Printer Marks are special pieces of information located outside of the actual print result. They are used to prove the correctness of the result in prepress printing. They are placed outside the TrimBox (More information about the PDF page boxes can be found in chapter PDF Page Boxes).

Cutting out the print result of the print sheet is done inside the bleed area. Trim and bleed marks indicate where this area starts and ends. Both types of marks are displayed as hairlines in the corner of the print sheet. Registration marks show whether the printer's colors are aligned properly. They are printed as crosshair-shaped objects located on each side of the print sheet.

Color bars show if the colors of the print result meet the expected result. They consist of a variety of colors that can be checked individually.

The property "-ro-marks" is used to add trim, bleed and registration marks. One or multiple of the following values can be set to add the corresponding marks to the document:

Example: Setting printer marks

-ro-marks: trim bleed registration;
-ro-marks-width: 1pt;
-ro-marks-color: red;

The property "-ro-marks-width" sets the width of the mark lines, "-ro-marks-color" sets their color.

Setting one of the following properties defines where a color bar is added to the document:

Allowed values for these properties are single or multiple colors which will be sequentially painted from left to right or from top to bottom respectively. The following two values that each provide a distinctive set of colors, are supported for colorbars:

Example: Setting color bars.

-ro-colorbar-bottom-left: gradient-tint;
-ro-colorbar-bottom-right: progressive-color;