I can import external STL to OpenScad, and use it as is. Yet I fail to manipulate the imported object, mostly with the difference() command. Mostly I need to cut pieces out of the imported STL. I know it can be done on the slicer (I was PrusaSlicer), yet I prefer to do it on the OpenScad because I can do it systematically on the source code. Also, sometimes the needs to cut are not as simple as the slicer can do.
For example: difference() { import("ext_stl.stl", convexity=20); cube([10,30,10]); }
I assume the imported STL is written in a format that OpenScad can't handle, so I wonder if there is any way to translate this input STL file into something that OpenScad could handle it?
I tried importing the STL into a module and use the reference to this module. I also tried loading it into PrusaSlicer and exporting as a new STL - also failed.