(Note: The term “display” for the purposes of this manual means the area of
the computer screen controlled by nu/TPU. For ASCII terminals and MS-DOS, the
nu/TPU display area is the entire screen. For Motif and MS Windows or other
window applications, the display is the area inside the window in which nu/TPU is
executed.)
nu/TPU’s window manager controls all output to the user display. The window
manager is invoked when either the UPDATE or REFRESH built-in is called, or
control is passed to nu/TPU’s main processing loop. The main processing loop is
reached only after all user-defined procedures have completed execution. The major
functions included in the window manager are listed and detailed below.
A nu/TPU screen can range in size from 1x1 character to 2(32-1) -1 characters
wide and 2(32-1) -1 lines long. Each nu/TPU window can have an optional status
line. Every window must be at least one line long, two lines if the status line
is included. The number of possible visible windows is equal to the number of
display lines. It is not possible to split windows vertically in any fashion.
Text scrolling is allowed in both the vertical and horizontal direction.
Vertical scrolling is done automatically in the window manager if previous calls to
user procedure or built-in functions move the current editing position outside
of the current window. Horizontal scrolling is managed through the SHIFT
built-in. Normally horizontal scrolling is not done automatically, but can be
programmed as an extension by the user.
Cursor motion has two attributes: SOUND/FREE and CROSS_WINDOW_ BOUNDS. FREE
cursor movement allows the cursor to be moved anywhere in the current window
regardless of whether any text exists at that screen location, including beyond the
end of line, end of buffer, before the left margin, and into the middle of a
tab. These positions are not possible if the cursor is BOUND. If there is no
text at the cursor position, the text being edited is padded with spaces to create
a position to match the current cursor position. When the second attribute,
CROSS_WINDOW_ BOUNDS, is set to ON, the cursor can move from one window to
another when a window boundary is reached. Normal operation is to scroll the text
when a window boundary is reached and not jump to the next window.
nu/TPU supports color and the attributes: normal, bold, blink, reverse, and
underline. All of these are not available for all computers. For the definitive
set of attributes available, please review your site documentation.
For details on mouse support, please review your hardware specific
documentation or the on-line help text. Generally, mice can provide powerful alternative
accelerators to standard functions along with the ability to cut and paste text
to and from other application windows. Text positioning, command line actions,
cursor movement, text selection, and other operations can all be accomplished
with the mouse.
Windows are created by CREATE_WINDOW, altered by ADJUST_ WINDOW, and removed
by the built-in DELETE. Please review the appropriate built-in functions for
complete details. Windows, when created or adjusted, may overlap existing windows.
The current window is always fully visible. When a window is completely
covered by other windows, it is said to be occluded. A buffer may have multiple
windows mapped to it, but each window can only be mapped to a single buffer. A
window cannot display text until it has been mapped to a buffer with the built-in
MAP.
Screen Management
Splitting the display horizontally into 2 or more windows
Text scrolling in vertical and horizontal directions
Cursor motion
Character attributes: normal, bold, blink, reverse, and underline
Color definitions
Mouse, pull-down and pop-up menus, and scroll bar support