Most of my experience with CG comes from the simulation modeling aspect (think more GEANT instead of CAD).

I'm not sure, I think Solvespace is history based, but I don't know enough about CAD geometry engines to give an in-depth answer. There are some architectural CAD papers on these.Įdit: maybe that's what Solvespace does - limit to just NURB surfaces? Way to go! The Dupin cyclide approach would have to approximate NURBS with cyclide sheets, but the intersection algorithms could be easier to implement because they are implicit quartic surfaces. One though I had was to just use Dupin cyclides (which covers the quadrics) and approximate everything else with cyclide sheets. Every time you add a new surface or curve type, then case analysis for the intersection algorithms goes up with the square, so the key is to limit severely the number of surface types. SpaceClaim has things the right way round to built a reliable CAD system: direct modeling X still v good b-rep kernel (ACIS).įree/open source doesn't have a good curved surface kernel.

OpenCASCADE in contrast only has to replay FreeCAD models, and there are modulo zero of those, and actually zero paying customers.

That's an extremely hostile evolutionary environment, and to survive Parasolid had to get extremely good. The reason is that all of sudden Parasolid has to be able to correctly rebuild every model ever made in Unigraphics, SolidEdge and SOLIDWORKS - including bug-for-bug compatibility. The best kernel, Parasolid, only started to get good when mainstream Unigraphics went history based parametric in 1992. Is Solvespace history based parametric CAD?įreeCAD's architecture that combines history based modeling with inferior kernel (Open CASCADE) is about the worst choice from a reliability standpoint.

Freecad architecture