| Attribute | Default | InputOutput | InputOnly
|
|---|---|---|---|
| backing-store | NotUseful | Yes | No |
| backing-planes | Allones | Yes | No |
| backing-pixel | zero | Yes | No |
| save-under | False | Yes | No |
| event-mask | emptyset | Yes | Yes |
| do-not-propagate-mask | emptyset | Yes | Yes |
| override-redirect | False | Yes | Yes |
| colormap | CopyFromParent | Yes | No |
| cursor | None | Yes | Yes |
3.2.1. Background Attribute
Only InputOutput windows can have a background. You can set the background of an InputOutput window by using a pixel or a pixmap.
The background-pixmap attribute of a window specifies the pixmap to be used for a window's background. This pixmap can be of any size, although some sizes may be faster than others. The background-pixel attribute of a window specifies a pixel value used to paint a window's background in a single color.
You can set the background-pixmap to a pixmap, None (default), or ParentRelative. You can set the background-pixel of a window to any pixel value (no default). If you specify a background-pixel, it overrides either the default background-pixmap or any value you may have set in the background-pixmap. A pixmap of an undefined size that is filled with the background-pixel is used for the background. Range checking is not performed on the background pixel; it simply is truncated to the appropriate number of bits.
If you set the background-pixmap, it overrides the default. The background-pixmap and the window must have the same depth, or a BadMatch error results. If you set background-pixmap to None, the window has no defined background. If you set the background-pixmap to ParentRelative:
- The parent window's background-pixmap is used. The child window, however, must have the same depth as its parent, or a BadMatch error results.
- If the parent window has a background-pixmap of None, the window also has a background-pixmap of None.
- Acopy of the parent window's background-pixmap is not made. The parent's background-pixmap is examined each time the child window's background-pixmap is required.
- The background tile origin always aligns with the parent window's background tile origin. If the background-pixmap is not ParentRelative, the background tile origin is the child window's origin.
Setting a new background, whether by setting background-pixmap or background-pixel, overrides any previous background. The background-pixmap can be freed immediately if no further explicit reference is made to it (the X server will keep a copy to use when needed). If you later draw into the pixmap used for the background, what happens is undefined because the X implementation is free to make a copy of the pixmap or to use the same pixmap.
When no valid contents are available for regions of a window and either the regions are visible or the server is maintaining backing store, the server automatically tiles the regions with the window's background unless the window has a background of None. If the background is None, the
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