L_GetBitmapAlpha

#include "l_bitmap.h"

L_LTKRN_API L_INT L_GetBitmapAlpha(pBitmap, pAlpha, uStructSize)

pBITMAPHANDLE pBitmap;	points to the source bitmap handle
pBITMAPHANDLE pAlpha;	points to the destination bitmap handle
L_UINT uStructSize;	size in bytes, of the structure pointed to by pAlpha

Creates a grayscale bitmap from the source bitmap's alpha channel data.

Parameter	Description
pBitmap	Points to the source bitmap handle.
pAlpha	Points to the destination bitmap handle to hold the alpha channel data.
uStructSize	Size in bytes, of the structure pointed to by pAlpha, for versioning. Use sizeof(BITMAPHANDLE).

Returns

SUCCESS	The function was successful.
< 1	An error occurred. Refer to Return Codes.

Comments

This function does not support signed data images. It returns the error code ERROR_SIGNED_DATA_NOT_SUPPORTED if a signed data image is passed to this function.

Only 16-, 32-, and 64-bit images can have an alpha channel. If the source bitmap has another color resolution, the result is an image filled with zeros.

Functions:	L_SetBitmapAlpha, L_CreateMaskFromBitmapRgn, L_SetBitmapRgnFromMask, L_BitmapHasMeaningfulAlpha
Topics:	Defining and Using a Bitmap Region
	Color Halftone and Halftone Images
	Saving a Region

L_GetBitmapAlpha

Returns

Comments

Example