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INVERTEDTEXTCALLBACK

Summary

Handles each inverted text segment found by L_InvertedTextBitmap.

Syntax

#include "l_bitmap.h"

L_INT pEXT_CALLBACK YourFunction(hRgn, pBoundingRect, iWhiteCount, iBlackCount, pUserData)

Parameters

HRGN hRgn

Windows region representing the inverted text to be removed. It is the programmers responsibility to delete this region (using DeleteObject()) when it is no longer needed.

PRECT pBoundingRect

Pointer to a RECT structure that contains the bounding rectangle of the inverted text region being processed.

L_INT iWhiteCount

Total number of white pixels in the inverted text region being processed.

L_INT iBlackCount

Total number of black pixels in the inverted text region being processed.

L_VOID *pUserData

A void pointer that you can use to access a variable or structure containing data that your callback function needs. This gives you a way to receive data indirectly from the function that uses this callback function. (This is the same pointer that you pass in the pUserData parameter of L_InvertedTextBitmap.)

Keep in mind that this is a void pointer, which must be cast to the appropriate data type within your callback function.

Returns

Value	Meaning
SUCCESS_REMOVE	Invert the text.
SUCCESS_NOREMOVE	Do not invert the text.
Otherwise	An error occurred. Refer to Return Codes.

Comments

The callback is called once for each area of inverted text that is detected. Return SUCCESS_REMOVE to have the area modified. Return SUCCESS_NOREMOVE to leave the area unchanged. Pass any other value to abort. This value will be the return value of the L_InvertedTextBitmap() . If flags INVERTEDTEXT_IMAGE_UNCHANGED and INVERTEDTEXT _SINGLE_REGION are being used, then the return value of the callback affects only the internal single region that contains all the changes.