The GetObject function obtains information about a specified graphics object. Depending on the graphics object, the function places a filled-in BITMAP, DIBSECTION, EXTLOGPEN, LOGBRUSH, LOGFONT, or LOGPEN structure, or a count of table entries (for a logical palette), into a specified buffer.
int GetObject(
HGDIOBJ hgdiobj, |
// handle to graphics object of interest |
int cbBuffer, |
// size of buffer for object information |
LPVOID lpvObject |
// pointer to buffer for object information |
); |
The following table shows the type of information the buffer receives for each type of graphics object you can specify with hgdiobj:
hgdiobj Type |
Data Written to *lpvObject |
HBITMAP | |
HBITMAP returned from a call to CreateDIBSection |
DIBSECTION, if cbBuffer is set to sizeof(DIBSECTION), or BITMAP, if cbBuffer is set to sizeof(BITMAP) |
HPALETTE |
a WORD count of the number of entries in the logical palette |
HPEN returned from a call to ExtCreatePen | |
HPEN | |
HBRUSH | |
HFONT |
If the lpvObject parameter is NULL, the function return value is the number of bytes required to store the information it writes to the buffer for the specified graphics object.
If the function succeeds, and lpvObject is a valid pointer, the return value is the number of bytes stored into the buffer.
If the function succeeds, and lpvObject is NULL, the return value is the number of bytes required to hold the information the function would store into the buffer.
If the function fails, the return value is zero. To get extended error information, call GetLastError.
The buffer pointed to by the lpvObject parameter must be sufficiently large to receive the information about the graphics object.
If hgdiobj identifies a bitmap created by calling CreateDIBSection, and the specified buffer is large enough, the GetObject function returns a DIBSECTION structure. In addition, the bmBits member of the BITMAP structure contained within the DIBSECTION will contain a pointer to the bitmap’s bit values.
If hgdiobj identifies a bitmap created by any other means, GetObject returns only the width, height, and color format information of the bitmap. You can obtain the bitmap’s bit values by calling the GetDIBits or GetBitmapBits function.
If hgdiobj identifies a logical palette, GetObject retrieves a two-byte integer that specifies the number of entries in the palette. The function does not retrieve the LOGPALETTE structure defining the palette. To retrieve information about palette entries, an application can call the GetPaletteEntries function.
CreateDIBSection, GetBitmapBits, GetDIBits, GetPaletteEntries, GetRegionData, BITMAP, DIBSECTION, EXTLOGPEN, LOGBRUSH, LOGFONT, LOGPALETTE, LOGPEN
See: