display-sub - Make a child visual that is a window to the parent
Creates a "child" visual within a "parent". This can be thought of as a
window and the display-sub target is intended for simple windowing
No textual arguments, since this target can only be used by
applications. argptr must contain the parent visual.
The sub target behaves a bit special with respect to (i.e. abuses the
semantics of :) the ggiSetMode(3) call. It uses the "visible" size for
the top left corner position of the window within the visual, and the
"virtual" size for window width and height. Note, that moving/resizing
the window does not cause any drawing action. You have to perform
those yourself. All it does for you is providing a virtual visual
within an existing one, which is convenient to allow for window system
canvases to be about any GGI program.
Important: It is possible to have (0, 0) as upper, left corner.
But beware, 0 means GGI_AUTO and therefore it may get overridden
by GGI_DEFMODE environment variable. In this case, you may get
Specifies the target which to draw on (the parent target). This
defaults to automatic selection (just like using ggiOpen(NULL)
when GGI_DISPLAY is not set).
· DirectBuffer not supported.
· Accelerated to the point of the parent. Calls are mapped through
with modified clipping and coordinates.