Specifies one of the transfer mode that can be used with the ink property.
set the ink of graphic "Overlay" to clear
Use the clear keyword to turn an object black.
The ink property determines how an object colors combine with the colors of the pixels underneath the object to determine how the object color is displayed.
When the clear mode is used, each component of the color underneath the object (red, green, and blue) is lowered to be equal to black.
The clear mode can be used only on Unix and Windows systems. On Mac OS systems, objects whose ink property is set to this mode appear as though their ink were set to reverse.
A list of all transfer modes can be found in the transfer mode glossary page for easy reference.