71–76 of 76 posts
How does FreeCAD compare to SketchUP? Does anyone know of a FOSS 2D drawing tool? I do a lot of pipe drawings (P&ID) and Visio is not ideal and AutoCAD is prohibitively expensive.
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Also note that there are nascent "F-Rep" kernels that may end-up replacing / supplementing the B-Rep kernels now used in solid CAD systems. They allow you to represent lattices and gradient structures that are essentially impossible to do with B-Rep systems.
Do you have any examples of these? Lattices and gradient structures are cool, but the problem is it's difficult to actually make these structures. 3D printers can make these structures, but they only accept data in B-Rep. Not to mention the 3D printers that can make these structures have closed controllers and run with proprietary software. The AMF file format can actually represent these things[0], but no one uses A…
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STL? What's that?
I think it's the standard file format export for CAD stuff, like gerbers are for hardware.
For other use cases, like transferring model data between programs, then STEP files (.STP) are very common instead. A STEP file contains much more data about the model than the equivalent STL file, so can be much more useful.
STEP seems like a pretty huge set of specs though (possibly a bit scary to implement from the ground up):
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OpenCascade is pretty much the only open source CAD kernel. There is brlcad, but that can only do CSG. We tried parasolid, then we got forced into using ACIS. We didn't really end up with much of a complete product in the end as this was government funded research.
Wow, was this Darpa's iFab? I don't recognize you from your username but I wouldn't be surprised if we worked together in some indirect way. I had literally the same experiences and explored all those same kernels. ... We concluded that the issues with OpenCascade's Boolean operations were so baked into the code that they'd probably be better off with a total rewrite. From what we could tell digging in the code, they…
What version of Open CASCADE did you look into the Boolean operations? The experience I have is also that they are not very fast, but more in terms of minutes not hours. From what I know there are 'old' style and 'new' style Boolean operations in the recent (6.9 and 7.0 beta) versions of Open CASCADE and the experience I am talking about is the 'new' style Boolean operations.
How big were the typical shapes you used, in terms of number of vertices/edges/faces? And for these shapes what was the comparative speed in Parasolid or ACIS kernels?
The thing to keep in mind when using it is that not all parts are equally usable. For a stable workflow you have to stick with what works. When you start using less polished corners FreeCAD tends to crash. It takes a bit of testing to figure this out.
Keep up the good work.
It's true. It's amazing. I'm using it at work for years for simple modeling and assembly. But now I can't. Why you ask? They compiled it with buggy version of C++11 library ("boost" or something) and it doesn't work at all. Thank you developers! You ruined my experience with this great software.
Has a bug been filed? And you can still use the older version, presumably.