In order to specify the properties, restraints and loads associated with joints and members, it is necessary to be able to identify which parts of the structure the various properties will be associated with.

You do this by graphically selecting joints and members prior to choosing menu commands.  When you choose a command from a menu, to apply restraints at joints for example, the command will act on the joints that are currently selected.  Note that you cannot select a joint or member that has been hidden using the clipping or masking commands.

To select a joint

§    Click on the joint

A selected joint is indicated by a solid black box around the joint.

To select a group of joints

§    Drag a rectangle which encloses the joints to be selected

To select all the joints

§    Choose All from the Select menu

§    Click the OK button

To extend or reduce the selection

§    Shift-click to add a joint to or remove a joint from the current selection

§    Shift-drag to add a group of joints to or remove a group of joints from the current selection

If you know the number of the joint you wish to select, you can select it using the Joints command from the Select menu.

If more than one joint lies under the point where you click, Multiframe will select the joint closest to you.

To select a member

§    Click on the member away from its ends

A selected member is drawn with a heavy black line.  A selected member always has the two joints at its ends selected.

If you know the number of the member you wish to select, you can select it using the Members command from the Select menu.

To select a group of members

§    Drag a rectangle which encloses the members to be selected

If you drag from top-left to bottom-right, all of the members enclosed will be selected. If you drag from bottom-right to top-left, all of the enclosed members and all of the members intersecting with the rectangle will be selected.

To select all the members

§    Choose All from Select menu

To extend or reduce the selection

§    Shift-click to add a member to or remove a member from the current selection.

§    Shift-drag to add a group of members to or remove a group of members from the current selection

When performing a drag selection there are two techniques for selecting a group of members and joints. The first is by using a rectangular box as described above.

An alternative to this is to use a line selection in which the user drags the end of a straight line across the screen. In this case all members that intersect this line are selected and well as all joints connected to these members.

The selection tool to be used when performing a drag selection is picked using the View Toolbar. Clicking on the dotted square or dotted line buttons chooses the corresponding selection tool.