If you had a formal drafting class, you probably learned about making orthographic projections–engineering drawings with multiple views (for example, top, front, and right). Even if you didn’t take the class, you’ve probably seen drawings like this where you view a 3D object as a series of 2D views from different angles.
These days, you are more likely to create a 3D model of an object, especially if you are going to 3D print it. After all, the 3D printer software is going to expect a model. When [Nightshade] wanted a laptop stand for his workbench, he started trying to do a 3D model. His final product though, was made by creating two views in Inkscape. They aren’t exactly orthographic projections of the final product, but the idea is similar.
Inkscape is a vector graphics program and generally creates SVG files, although it can also save EPS files. [Nightshade] used pstoedit to convert the EPS output to DXF format. DXF files are still two dimensional, but OpenSCAD can extrude DXF files into 3D shapes.
Just having a 3D shape of one view isn’t sufficient, though. The OpenSCAD script rotates the objects to the correct orientation and intersects them to form the final object. This is different from the usual cases of using Inkscape to trace a scan or generate simple text.
Inkscape can export DXF directly, but it has a lot of limitations. There are plugins (like the Big Blue Saw plugin) that work better and would probably also work in this application if you don’t want to uses pstoedit.
This technique is far from general purpose (some objects require more than two views and the profiles aren’t really projections). Still, this is a useful technique to generate 3D objects simply if you can get your head around the two shapes involved.
We’ve seen Inkscape used with printers and cutters before to either generate 2D laser cut patterns or define useful outlines. In this case, though, the shapes actually blend (through the intersection command) to form the final 3D object. Of course, you don’t have to use Inkscape. Any CAD program that puts out DXF (for example, FreeCAD or LibreCAD) ought to work with this technique.
Thanks [miceuz] for the tip!