Measure mode turns the mouse into the pointer used to indicate points for measuring angles and line lengths, defining paths, and setting up grids. You can select the type of measurement you want to make by toggling through the measurement types. You can toggle by either pressing the spacebar or continuing to press F7. Note that you are prompted for the point to pick in the lower left hand corner of the main VIS window.
The appearance of measurement objects is controlled by settings in the Edit/Setup/Draw/Measure dialog box. Options such as font size and type, automatic placement of the value, arrow size, and angle measurement direction are global settings that affect all measurement values. Measurement values that contain a distance component (i.e. distance and linear velocity) are also related to the setting of each individual movies scale. If no scale is set for a movie, all distance measurements are given in pixels.
Measurements in VIS are based upon the two-dimensional computer image obtained from the video. Camera angles and subject depth are NOT factored in, therefore care should be take when evaluating measurement values.