When registered, this callback gets called when ART encounters a mark that it does not know how to draw.

Declaration:

typedef VOID (ACCUAPI *LPFNIG_ART_DRAWNOTIFYFUNC)(
        HIGEAR hIGear, 
        DWORD dwGrpID, 
        LPVOID lpPrivate, 
        HDC hDC, 
        AT_MODE nWhen, 
        ART_MARK_INDEX hMarkIndex, 
        const LPART_MARK_ATTRIBUTES lpMarkAttr, 
        const LPAT_RECT lprcClip, 
        const LPAT_RECT lprcBounds, 
        AT_MODE nOrientation
);

Arguments:

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++.

Example:

VOID ACCUAPI DRAWNOTIFYFUNC( 
        HIGEAR hIGear,  
        DWORD dwGrpID,  
        LPVOID lpPrivate,  
        HDC hDC,  
        AT_MODE nWhen,  
        ART_MARK_INDEX hMarkIndex,  
        const LPART_MARK_ATTRIBUTES lpMarkAttr,  
        const LPAT_RECT lprcClip,  
        const LPAT_RECT lprcBounds,  
        AT_MODE nOrientation 
        )
{
        HBRUSH hBrush;
        HBRUSH hOldBrush;
        AT_RGBQUAD color = lpMarkAttr->rgbColor1;
        AT_POINT ptPoints[2];
        ptPoints[0].x = lpMarkAttr->rcBounds.left;
        ptPoints[0].y = lpMarkAttr->rcBounds.top;
        ptPoints[1].x = lpMarkAttr->rcBounds.right;
        ptPoints[1].y = lpMarkAttr->rcBounds.bottom;
        IG_dspl_image_to_device(hIGear, dwGrpID, hWnd, hDC, ptPoints, 2);
        hBrush = CreateSolidBrush(RGB(color.rgbRed, color.rgbGreen , color.rgbBlue));
        hOldBrush = SelectObject(hDC, hBrush);
        Ellipse(hDC, ptPoints[0].x, ptPoints[0].y, ptPoints[1].x, ptPoints[1].y);
        SelectObject(hDC, hOldBrush);
        DeleteObject(hBrush);
}

Remarks:

The main purpose of this callback is for painting user-defined marks that the developer has created. This callback gets called twice each time the mark needs to be painted. On the first call, the nWhen parameter is set to ART_DISPLAY_PREPAINT. This indicates that the underlying image has not repainted itself yet. On the second call, nWhen is set to ART_DISPLAY_POSTPAINT. Any drawing that is done during the pre-paint phase is clobbered by the underlying image when it paints itself. The pre-paint phase is used to create clipping regions for optimized painting. The mark is drawn during the post-paint phase. The hMarkIndex parameter indicates that the mark needs to be painted and its attributes are passed in the lpMarkAttr parameter. If the mark has extra data in named blocks that is necessary during painting, the named blocks are queried by this function.

The lprcClip parameter is the current clipping rectangle. Any drawing that occurs outside this rectangle is clipped by the operating system. This parameter is passed to give the callback an opportunity to optimize its painting within the rectangle. The lprcBounds parameter is the rectangle of the current boundaries of the mark. This parameter differs from the rcBounds field in the ART_MARK_ATTRIBUTES structure. The rectangle in this parameter is scaled for the display and if the underlying image is rotated, then lprcBounds is rotated. The nOrientation parameter tells the callback how to orient the mark when drawn. Possible values include: IG_ROTATE_0, IG_ROTATE_90, IG_ROTATE_180 and IG_ROTATE_270.