Sketching representation. We define a stroke Sas an ordered set
of pointsfs0,::,sn1g, which is drawn onto a drawing surface Ds
.
Each strokeSis stored as a parametric NURBS curve Nof degree
D¼3. The curveNis parameterized with t edit points, wheret
corresponds to the total number of joints that belong to the same
region Kof the 3D model (seeFig. 4). The number of knots
required is 2Dþt2 and all weights are equal to 1. In the current
version of the system, we do not take advantage of the weight
parameter to create the curve. The method generates the curveN
by choosing the edit pointsepi
along the total number of points,n,
of the original strokeS: