Automated trimming of a surface mesh

A method of trimming an open surface mesh, which comprises an inner mesh region delineated by an outer boundary, said method comprising:

• receiving an open surface mesh;
• determining a region of said open surface mesh to be maintained after trimming wherein said determining comprises:
• computing function values for a plurality of positions on said open surface by solving a diffusion function describing the evolution in time of the spatial distribution of a quantity over said surface mesh, said diffusion function being characterized by an equation of the type
• ∂
• f
• ⁡
• (
• ν
• ,
• t
• )
• ∂
• t
• =
• ∇
• ·
• A
• ⁢
• ∇
• f
• ⁡
• (
• v
• ,
• t
• )
• and applying boundary conditions specifying the function values of a solution of said equation along said outer boundary, wherein v is a spatial position, t is time, ∇⋅ is a divergence operator, A is a positive definite matrix, ∇ is a gradient operator and ƒ is a function defined on said open surface mesh, and
• identifying an open surface mesh region to be maintained after trimming wherein said region groups mesh positions with function values within a selected range;
• and
• trimming said open surface mesh by removing the open surface mesh regions outside the region identified to be maintained after trimming.

A system of trimming an open surface mesh, which comprises an inner mesh region delineated by an outer boundary, said system comprising a processing unit configured to perform the method comprising:

• receiving an open surface mesh;
• determining a cut-off line for trimming said open surface mesh wherein said determining comprises:
• computing function values for a plurality of positions on said open surface by solving a diffusion function describing the evolution in time of the spatial distribution of a quantity over said surface mesh, said diffusion function being characterized by an equation of the type
• ∂
• f
• ⁡
• (
• ν
• ,
• t
• )
• ∂
• t
• =
• ∇
• ·
• A
• ⁢
• ∇
• f
• ⁡
• (
• v
• ,
• t
• )
• and applying boundary conditions specifying the function values of a solution of said equation along said outer boundary, wherein v is a spatial position, t is time, ∇⋅ is a divergence operator, A is a positive definite matrix, ∇ is a gradient operator and ƒ is a function defined on said open surface mesh;
• calculating one or more isolines from said function values, such isoline joining surface mesh positions with the same function value,
• selecting from said one or more isolines an isoline enclosing a region of interest of said open surface mesh;
• and
• using the selected isoline as a cut-off line enclosing the surface mesh region to be maintained after trimming or using the selected isoline as a reference in post-processing for defining a cut-off line wherein the trajectory of said cut-off line is situated between said selected isoline and the outer boundary of said mesh;
• and
• trimming said open surface mesh by removing the surface mesh regions between said cut-off line and the outer boundary of said open surface mesh.