How to create a parametric design

Editor → Future Design (Ribbon tab) → Parametric (Ribbon bar) → The Parametric Design to edit (Left panel)

How to create and use a Parametric design:

Click on Parametric on the Future Design tab.
On the bottom left of the screen, select to add a Add road aligned design from the dropdown menu.
On the left panel a new Design is added. Select this design.
On the bottom right panel, click on 'Draw Area' and select the area for the design.
With the sliders on the 'Design' tab you can adjust the parameters of the design.
On the 'Plots' tab you can add or change the function types being used to fill the plots. These will appear also on the left side, under the design you just created.
To remove a function type, you can select the entry on the left side, and click on the 'Remove' button.
You can also change function speciffic parameters on the right side, when you have the function type selected under the design on the left panel.
On the 'Roads' tab you can adjust road speciffic parameters.
After setting up all the parameters, click on 'Generate' on the right panel, to draw the plan according to the set parameters.
Verify that the selections in the 3D world and the information in the pie chart look like the desired result. If not, tweak the parameters further.
Either apply the design to start a Test Run, click on Save to Current to construct the Design in the Current Situation, or save the design as a Measure.
Verify that the result is correct. If not, revert the application by clicking on 'Revert' and tweak the configuration further. Please note that this step is not possible when the design is saved to Current.

Save to current: a test run is not started. Instead it is applied to the Current Situation. This method is not easily reversed.
Tip: use the Polygon pick selection tool to draw the area for the design.

See also