FILEOVERLAYCALLBACKDATA

The FILEOVERLAYCALLBACKDATA structure passed to the OVERLAYCALLBACK function contains information about the overlay image found in the file. Some members of this structure are for input some are for output as follows:

Note:

The LTFIL.H header file describes the entire FILEOVERLAYCALLBACKDATA structure.

 

Member

Data Type

Description

pszFilename

L_TCHAR L_FAR*

(input) String containing the name of the file containing the overlay bitmap.

nPageNumber

L_INT

(input) Page number of the requested overlay image. 

bInfo

L_BOOL

(input) Determines whether overlay image info or actual bitmap is needed as follows: 

 

 

Value

Meaning

 

 

TRUE

Only the information about the overlay image is needed. You must now in the nInfoWidth, nInfoHeight, nInfoXResolution and nInfoYResolution members of this structure.

 

 

FALSE

The actual overlay bitmap is needed. You must now load the overlay bitmap into the pLoadBitmap member of this structure.

nInfoWidth

L_INT

(output) Overlay image width in pixels. If the bInfo member of this structure is TRUE, you need to set this member to the overlay bitmap width, otherwise, ignore.

nInfoHeight

L_INT

(output) Overlay image height in pixels. If the bInfo member of this structure is TRUE, you need to set this member to the overlay bitmap height, otherwise, ignore.

nInfoXResolution

L_INT

(output) Overlay image horizontal resolution in pixels per inch. If the bInfo member of this structure is TRUE, you need to set this member to the overlay bitmap horizontal resolution, otherwise ignore.

nInfoYResolution

L_INT

(output) Overlay image vertical resolution in pixels per inch. If the bInfo member of this structure is TRUE, you need to set this member to the overlay bitmap vertical resolution, otherwise ignore.

pLoadBitmap

pBITMAPHANDLE

(output) Pointer to a BITMAPHANDLE structure into which the overlay bitmap will be loaded. If the bInfo member is FALSE, you need to load the overlay bitmap into this member. Otherwise ignore. You do not need to call L_FreeBitmap on this bitmap. LEADTOOLS will free it for you once its done overlaying it on the image.

Example

For an example, refer to the OVERLAYCALLBACK function.