Time-slider and Time-ruler

  There are also special kinds of sliders and rulers which can be time-dependent, i.e. dependent on the main time ruler of the manager menu (see 4.3.5.2), or - more generally - depend on any other variable. They are called function-slider or function-ruler and consist of an additional button on their left, named (see figure 4.9).

  
Figure 4.9: Function-slider and function-ruler

This button pops up a spline-editor (see 4.1.2.10) that offers to change the time-dependency function and to switch the dependency on and off. If the dependency is on, this button is drawn pressed down, and the slider/ruler changes its value by evaluating the spline with respect to the current value of the main time ruler.