:arc-mode, :background, :cap-style,
:clip-mask, :clip-ordering, :clip-x,
:clip-y, :dashes, :dash-offset,
:exposures, :fill-rule, :fill-style,
:font, :foreground, :function,
:join-style, :line-style, :line-width,
:plane-mask, :stipple, :subwindow-mode,
:tile, :ts-x, :ts-y
These keyword arguments and associated values specify which
graphics context components are to be changed. Any components
not specified are left unmodified. See paragraph 5.2,
Creating Graphics Contexts, for more information.
The body of code which will have access to the altered
Changes the indicated graphics context components to the
specified values only within the dynamic extent of the body.
with-gcontext works on a per-process basis in a
multiprocessing environment. The body is not surrounded
with-display form. If there is no local cache for the
specified graphics context, or if some of the component states
with-gcontext does the save and restore by creating a
temporary graphics context and copying components to and from
it using copy-gcontext-components.