| Allegro CL version 8.2 Unrevised from 8.1 to 8.2. 8.1 version |
A class of object similar to windows in that you can draw onto it but
it is never visible on the screen. Its contents, however, can be
copied onto a visible window using copy-stream-area. A bitmap-window
(or
bitmap-pane
)
has the functionality of a bitmap-stream hardwired into it,
implementing the backing-store for automatically refreshing and
redisplaying the window. Bitmap-stream is provided in case you want to
manage the drawings stored in memory independently. For an example
using bitmap-streams, choose the Help menu | CG Examples and look for
Bitmap-streams: custom backing store.
One creates a bitmap-stream by calling open-stream, passing the desired
size as the value of page-width and
page-height keyword arguments. Below is an
example expression that creates a bitmap-stream; the two nil
arguments are required due to the two deprecated
optional parameters of open-stream.
(open-stream 'bitmap-stream nil nil :page-width 600 :page-height 400 :background-color yellow)
A diagram of window and widget classes is shown in Widget and window classes in cgide.htm.
Copyright (c) 1998-2016, Franz Inc. Oakland, CA., USA. All rights reserved.
This page was not revised from the 8.1 page.
Created 2010.1.21.
| Allegro CL version 8.2 Unrevised from 8.1 to 8.2. 8.1 version |