A computer-aided, design system and method generates procedural code from a plurality of spreadsheet formulas which define the behavior of a parametric object. These spreadsheet formulas drive function calls to an API of the design system when initially drawing the parametric object within a user interface, and these function calls may be cached as procedural code. In subsequent re-drawings of same object, the procedural code may be executed with updated or changed attributes received from an input dialog box. Rather than converting, translating, and parsing the spreadsheet formulas each time an entry is changed, the procedural code may be optimized for execution and also be concealed from the user so that any proprietary information in the formulas and functions is kept secret.