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.
C++ Syntax
typedef struct {
UINT32燢ey;
INT16燞mf;
PWMFRect16燘oundingBox;
INT16營nch;
UINT32燫eserved;
INT16燙hecksum;
} WmfPlaceableFileHeader;
FreeBASIC 语法
TYPE WmfPlaceableFileHeader
Key AS UINT32
Hmf AS INT16
BoundingBox AS PWMFRect16
Inch AS INT16
Reserved AS UINT32
Checksum AS INT16
END TYPE
成员
Key
Identification value that indicates the presence of a placeable metafile header. This value is always &H9AC6CDD7.
Hmf
Handle to the metafile in memory. When written to disk, this field is not used and will always contains the value 0.
BoundingBox
Destination rectangle, measured in twips, for displaying the metafile.
Inch
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
Not used and is always set to 0.
Checksum
Checksum for the previous 10 WORDs in the header. This value can be used to determine whether the metafile has become corrupted.
备注
Although placeable metafiles are quite common, they are not directly supported by the Microsoft Windows application programming interface (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.