This script facilitates some common image mark-up tasks by adding multiple guides automatically.
To use it, you open the "Guides" dialog and apply one of the available commands (fig. 1).
The "Find Center" command adds horizontal and vertical guides at the document center (fig. 2).
The "Golden Ratio" tool divides your image according to the divine section rule.
The "Rule of Thirds" is a bit simplified version of the previous algorithm.
The "Mark Margins" command creates four guides on each side of the document in order. You only have to specify the distance from each guide to the nearest edge.
The "Guides from Selection" command creates up to 4 guides based on the current selection (fig. 3).