This is an extremely important concept in the field of automobile design, and it is also a necessary skill for automobile designers and A-side designers.
CAS refers to high-quality surface, and the so-called visual expression of surface quality is unsmooth, wrinkle-free and unreasonable discontinuity.
Mathematically speaking, CAS refers to a surface with G2 continuity between facets and curvature radius jump less than a certain value. G2 continuity is necessary, but the curvature jump is different for different car factories. Among them, the requirements of GM are relatively low, 0.05mm, followed by Toyota, 0.03mm, and BMW and Volkswagen have the highest requirements, reaching 0.02 mm.