Function load 

pub(super) fn load<'a, 's, 'buf, S: Scale>(
    plan: &'s OutlinePlan<'a>,
    context: &'a dyn OutlineContext<'a>,
    scale: &'s S,
    buffers: Buffers<'buf, S>,
    hinter: Option<&mut dyn Hinter<S::Coord>>,
) -> Result<OutlineRef<'buf, S::Coord>, Error>

Builds the outline a plan describes.

The method on OutlinePlan is the entry point; this is where the work lives, alongside the pass that does it.