Random Seed

When a Random Seed parameter is selected in the parameters list, the following user interface is displayed:

Random Seed parameters can only be mapped to published index ports in the composition. As such, the minimum value they can represent is 0.

The Default Value text field lets you specify the initial value for the parameter.

The Maximum Value text field lets you specify an upper limit for the values generated by this parameter. For example, if the range is 0 to 1000, all random values generated by this parameter will be between the numbers 0 and 1000.

When the Quartz composition port has no upper bound, FxFactory will display a really large maximum value next to the text field (e.g. 4,294,967,295). This value is architecture-dependent. Do not specify a maximum value to tell FxFactory that the randomly generated values should fall in the entire range allowed by unsigned word-sized integers on the current architecture.

Dependent Parameters

When the user requests a new random seed, the values of all dependent parameters are randomized as well, with the restrictions outlined below.

  • Slider parameters: the random value is picked only within the range defined by the slider, ignoring what the absolute range may be.
  • Angle parameters: the random value is picked between 0° and 360°, unless the range of the angle has been further limited within that range. Although most angle parameters do not have a lower or upper bound, values below 0° or above 360° are never picked, due to the differences in which effects interpret angle values.
  • Point parameters: the random location is picked within the video frame only, unless the developer has further restricted the range within the frame. The randomized location never falls outside the frame. Currently, all other constraints set for the point parameter are ignored.

On-screen Control

Random seed parameters are available via on-screen UI in Final Cut Pro X and Motion 5. By default, a single button lets the user assign a new seed value. Users can hold down the Option key to edit the current value instead.