We proceed to the three-dimensional modelling with the sketch which has been approved and agreed already – making modifications in the strict mathematical three-dimensional model is a much more time-consuming task than consideration of options, adjusting a couple of lines in the sketch.
Therefore, as a rule, at the stage of three-dimensional modelling, the work is conducted on one model (without variations), and is presented iteratively for the client for assessment.
As soon as the primary three-dimensional model is finished, it becomes possible to proceed to objects that are more physical than drawing a picture – photo-realistic visualization and prototyping on a 3D printer.