ImageGear for C and C++ on Linux v20.0 - Updated
API Reference Guide > ART Component API Reference > ART Component Functions Reference > GUI Functions > ART_GUI_mark_hit_test

This function returns all mark indexes that are within the rectangle specified by lpRect.


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AT_ERRCOUNT ART_GUI_mark_hit_test(
        HIGEAR hIGear, 
        HWND hWnd,  
        DWORD dwGrpID, 
        const LPAT_RECT lpRect, 
        LPART_MARK_INDEX lpMarkIndex, 
        DWORD dwMarkCount, 
        LPDWORD lpMarkCount, 
        LPAT_MODE lpResizeBox, 
        LPDWORD lpBoxIndex


Name Type Description
hIGear HIGEAR HIGEAR handle to the image.
hWnd HWND HWND handle to the window.
dwGrpID DWORD Identifier of group.
lpRect const LPAT_RECT Far pointer to an AT_RECT struct specifying the rectangular portion of image to search for marks.
lpMarkIndex LPART_MARK_INDEX A far pointer returning the indexes.
dwMarkCount DWORD The amount of memory available for returned marks.
lpMarkCount LPDWORD The number of marks actually returned.
lpResizeBox LPAT_MODE A far pointer to a defined constant of type AT_MODE, only used if the rectangle lpRect is an individual point and is over a resize handle.
lpBoxIndex LPDWORD A far pointer to the index of the resize handle, or NULL if the return value is not needed.

Return Value:

Returns the number of ImageGear errors that occurred during the function call.

Supported Raster Image Formats:

All pixel formats supported by ImageGear for C and C++.


Copy Code
HIGEAR hIGear; /* HIGEAR handle of */
/* image  */
AT_ERRCOUNT nErrcount; /* Tally of IG errors on */ 
/* stack  */
AT_RECT  MarkRect; /* Region of image to */
/* query  */
ART_MARK_INDEX MarkIndexes; /* Array of mark indexes */
DWORD MarkCount; /* Space available for */
/* marks or # of marks */
AT_MODE  lpResizeBox; /* Handle to resize box, */ 
/* if there is one  */
AT_DIMENSION nWidth, /* Original width and */
/* height  */
UINT nBpp; /* Bits per pixel  */
/* (not used)  */
AT_DIMENSION nHalfWidth, /* Will hold half the */
/* width  */
nHalfHeight; /* and half the height */
/* Set rectangle to half the size of the image, centered */
if ( IG_image_is_valid (hIGear) )
IG_image_dimensions_get ( &hIGear, &nWidth, &nHeight, 
&nBpp );
nHalfWidth = nWidth / 2; 
nHalfHeight = nHeight / 2;
MarkRect.left  = nHalfWidth / 2;
MarkRect.right = MarkRect.left + nHalfWidth - 1;  = nHalfHeight / 2;
MarkRect.bottom = + nHalfHeight - 1;
nErrcount = ART_GUI_mark_hit_test(hIGear, hWnd, 
dwGroupID, &MarkRect, 
&MarkIndexes, MarkCount, &MarkCount, &lpResizeBox, 


The rectangle represents screen coordinates.

There is some variation in what is returned:

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