WmfPlaceableFileHeader structure (gdiplusmetaheader.h)
The WmfPlaceableFileHeader structure defines the fields of a placeable metafile header. Placeable metafiles were created as a way of specifying how a metafile is mapped and scaled on a display device.
Syntax
typedef struct {
UINT32 Key;
INT16 Hmf;
PWMFRect16 BoundingBox;
INT16 Inch;
UINT32 Reserved;
INT16 Checksum;
} WmfPlaceableFileHeader;
Members
Key
Type: UINT32
Identification value that indicates the presence of a placeable metafile header. This value is always 0x9AC6CDD7.
Hmf
Type: INT16
Handle to the metafile in memory. When written to disk, this field is not used and will always contains the value 0.
BoundingBox
Type: PWMFRect16
Destination rectangle, measured in twips, for displaying the metafile.
Inch
Type: INT16
Number of twips per inch used to represent the image.
Normally, there are 1440 twips per inch; however, this number can be changed to scale the image.
- A value of 720 specifies that the image is twice its normal size.
- A value of 360 specifies that the image is four times its normal size.
- A value of 2880 specifies that the image is half its normal size.
Reserved
Type: UINT32
Not used and is always set to 0.
Checksum
Type: INT16
Checksum for the previous 10 WORDs in the header. This value can be used to determine whether the metafile has become corrupted.
Remarks
Although placeable metafiles are quite common, they are not directly supported by the Windows API. To display a placeable metafile using the Windows API, you must first strip the placeable metafile header from the file. This is typically performed by copying the metafile to a temporary file starting at file offset 22 (0x16). This is because each placeable metafile begins with a 22-byte header that is followed by a standard metafile.
Requirements
Requirement | Value |
---|---|
Minimum supported client | Windows XP, Windows 2000 Professional [desktop apps only] |
Minimum supported server | Windows 2000 Server [desktop apps only] |
Header | gdiplusmetaheader.h (include Gdiplus.h) |