Color treated as transparent

WTSupported in traditional Synergy on Windows




The SYN_TRANSPARENT_COLOR environment variable specifies a color to be treated as transparent. It is ignored on Windows 8 and higher.


The RGB triplet for the color you want to designate as transparent. This triplet must be in hexadecimal notation, separated by commas and preceded by “0x”, as follows:


where rr is the value for red, gg is the value for green, and bb is the value for blue.


Only one color can be designated as transparent, and the specified color will be transparent in all images that contain it. Transparent means that pixels that correspond to that color be left unpainted, so that they show whatever color was painted at that location “behind” the image (for example, the face color on a button, or whatever else may have been printed in the same location on a page by the Synergy Windows printing API). This feature accommodates for the fact that not all users use the same background colors for toolbar and other buttons.

If SYN_TRANSPARENT_COLOR is not set, or if it is not set correctly, transparency will not be imposed on any images.


You can only use the SETLOG routine to set the value of SYN_TRANSPARENT_COLOR before loading the first image. After the first image is loaded, you cannot use SETLOG.

Setting location

The environment or the [synergy], [dbr], or [myprog] section of synergy.ini (where myprog is any .dbr file).

Used by

UI Toolkit, Composer, Synergy Windows printing API


In the synergy.ini file,