Edit Bar controls: Accept, Rewind, Variables, Construction Lines, Show Dimensions
This tool allows you to take a fully or partially dimensioned design and modify the dimension values, thus modifying the design geometry itself. In addition, by making use of variables, you can modify the design by changing the values of the variables.
Such a dimensioned design, created for the purpose of re-dimensioning, is referred to as a parametric design.
Before activating the Re-dimension tool, you should ensure that the design contains dimensions on all geometry which you may wish to parametrically modify. Additionally, you should ensure that the geometry is not over-constrained by the dimensions (that is, containing redundant dimensions). On activating the tool, if the drawing is over-dimensioned, you are warned that there are too many dimensions and the superfluous dimensions are highlighted in white.
If the drawing is suitable, that is if no warning messages appear, a progress indicator appears showing that the drawing is being parameterized. The cursor is then displayed as 'entity'. You can now proceed with parametrically modifying the design. This can be done in two ways:
- by directly choosing dimensions and modifying the values - click on the dimension you wish to modify and enter the new value in the Dimension Value spin box on the Edit Bar.
- by changing the values of variables which have been associated with dimensions.
The modifications you make do not take effect immediately. Once you have made all the required changes, you should press the Accept 
button on the Edit Bar. The geometry is then recalculated, according to the changes you have requested, and redisplayed.
If you have used variables with dependencies, you will notice the dependency code being compiled. If errors in this code are detected, you must correct them.
If you are happy with the changes to the design, you should press the right mouse button to cancel the tool; if not then further changes can be made in the same way. Using the Rewind 
button cancels the dimensions you modified in reverse order.
For a summary of the other options on the Edit Bar, see How the Re-dimension Tool Works, below.
Modifying Parametric Variables
To create a parametric design controlled by variables, you must use the tools described in the following sections Global Variables and Associate Variables With Dimensions.
When you activate the Re-dimension tool, pressing the button Variables on the Edit Bar causes the Change Variables Values dialog to appear. All variables, with their values, are shown here except those variables which have dependencies.
NOTE: Even if a variable is not used at all in the design, it is still displayed in the dialog box.
You can change any of the values displayed. When you have made your changes, press OK and then press the Accept button on the Edit Bar. The design is updated according to the new values of the variables.
How the Re-dimension Tool Works
From an arbitrary starting point, the tool checks each entity in the design in turn. A temporary construction line is added (if none is already present) to determine the entity's location with respect to other entities in the design.
If there are insufficient dimensions determining the length and orientation (unless it is a horizontal or vertical line) then temporary dimensions are added. If the entity was already on a temporary construction line then fewer new dimensions are required.
This process continues until all entities have been checked. By the end, all entities lie on a construction line and are constrained by dimensions. You can view these constructs by using the options on the Edit Bar:
- Construction Lines
- Show Dimensions
NOTE: These temporary entities are automatically removed as soon as the Re-dimension tool is cancelled.
A design may be over-constrained if you have dimensioned an entity which is already sufficiently constrained by construction lines created when processing other entities. For example, if your design is a box where two of the bottom flaps are of the same size and same position vertically, then you only need to add a vertical dimension to one of the flaps. The horizontal lines in the other flap are constrained by the same vertical dimension.
NOTE: Relocating the drawing origin may alter the behaviour of the tool.