The layout makes space for a legend if needed
prFpGetLayoutVP(lineheight, labels, nr, legend_layout = NULL)Height of the graph. By default this is auto and adjustes to the
space that is left after adjusting for x-axis size and legend. Sometimes
it might be desireable to set the line height to a certain height, for
instance if you have several forestplots you may want to standardize their
line height, then you set this variable to a certain height, note this should
be provided as a unit object. A good option
is to set the line height to unit(2, "cm"). A third option
is to set line height to "lines" and then you get 50 % more than what the
text height is as your line height
The labels
Number of rows
A legend layout object if applicable
viewport Returns the viewport needed