This topic explains how the mouse is used to perform particular actions in the system.
It does not cover typical Windows mouse operations and you should refer to the Windows documentation regarding these.
The mouse operation topics covered are:
Object Selection
Mouse Wheel
Stopping Drawing
Exiting a Viewing Tool
Object Selection
When performing procedures which require you to identify point, line or polygon objects, reference lines, directions or distances, it is generally possible to select these items from within the graphics window by using the mouse in the following manner.
Snapping
Snapping is the act of positioning the cursor near an object in the graphics window and pressing the snap button to highlight or attach a rubber band to the object. If the required object is not located, continue to snap until successful.
The snap mouse button is the right hand button on a two button. (Unless the user has configured the mouse to swap the left and right buttons. In that case the snap button will be on the left.)
Before you can snap to an object, focus must be on an appropriate edit field in a dialog box which allows access to the graphics window. In other words the edit field prompt must be in a field which requires an object to be identified. Such fields are common throughout the system. An example is the Point Number field in the Delete Points dialog box.
Snapping to locate an object does not carry out the currently relevant action. It merely selects the object. For example, snapping to a point from the Delete Point dialog box selects the point but does not delete it.
Many dialog box edit fields allow the entry of multiple point identifiers, line numbers or polygon numbers to which an operation is to be carried out. Multiple object identifiers may be entered by snapping to the individual object while holding down the 'Ctrl' key on the keyboard.
Accepting
Accepting is the act of pressing the accept button after the required object has been selected by snapping. Accepting is the means by which you tell the system that the correct object has been located and that the currently relevant action should be carried out. For example, accepting a point which has been snapped to from the Delete Point dialog box will actually delete the point.
The accept mouse button is the left hand button on a two button. (Unless the user has configured the mouse to swap the left and right buttons. In that case the accept button will be on the right.)
Accepting without Snapping
You may use the accept mouse button to carry out an operation without first snapping to locate the required object. However, this can be dangerous particularly if there are objects close together. Accepting without snapping will find the nearest relevant object to the cursor and carry out the currently relevant action immediately. For example, pressing the accept button without first snapping to a point from the Delete Point dialog box will actually delete the nearest point to the cursor.
Multiple object identifiers may also entered by accepting without snapping by holding down the 'Ctrl' key on the keyboard and pressing the accept button.
Careful use of Accepting without snapping can however speed up operation when objects are suitably spaced on the screen and there is therefore little chance of identifying the wrong object.
Mouse Wheel
The mouse wheel may be used to zoom or pan in all LISCAD views.
To zoom in, roll the mouse wheel forward.
To zoom out, roll the mouse wheel back.
To pan, depress the mouse wheel and drag the mouse.
To Fit the view to the extents of the data, double click the middle mouse button (mouse wheel button).
Stopping Drawing
If the graphics window is being regenerated and you wish to cancel the drawing activity, simply press the Snap mouse button within the graphics window. Drawing will cease and control of operation is returned to the user. This is a particularly useful feature if for example you selected the Fit tool by mistake in a very large job.
Exiting a Viewing Tool
The viewing tools are available for selection and use at all times that you have access to the graphics window. You may therefore, while using a command, select a viewing tool to modify the view in the graphics window. The Zoom In, Zoom Out, Pan and Window tools remain active after performing the action. Once you have finished with one of these tools, it may be exited and operation returned to the previous command by pressing the Snap button.
Pop-up Menus
When the cursor is over the graphics window you can press the right hand button to bring up a pop-up menu to get access to windows display functions.
If an interactive dialog box is active that allows you to snap to objects using the right hand button, the pop-up menu can be accessed by holding down the Shift key while pressing the right hand button in the graphics window.