordinate, in pixels, of the upper left corner of the source rectangle. The coordinates (0,0) represent the upper left corner of the bitmap.
dxSrc
Width, in pixels, of the source rectangle.
dySrc
Height, in pixels, of the source rectangle.
wFlags
Applicable flags for drawing. The following values are defined.
| Value | Meaning |
|---|---|
| DDF_BACKGROUNDPAL | Realizes the palette used for drawing in the background, leaving the actual palette used for display unchanged. This value is valid only if DDF_SAME_HDC is not set. |
| DDF_DONTDRAW | Current image is decompressed but not drawn. 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 the DrawDibBegin function, set this value in DrawDibBegin rather than in DrawDibDraw. |
| DDF_HURRYUP | Data does not have to be drawn (that is, it can be dropped) and DDF_UPDATE will not be used to recall this information. DrawDib checks this value only if it is required to build the next frame; otherwise, the value is ignored.This value is usually used to synchronize video and audio. When synchronizing data, applications should send the image with this value in case the driver needs to buffer the frame to decompress subsequent frames. |
| DDF_NOTKEYFRAME | DIB data is not a key frame. |
| DDF_SAME_HDC | Use the current DC handle and the palette currently associated with the DC. |
| DDF_SAME_DRAW | Use the current drawing parameters for DrawDibDraw. Use this value only if lpbi, dxDst, dyDst, dxSrc, and dySrc have not changed since using DrawDibDraw or DrawDibBegin. DrawDibDraw typically checks the parameters, and if they have changed, DrawDibBegin prepares the DrawDib DC for drawing. This flag supersedes the DDF_SAME_DIB and DDF_SAME_SIZE flags. |
| DDF_UPDATE | Last buffered bitmap is 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
DDF_DONTDRAW causes DrawDibDraw to decompress but not display an image. A subsequent call to DrawDibDraw specifying DDF_UPDATE displays the image.
If the DrawDib DC does not have an off-screen buffer specified, specifying DDF_DONTDRAW causes the frame to be drawn to the screen immediately. Subsequent calls to DrawDibDraw specifying DDF_UPDATE fail.
Although they are set at different times, DDF_UPDATE and DDF_DONTDRAW can be used together to create composite images off-screen. When the off-screen image is complete, you can display the image by calling DrawDibDraw.
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 |