Make a child visual that is a window to the parent

Name

display-sub : Make a child visual that is a window to the parent

Synopsis

display-sub

Description

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 systems.

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. So, to specify (0, 0) as upper, left corner, say (-1, -1) instead, otherwise you may get unintended results.

Options

No textual arguments, since this target can only be used by applications. argptr must contain the parent visual.

Features

  • DirectBuffer not supported.
  • Accelerated to the point of the parent. Calls are mapped through with modified clipping and coordinates.