DRAWING VIEWPORT Action Control

        

This command allows the user to alternate between single and multiple viewport mode, and to specify which viewport is to be the active viewport. There is also a facility for copying drawings from one viewport to another.

Action Control Comments

USE vp The specified viewport vp becomes the active viewport. If going from single to multiple viewport mode, the current picture is automatically redrawn in the new viewport. If going from one multi-viewport to another empty multi-viewport then the current picture is not automatically redrawn although all necessary information will have been copied to the new viewport and the picture may be displayed by issuing any command that initiates a redraw. If returning to single viewport mode the picture that previously existed in that viewport will be redrawn.

COPY vp1 TO vp2 The drawing from previously used viewport vp1 is copied to viewport vp2. Viewport vp2 becomes the active viewport.

SETUP TWO-HORIZ The required multiple viewport configuration is

TWO-VERT specified. Note that THREE-HORIZ and

THREE-HORIZ THREE-VERT specify configurations comprising one

THREE-VERT half-screen and two quarter-screen viewports where

FOUR the half-screen viewport is horizontal or vertical respectively. (See note 3)

A viewport is specified either by a number from zero to four, or by a name as follows:

Viewport Description

FULL or 0 The full screen in single viewport mode.

TLEFT or 1 The top left quarter of the screen in multiple viewport mode.

TRIGHT or 2 The top right quarter of the screen in multiple viewport mode.

BLEFT or 3 The bottom left quarter of the screen in multiple viewport mode.

BRIGHT or 4 The bottom right quarter of the screen in multiple viewport mode.

If the current multiple viewport configuration does not contain the requested viewport then the most appropriate viewport will be selected. For example, if the current configuration is TWO-HORIZ (two horizontal viewports), then the viewport requests TLEFT (top left) and TRIGHT (top right) will both select the top horizontal viewport.

Notes:

1.

Hardware requirements
The multiple viewport facility is only supported on graphics terminals that have an acceptable resolution. In the multiple viewport mode of operation on lower resolution graphics devices it may not be possible to display certain pictures which contain predominately alphanumeric text. In these cases a warning will be issued.

2.

Changes to the database in multiple viewport mode
Only the current view information is retained for a viewport when a new viewport is selected. All the viewports access the same database for any particular model and any changes to this database will effect all the viewports working with that model. However, the display in any viewport will only change when a command accessing the database is issued in that viewport.

For example, in FEMGEN, if only points are present in viewport 1 and lines are then added in viewport 2, on return to viewport 1 VIEW GEOMETRY ALL will show lines and points. In FEMVIEW, deletion or creation of loadcases will effect all the viewports using that model.

 

Figure 2.59: Using Four Viewports

 

Figure 2.60: Using Two Horizontal Viewports

3.

Changing multiple viewport configurations
It is possible to change the multiple viewport configuration when already in multi-viewport mode. The rule is that viewport 1 in the existing configuration will become viewport 1 in the new configuration, viewport 2 will become viewport 2, etc. If the new configuration has fewer viewports than the existing configuration then the pictures in the viewports unsupported by the new configuration will be lost.

It is not possible to change the multiple viewport configuration if this would result in the active viewport being lost.