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Iterate Outer faces

Robert W.'s picture


is it possible to iterate only TopoDS_Face objects that are "visible" from outside?

qa qa's picture

Hello Robert,

No it is not possible. Moreover, the list of "visible" faces depends on camera position. If you want to calculate complete set of "visible" faces it is necessary to develop special algorithm from scratch.

qa qa

Robert W.'s picture

Hi and thanks for the answer,

I know that the visible faces depend on the camera position. I formulated my question wrong, because i thought that the title of my post was enough (and therefore i have written "visible" not visible).

I just want to have a list of the most outter faces in a 3D model, which means the faces that would be visible from the outside of the 3d model to the user, from any camera position (if i may formulate it so).

I was thinking of some kind of algorithm similar to backface culling, which would tell me which sides of my 3d model are visible to the user from the outside.

Are there any algorithms in opencascade or in 3D world that any of you know of that fulfill these requirements?

qa qa's picture


There is no such built-in algorithm.

Similar algorithm is included in commercial offer:

qa qa