Method and apparatus for continuity based smoothing

A system comprising:

• a non-transitory storage medium having instructions of a computer aided design program stored thereon;
• and
• one or more data processing apparatus able to run the instructions of the computer aided design program to perform operations specified by the instructions of the computer aided design program to cause the one or more data processing apparatus to
• obtain a complex modelled surface comprising a control mesh of control vertices, which define multiple smooth surface patches of the complex modelled surface;
• receive input specifying at least a portion of the complex modelled surface to be smoothed;
• identify from the input at least three of the multiple smooth surface patches corresponding to the at least a portion of the complex modeled surface to be smoothed, wherein the at least three surface patches are defined by at least eight of the control vertices from the control mesh;
• smooth the at least a portion of the complex modeled surface based on continuity, wherein the instructions cause the one or more data processing apparatus to smooth the at least a portion of the complex modeled surface by causing the one or more data processing apparatus to
• determine a measure of continuity at an interface between each pair of adjoining surface patches from the at least three surface patches, and
• modify positions of at least a subset of the at least eight control vertices, thereby modifying the at least three surface patches, by targeting an overall improvement in the measures of continuity for the interfaces between the pairs of adjoining surface patches from the at least three surface patches, while also targeting an overall minimum of modification of positions of the at least eight control vertices;
• and
• process the modified positions of the at least a subset of the at least eight control vertices within the control mesh of the complex modelled surface for output by a physical device.

A non-transitory computer-readable medium encoding instructions operable to cause data processing apparatus to perform operations comprising:

• obtaining a complex modelled surface comprising a control mesh of control vertices, which define multiple smooth surface patches of the complex modelled surface;
• receiving input specifying at least a portion of the complex modelled surface to be smoothed;
• identifying from the input at least three of the multiple smooth surface patches corresponding to the at least a portion of the complex modeled surface to be smoothed, wherein the at least three surface patches are defined by at least eight of the control vertices from the control mesh;
• smoothing the at least a portion of the complex modeled surface based on continuity, wherein the smoothing comprises
• determining a measure of continuity at an interface between each pair of adjoining surface patches from the at least three surface patches, and
• modifying positions of at least a subset of the at least eight control vertices, thereby modifying the at least three surface patches, by targeting an overall improvement in the measures of continuity for the interfaces between the pairs of adjoining surface patches from the at least three surface patches, while also targeting an overall minimum of modification of positions of the at least eight control vertices;
• and
• processing the modified positions of the at least a subset of the at least eight control vertices within the control mesh of the complex modelled surface for output by a physical device.