This setting is an integer expression, specifying the number of additional decimals of precision that the formula needs. By default, Ultra Fractal uses enough decimals for the current zooming level, but your formula might require additional precision.
Together with the Additional Precision setting in the Formula tab of the Layer Properties tool window, the maximum value of the precision settings of all formulas in use is added to the default precision level to obtain the final number of decimals that is used for fractal calculations. This number can be verified in the Statistics tool window.
The expression must only use constant values, including the values of parameters and most predefined symbols. It is re-evaluated every time a parameter changes, or when one or more of the predefined symbols are changed.
The precision setting can be used in the default section of all types of formulas.
This is a snippet taken from the 3D Mapping transformation. This transformation has its own independent magnification parameter (Fractal Magnification), so it needs additional decimals of precision depending on the current value of Fractal Magnification. This is exactly what the precision setting is for.
default: precision = round(log(@fracmagn) / log(10)) float param fracmagn caption = "Fractal Magnification" default = #magn endparam