The muscle force distribution diagram is a geometric diagram. You can find further information concerning the mathematical background in the chapter about geometric models. The following picture shows a short overview of the specific parts of the diagram:

 

The additional information states the active model as well as the displayed elevation plane and the appropriate eye with its muscles, which the diagram currently comprises. Within the diagram the adduction/abduction of the current gaze direction for the eye selected in the diagram is displayed in the form of a line. When you left-click on the line with the mouse and then move the mouse across the diagram while still pressing the mouse button, the gaze direction in adduction/abduction can be modified.