| Unit | U | Unit of dimensions. If a unit is given, and nothing else is passed in, then a default design data is constructed.
Millimeters = 0,
Centimeters = 1,
Decimeters = 2,
Meters = 3,
Inches = 4,
Default is Centimeters. | Text |
| Max Riser Height | R | Maximum allowable riser height for the stairs. | Number |
| Min Tread Width | T | Minimum required tread width for the stairs. | Number |
| Shortest Tread Edge Length | S | Minimum allowable tread width at the edges of each tread. | Number |
| Formula Lower Limit | L | Change the lower limit of the function: "2a + b". | Number |
| Correction Count | C | Number of correction loops to perform. | Number |
| Ignore Formula | F | Ignore Formula | Boolean |
| Allow Changing Curve | A | If it is allowed to extend or trim curves when necessary. | Boolean |