'qflp' RETURN 'w'|'e'|'s'|'a'|'i'|'q'This keyword is used to invert the outer- and inner side (the orientation) of shell-elements and surfaces. The orientation of shell-elements or surfaces can be seen by the interior color. The outer face reflects light, if the face is dark-grey it is the back-side. If ''Toggle Culling Back/Front'' was selected before then both sides are illuminated. To flip the orientation of a surface and all related shell-elements select either a shell-element with the ''e'' key or if the illuminated surfaces are displayed (see ``rep'' how to do that) select the surface with the ''s'' key. If only elements are in the database flip them with the ''e'' key. Choose all in range with the ''a'' key or individuals with the ''i'' key before. Press ''q'' to quit the command.
It is also possible to measure distances between two pixels on the screen. Just press the key ''w'' on the positions of the two pixels. The distance is calculated in the scale of the displayed geometry.