This tries to mimic the old renderer's behavior as closely as possible.
In the absence of any information, DPI is assumed to be 96x96. DPI can
be configured on a per-bar basis using the configuration key "dpi".
To use the DPI configuration from Xresources (if built with support),
one can specify the following in the bar config:
dpi = ${xrdb:Xft.dpi:96}