The draw pixel flow path menu option will trace the downslope flow path from any pixel and display it over the current map according to the Control Colours set in the View Attributes form (default is yellow). This is a temporary display layer and will disappear when the display is refreshed. If a time-out error occurs the flow path will be illustrated in red and will terminate and the user will be advised of the problem pixels (usually related to a Hydraulic Control).
This tool is designed to help visualise how flow will travel over the DEM, to test the implementation of Hydraulic Controls and the effectiveness of flat and pit removal algorithms.