How Publisher Traps Publisher evaluates the publication for overlapping and adjoining color objects and text. Then it checks to see if any of the rules for not trapping objects apply.
Publisher can also trap differently over different backgrounds.
For example, if a text character overlaps dark, light, and similar-color backgrounds, Publisher traps each section of the character against each different background color using a spread, choke, or centerline trap as appropriate. When determining how to trap different parts of an object, Publisher traps borders first, then fills, and then text. To trap two different parts of the same object, such as a multicolor border, Publisher designates one color as the foreground color and the other as the background color. Publisher considers imported objects, gradients, and patterns to be indeterminate, and spreads colors that overlap those backgrounds. Publisher uses a separate default width to trap to indeterminate backgrounds.