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blobfish01

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Great comment! I think the size and scope of BRep modeling kernels is lost on 99% CAD users. IMHO: I have reached the point where I think there should be a generation of library development before a CAD application is even considered. This is coming from a person who has spent 10 years on an open source cad application, so I am not naive. The modeling kernel, of course, is lacking but also 3d visualization needs some love. More options in that space, but still lacking.

I evolved from pencil and paper, to text files, to minder. I stick to text and it works good for me. It is simple, fast to use, search works good, basic organization is there. Files are local and xml, so data is easy to extract if needed, backups and distribution are just file copy operations. https://github.com/phase1geo/Minder

I think it easy to get trapped by formatting and publishing. IMHO: Notes are fast and not pretty. If/when I come to the situation where I want to share, then formats like markdown or latex etc are a better fit. When I have to start 'coding' my notes, it becomes a time burden and I end up skipping it. In complicated situations, I will go the other extreme and fire up inkscape.

BRL-CAD 3 years ago

I guess we have a disconnect. I am talking about modeling kernel geometric definitions and data structures. Whether NX has or doesn't have the boolean terms (union, intersect ...etc) doesn't change the fact that parasolid is BRep. Just because parasolid supports boolean operations, doesn't mean it is CSG.

IMHO: Any shape defined by a CSG modeling kernel can be defined in a BRep modeling kernel. The reverse is not true, short of some kind of 'hack'. BOT(bag of triangles)? Hybrid with mesh modeling?

Thank you. I definitely could use help on the other platforms(mac, windows). I spent a huge amount of time deploying on those, which makes it great to hear it is running for you.

Sure any PRs for bugs are great. If you want to take on something ambitious, I would like to talk about it first so we waste as little developer time as possible.

BRL-CAD 3 years ago

brl-cad is CSG modeler with some BRep support. Opencascade is a BRep modeler that supports boolean operations. The industry gave up on CSG and went BRep decades ago.

BRL-CAD 3 years ago

In what ways is freecad using opencascade incorrectly?

I have never used openscad, but from what I understand there would be 2 major differences. The first is the geometry engine. Openscad uses a mesh modeler, where cadseer uses boundary representation(opencascade). The second is the user interface. Openscad uses code/script to drive the model generation where cadseer uses user interaction to build a model generating dependency graph.

Cadseer is not better for stamping dies. That is just my background. I think cad is getting more into specialized industries now that the foundational stuff is more concrete. I don't think most people appreciate what it takes to develop a solid modeling kernel.

I am using opencascade and doing solid modeling vs mesh modeling. So cadseer is closer to something like freecad vs blender.

A list of advantages and disadvantages should be done by somebody without bias. I will give you an example: I have incorporated 'git' revision control. With every update, files are wrote to disk and a git commit is made. With this git setup, I decided to exclude the typical 'undo' command and have no temporary files. I consider this an advantage because you get revision control and very little, if at all, loss of work when a crash occurs and the code base is cleaner and eliminates a fruitful source of bugs. Others might consider this a disadvantage because there is no traditional undo command.

Yes this is my pet project and haven't done any type of promotion until now.

I actually worked on freecad for a while. People familiar with freecad will recognize some of the things I made for freecad that I used in cadseer. I think freecad is great, but I wanted the freedom to do my own things, for better or worse.