WillAdams wrote:- exports to STL so needs a resolution option
No it doesn't, and/or the setting exists.
OpenSCAD exports an exact STL representation of its model. No approximations are made during export. However, the internal model is created as an approximation of what's described in the source code. When you say "cylinder", for instance, OpenSCAD actually creates a prism. You can control how many faces the prism has with the $fa, $fs and $fn
variables and arguments. In many 3D prints, you can see the default $fa=12 having generated a 30-sided prism, which I find annoying.
Because OpenSCAD works only with polyhedra internally (or polygons, when using it for 2D stuff), it does not need
to approximate anything when exporting STL. This is also why its DXF export is rubbish, with everything made out of segments (well, technically, the export is perfect, it's the internal model that's not appropriate for creating DXFs).