So, needed to export from OpenSCAD so we can cut some stuff on a laser cutter....
God this is a nightmare process, spent a good few hours trying to figure out what's up with it, and finally figured it out. The "proper" method is as follows:-
1) Export from OpenSCAD to a PNG file.
2) Load the PNG file into Inkscape.
3) Have Inkscape run a path trace algorithm on the png file.
4) Spend ages (even a simple file can be five-ten minutes of fiddling) cleaning up the paths.
5) Complain, moan be annoyed as Inkscape's output just isn't straight, and is strangely laid out.
Okay, number 5 is just my step mostly I finally decided that this just wasn't a good method of handling the export, so after a quick google search I discover that the program I used to slice the STL files I generate from OpenSCAD for printing on the RepRap will also export SVG files... and what it does is generate it so each layer is a grouped option in Inkscape... hmmm.... okay, so the new method (which by the way takes about thirty seconds for me now) is:-
1) Export from OpenSCAD to an STL file.
2) Load Slic3r and tell it to export the STL as an SVG file. (Note here, see below)
3) Load the resulting SVG into Inkscape.
4) Delete all layers not needed for the cut.
5) Ungroup the layer, set No Fill and have the Stroke solid with a 1 pixel width.
6) Rejoice as the output looks perfect.... then save the file.
Okay, the only concerns here is that Slic3r needs to have a few settings adjusted to generate nice looking SVG slices, first off, 0 Infill, 1 Perimeter and 0 Solid Layers, not sure if this really makes much difference but it works for me.
Given this I can now generate what appear to be valid SVG files for use with the Laser Cutter.... hope so as the Hubby is going to give them a whirl in a few hours.