OBJPROP_BACK...explanation...

 
Can someone please explain this object property to me? Thanks to Phy, i know that I can use it to display/not display the info tag on a vertical line. Why does it block display of the tag and not the vertical line? What else does it do? How else can it be used? Searching the web has not provided any detailed information. Nor does the documentation...at least not to the point where I comprehend its usage.
 

OBJPROP_BACK sets the object as background or foreground... it fills rectangles and triangles and ellipses or leaves only an outline.

Play with it and see.

 
Ray:

OBJPROP_BACK sets the object as background or foreground... it fills rectangles and triangles and ellipses or leaves only an outline.

Play with it and see.

Thank You @Ray
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