The default highlight pen has a COLORREF value of 0xFFFFFF (white). This color will not work well with images that have many mid-range gray colors. A better selection for such cases would be 0xC0C0C0 (silver).
When working with automated annotations, change the color of the pen that is used for highlighting and selecting by calling L_AnnSetAutoHilightPen for that automation object. Each automation object can have its own highlight pen color. To change the default highlight pen for newly created automation objects, call L_AnnSetAutoHilightPen and pass NULL for the hAutomation parameter.
To change the highlight color back to the default color after changing the highlight color, you must call L_AnnSetAutoHilightPen and use a COLORREF value of 0xFFFFFF.
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