11 ms·

Antimony – A fresh look at CAD software

357 points by rytis 11y ago

krschultz 11y ago
> Antimony is a computer-aided design (CAD) tool from a parallel universe in which CAD software evolved from Lisp machines rather than drafting tables. Funny, I'd be way more interested in the software engineering tools that are inspired by drafting tables than the mechanical engineering tools inspired by text editors. If you spend some time with anyone proficient with the big CAD/CAE programs you will see how efficient they are. OpenSCAD and others are familiar to programmers so they are easier to learn, but if you learn CAD/CAE software they make text editors feel clumsy and slow. For an added bonus, use one of the input controllers specifically built for CAD/CAE, it opens a whole other world.
- rwallace 11y ago
  Drafting table style software engineering tools have been around for decades. It turns out that the only ones programmers actually want to use are the ones that deal with something that is actually visual/geometric, i.e. the layout of graphic user interfaces, so those are the ones that were kept; that's how Visual Studio got its name. Nowadays when you need to cater to web browsers and mobile devices with a large range of screen sizes, even those are largely eschewed because the layout has to be redone at run time anyway. But there are still some in use by people who work on fixed size form layouts.
eggy 11y ago
I like the interface, and being a Blender3D user, I like nodes. However, I am long AutoCad / Inventor user, and I don't see what's new. You could do CSG modeling in AutoCad with union, difference, and intersection, and in Inventor you have that and sketch-based parametric modeling; update the sketch, and the model changes. Go back in the history, and change a value, and the model changes. In AutoCad you could use AutoLisp and later VBA. So aside from the look of the interface, and nodes vs. a history hierarchy what distinguishes it from decades-old parametric modelers?
- hugs 11y ago
  Compared to AutoCad/Inventor, cost and licensing are two huge differences. Antimony is open source: https://github.com/mkeeter/antimony/blob/develop/README.md https://github.com/mkeeter/antimony/blob/develop/README.md
  - eggy 11y ago
    True, but I was addressing the 'novelty' observation made, not cost and licensing. I do like the look of it.I just think it has been available, and is not new. Even the tease of Lisp machine when it has python in the background, not Lisp. For free, the now-opensource Solvespace [1] is a cool parametric 3D-modeler with STL check export and you can view some kinematic movement by dragging a constrained link in a linkage. [1] www.solvespace.com
bhouston 11y ago
This is neat, but from a usability standpoint most mechanical engineers prefer to work with draft style sketches rather than a node-based interface. Thus it is neat and impressive, but I am not sure it is what the consumers in the CAD market desire.
- leni536 11y ago
  Well this is a CAD software from a parallel universe, you wouldn't know what those mechanical engineers from that universe prefer. I'm a physicist and I only used one CAD software occasionally. In the CAD software I used I had to clone primitive objects to use them in multiple operations. If I wanted to change one dimension I had to update all the clones. Simply the acyclic graph model works better for this than the tree model. (Also some operations were irreversible, that was absolutely inexcusable.)
  - castell 11y ago
    In 3D CAD it's usually a parametric geometric modeling kernel. Everything is reversible and changeable, it usually it depends on an tree/directed graph.
- deleted 11y ago
  [deleted]
leni536 11y ago
OK, this is incredibly nice.
Vorcin83 11y ago
To add a bit of historical perspective, AutoCad could be extended through Lisp (AutoLisp), back in the day. So I posit that this approach is nothing new and unlikely to be what the customers of CAD packages don't already have.
- castell 11y ago
  ...and later also VBA (Visual Basic for Applications). The same goes for CATIA v5 (VBA).
  - ZenoArrow 11y ago
    AutoCAD also allows for .NET and C++ extensions now IIRC. I have a vague memory of JavaScript support coming soon too, perhaps it's already available.
- brudgers 11y ago
  AutoCad can still be extended using AutoLisp. However, AutoLisp is one of several scripting API's rather than a "first class value" in the drawing database. AutoLisp also lacks a macro facility.
alkonaut 11y ago
Looks nice. I have been working ten years professionally developing a CAD program, and if I could time travel and give my ten years younger self a single tip it would be to use a proper geometrical kernel (like CGAL) rather than doing anything with floating point. The tree rep is very cool. It could probably render implicitly using distance fields without even needing triangulation. http://iquilezles.org/www/articles/distfunctions/distfunctions.htm http://iquilezles.org/www/articles/distfunctions/distfunctio...
- mkeeter 11y ago
  Yes -- the images being drawn in the "3D" viewport are actually 2D bitmaps rendered directly from the f-rep then blitted to the screen (with a pixel shader that does proper depth culling on a per-pixel basis).
- mpweiher 11y ago
  > proper geometrical kernel (like CGAL) Wow, that looks amazing. Thanks for the pointer! http://www.cgal.org/ http://www.cgal.org/ (Pretending to add value, it's eminently googleable)
  - Osmium 11y ago
    Does anyone know a CGAL-like library with an iOS App Store-compatible open source license?
    - e12e 11y ago
      From the web-site it looks like it is available as a dual-license, GPL3+ and commercial?
      - Osmium 11y ago
        Thanks, I didn't realise that. Unfortunately, I wasn't looking to charge for my app, so a commercial license isn't feasible for me. As far as I know, GPL3+ is incompatible with the iOS App Store, so that's out too.
panic 11y ago
It's awesome how the nodes update as you drag things around in the viewer. I wonder whether there's a way to visually specify constraints (two points are coincident, two edges abut one another, and so on) instead of representing constraints implicitly through connections in the node graph.
Osmium 11y ago
This is really nice. Seems super easy to use, unlike other CAD/3D modelling software I've tried before. I think a lot of software could benefit from this 'timeless' graph/node based approach, rather than most UI's which only let you see the latest version with a long undo chain. It reminded me a bit of Bret Victor's drawing tool[1] too. Only problem, to me, is that it seems like a lot of work to get a UI like this off the ground. It'd be lovely to see support of a node-based UI built into some common UI frameworks. [1] http://worrydream.com/DrawingDynamicVisualizationsTalkAddendum/ http://worrydream.com/DrawingDynamicVisualizationsTalkAddend...
- galfarragem 11y ago
  >>seems super easy to use Did you try sketchup?
fit2rule 11y ago
Well, I thought OpenSCAD was a pretty fresh look at things: http://openscad.org/ http://openscad.org/ .. with fairly similar goals - only not for architecture, but rather 3d-printig ..
- niklasni1 11y ago
  OpenSCAD is functional (mostly), but it could have been great if they hadn't invented their own language. Then you could have had fancy features like error messages.
  - foldr 11y ago
    Openjscad (openjscad.org) is quite nice. I doubt it would be suitable for anything big, but it works well enough for small models.
castell 11y ago
First off, great work! Looks promising. Does it use a geometric modeling kernel? e.g open source Open CASCADE (http://en.wikipedia.org/wiki/Open_Cascade_Technology http://en.wikipedia.org/wiki/Open_Cascade_Technology ) ? Two other open source CAD come to my mind that use Python as primary scritping language: FreeCAD and the unmaintained HeeksCAD: http://en.wikipedia.org/wiki/FreeCAD http://en.wikipedia.org/wiki/FreeCAD , http://en.wikipedia.org/wiki/HeeksCAD http://en.wikipedia.org/wiki/HeeksCAD
- mkeeter 11y ago
  It uses a homebrew kernel based on functional representations (http://en.wikipedia.org/wiki/Function_representation http://en.wikipedia.org/wiki/Function_representation). Any function that comes out the end of the graph is rendered (as a bitmap) and blitted to the screen.
aswanson 11y ago
Impressive. Wonder how long it took to develop.
- mkeeter 11y ago
  I've been working on tools of this nature for about four years, though the only thing that's made it through mostly-unchanged is the geometry kernel. This grew out of my thesis work (2011-2013); in rough chronological order, here are a few documents from that time period: http://fab.cba.mit.edu/classes/S62.12/people/keeter.matt/index.html http://fab.cba.mit.edu/classes/S62.12/people/keeter.matt/ind... http://www.mattkeeter.com/projects/kokopelli/ http://www.mattkeeter.com/projects/kokopelli/ http://www.mattkeeter.com/research/thesis.pdf http://www.mattkeeter.com/research/thesis.pdf http://www.mattkeeter.com/research/siggraph_poster.pdf http://www.mattkeeter.com/research/siggraph_poster.pdf
  - phkahler 11y ago
    I just ran across your thesis a couple days ago while searching on representations for CSG. While I did not read it in detail, the representation seemed strange to me. I couldn't see how it can represent things like perfectly round holes. BTW I was ray tracing CSG objects for RT chess back in 2001. Here's a pic:http://www.caiman.us/scripts/fw/f282.html http://www.caiman.us/scripts/fw/f282.html I implemented a primitive called quadratic lathe which took 3 points on a curve and revolved them around the vertical axis as an implicit surface intersected with a slab to limit the vertical span. Most of the chess pieces were created by sketching them on graph paper and putting the profile coordinates into code. If you want to run it, beware of potential malware from sites that have it. Also, replace the SDL dll in there - somehow a bad version got in our original zip. I may not have source for the game any more, but the renderer has progressed a bit and now supports multithreading.
IshKebab 11y ago
Having used OpenSCAD, Solidworks and NX fairly extensively, I can say that "code-based" solid modelling systems are good for some specific things - anything that is highly parametric, for example: * Gears and sprockets * Fasteners (nuts & bolts) * Electrical components (ICs, etc) For anything else they aren't at all suitable. It's just a million times easier to be able to click on dimensions on the actual sketch and change them. You're never going to see a power tool or a tractor or whatever designed in OpenSCAD. Few 2D drawing programs are specified in code - the only ones I can think of are things like TikZ for Latex, and ... well there's a reason only Latex geeks use them. They aren't very easy to use. The main reason they exist is that it is much (like 100 times) easier to write a code-drive CAD system than a GUI-driven one.
- tiles 11y ago
  The ideal would be both worlds. 3D editor until you want to go in and change specific relations, which would be specified in code. Like editing an SVG or hand-editing its source, it's useful to have the option depending on your toolset.
  - shasta 11y ago
    The issue isn't whether you're editing text or visually interacting. It's that there's a tension between abstraction (parameterized models) and WYSIWYG editing.
  - stefanix 11y ago
    FreeCAD is a bit like this. See: http://freecadweb.org/wiki/index.php?title=Scripted_objects http://freecadweb.org/wiki/index.php?title=Scripted_objects
- niklasni1 11y ago
  I really like the idea of OpenSCAD, but the language is just unacceptably crappy. It's still better for me with my habits than anything graphical, though. If it had better capabilities for abstraction I think it'd much more suitable for large, complicated objects than a graphical editor.
rawe 11y ago
reminds me of Farbrausch Werkkzeug demoscene tool ( http://llg.cubic.org/docs/farbrauschDemos/ http://llg.cubic.org/docs/farbrauschDemos/ )
- frik 11y ago
  more info and kkrieger demo (just 96kb small ego shooter game): https://web.archive.org/web/20070304204422/http://www.theprodukkt.com/kkrieger https://web.archive.org/web/20070304204422/http://www.thepro...
colomon 11y ago
Okay, I'm a CAD software developer instead of an actual CAD engineer, so my perspective may be a bit biased. But this CSG (constructive solid geometry) idea is not in any way new. The reason it's kind of obscure now is that spline-based boundary representation systems (B-reps) took over the market decades ago. If you think about, say, the latest car designs, those free-flowing shapes are pretty easy to do in B-rep, and quite hard in CSG. [1] I've worked in CAD translators for the last two decades. Though both the IGES and STEP file formats include CSG modeling features, I have never implemented them. To the best of my recollection, I've never even had a request from a customer to do so. A pity, I think they'd be fun to try to implement... and most of the thorny bugs would officially be the B-rep geometry kernel's, not mine. :) [1] http://en.wikipedia.org/wiki/Boundary_representation http://en.wikipedia.org/wiki/Boundary_representation
- brudgers 11y ago
  From a marketing standpoint where everyone dreams of out Frank Ghery'ing Frank Ghery splines rule, but CSG is probably well suited from a practical standpoint for representing the walls and windows of the architecture that typically gets built. The problem of course, is that once there's a column with acanthus leaves, splines are the way to model its details and a WYSIWG needs them. For architecture, splines are in the aesthetic details, but constructive solids are a good tool for representing the important part of the constructed solids that are buildings.
- smoyer 11y ago
  And Auto-CAD had a Lisp engine in the '80s ... You could automate almost any function of the drawing system, build "macros" as well as patterns and even alter the DXF generation.
  - brudgers 11y ago
    AutoCad got AutoLisp as an update to R6 in January 1986. AutoCad got solid modelling in R11 with the "Advanced Modelling Extension" add-on in 1990. The whole history of AutoCad's feature evolution is that of a successful startup. There's an overview on AutoDesk's website: http://autodesk.blogs.com/between_the_lines/autocad-release-history.html http://autodesk.blogs.com/between_the_lines/autocad-release-...
jordigh 11y ago
Huh, homebrew non-free license. I wonder if the intention was even to make it non-free. It does not allow commercial use, which is forbidden by default. Oh well, at least homebrew licenses are getting rarer and rarer these days.
- cowsandmilk 11y ago
  > It does not allow commercial use, which is forbidden by default. what are you claiming here?
  - jordigh 11y ago
    The MIT license says, "Permission is hereby granted, [snip] including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software" The right to sell the software is part of the open source and free software definitions. A license needs to specify this, because by default copyright law does not grant this right. This homebrew license does not allow selling the software, thus it fails to be open source. Failing to meet this part of the definition is why MAME wasn't open source either until last week.
    - cowsandmilk 11y ago
      What part of their home-brew license does not allow commercial use? MAME was not free because they explicitly said "Redistributions may not be sold, nor may they be used in a commercial product or activity."
      - jordigh 11y ago
        Anything not explicitly allowed is forbidden. That's how copyright law works. "All rights reserved" is the default. You don't even have to claim it. All rights are reserved unless you relinquish them.
        dragonwriter 11y ago
keehun 11y ago
This looks like its direct ancestor by the same author a couple years earlier! Great work. http://www.mattkeeter.com/projects/kokopelli/ http://www.mattkeeter.com/projects/kokopelli/
Xophmeister 11y ago
So it's like POV-Ray[1], with a visual coding paradigm rather than purely text-based source, optimised for CAD rather than raytracing? [1] http://povray.org/ http://povray.org/
- elliotf 11y ago
  openscad (http://www.openscad.org http://www.openscad.org) which is mentioned elsewhere in this thread is a much more direct descendant of POV-ray.
blt 11y ago
The implicit surface representation is obviously great for 3D printing. I wonder if it would be suitable as input to a CAM system. (note: this is not a rhetorical question. I have no idea how CAM systems work.)
crimsonalucard 11y ago
What's the best free cad modelling tool for osx?
- Osmium 11y ago
  AutoCAD has an free education version: http://www.autodesk.com/education/free-software/all http://www.autodesk.com/education/free-software/all Very easy to obtain, but it can't be used for commercial applications obviously. There's also OpenSCAD (GPL): http://www.openscad.org http://www.openscad.org
- mryingster 11y ago
  I haven't found a free, native Mac CAD software that I like as much as Autodesk Inventor for Windows yet, but there are a number of free one available for the Mac. 123Design comes to mind [1] You can also peruse the comparison of CAD software at Wikipedia. [2] 1. http://www.123dapp.com/design http://www.123dapp.com/design 2. http://en.wikipedia.org/wiki/Comparison_of_computer-aided_design_editors http://en.wikipedia.org/wiki/Comparison_of_computer-aided_de...
- phkahler 11y ago
  >> What's the best free cad modelling tool for osx? I've been using SolveSpace: http://solvespace.com/index.pl http://solvespace.com/index.pl There is a Mac port but it's still on a branch. You can find a link to it in the forum thread here: http://solvespace.com/forum.pl?action=viewthread&parent=586 http://solvespace.com/forum.pl?action=viewthread&parent=586 Like the windows version it is a single executable file, so just put it somewhere and run it. It's worth reading the reference from top to bottom. Fantastic little program.
platz 11y ago
The expression problem in CAD software
willyt 11y ago
This is very interesting, there is definitely a big opportunity for CAD software that does things differently. A lot of the supposedly 'BIM enabled' and 'parametric' CAD software in use in the construction industry suffers from over defined and inflexible representations of real world objects, which often fail in the edge cases. I don't think software should be defining what it thinks a wall or a slab is or how they connect to each other, I think they should be giving architects and engineers better tools for defining and categorising these things ourselves.
mc_hammer 11y ago
looks great instead of using a popup menu for your commands consider using a drop down list with autocomplete -- and fuzzy matching like sublimetext Ctrl+P.. to see a demo of this goto http://www.sublimetext.com/ http://www.sublimetext.com/ and see slide #4 at the top of the page
nraynaud 11y ago
ok, here a very specific question: can I chamfer or fillet a specific edge that is resulting from a CSG subtraction? Because 3D printing supposes a very robust 3D CAD.
- kragen 11y ago
  This is a really great question. I don’t know the answer yet. I struggle with this problem every day when I design things in OpenSCAD, because OpenSCAD doesn't give your parametric model access to the results of the modeling operations in any way (!!) I think that Antimony kind of suffers from the same problem, but because it's using distance fields rather than plain CSG, it does have a “blend” operation (https://github.com/mkeeter/antimony/blob/develop/py/fab/shapes.py#L382 https://github.com/mkeeter/antimony/blob/develop/py/fab/shap...) that attempts to fillet the union of two shapes. Now, Antimony has inversion (complement, more or less), and set A \ B is just A ∩ B', which by De Morgan's Laws is equivalent to (A' ∪ B)'. So what happens if you attempt to approximate a filleted A \ B with invert(blend(invert(A), B))? I don’t know. But damn, I’m sure tempted to try it! Of course, even if that works, that won’t fillet a specific edge resulting from the subtraction. It will fillet all of them. Invariably, that is what I want.
  - nraynaud 11y ago
    in mold making for example, being able to chamfer some edges and keeping other edges very crisp (along the seam) is important.
    - kragen 11y ago
      That makes a lot of sense. I wonder if you can hack this in with a little more CSG stuff: maybe union the blended version with some giant solid blob that covers the crisp seam edges, and then intersect the result with the fully-crisp version. That's a pretty indirect way to solve the problem, but I wonder if it might work?
Arelius 11y ago
It's neat, but really just looks like a pretty primitive version of Houdini to me: http://www.sidefx.com/ http://www.sidefx.com/ Perhaps the emphasis on CAD instead of computer graphics is the primary differentiating factor, but it's really too early to tell. Good luck.
- kragen 11y ago
  Houdini is proprietary, and even people whose idea of fun is getting fucked over by proprietary software might balk at the price tag.
deleted 11y ago
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Animats 11y ago
CSG driven by a hierarchy of operations is the standard approach in CAD today. SolidWorks and Autodesk Inventor both work that way. Here's an Inventor tutorial on modeling the wheel of a scooter.[1] I picked this tutorial because the part and the operations used are very similar to the the Antimony screwdriver example. Antimony looks like a nice entry-level program for this sort of thing. It's way ahead of mesh editors. Those are for graphics, not physical objects. In a mesh editor, you can't move a hole cleanly. In a mesh, the concept of "hole" has been lost. What you get with the big expensive programs is 1) a GUI that scales well when you need to design something complicated (people do jet engines in these programs), 2) a constraint solver, where you can specify constraints and let the system work out a solution, and 3) lots of additional engineering tools. It's nice to see the low end catching up. [1] https://www.youtube.com/watch?v=bLZzS1k4tLs https://www.youtube.com/watch?v=bLZzS1k4tLs
fzn 11y ago
This looks _very_ interesting (from a DIYer point of view), however building under GNU/Linux amd64 isn't seamless. (Missing --std statements in the Makefile, notably) I find openscad quite painful to use, I whish I learned about Antimony before. I think this has lot of potential, as a lightweigth, intuitive, free software, notably in the maker/diyer scene.
- kragen 11y ago
  What changes did you have to make to get it to build?
  - fzn 11y ago
    #define M_PI and M_2_PI in three headers add --std=c99 to CFLAGS and --std=c++11 to CXXFLAGS in Makefile Still doesn't build, see: http://pastebin.com/T17kCyG3 http://pastebin.com/T17kCyG3
    - kragen 11y ago
      Looks like a Qt version skew problem; http://doc.qt.io/qt-5/qjsonarray.html http://doc.qt.io/qt-5/qjsonarray.html suggests that in the current Qt, the QJsonArray constructors take either zero or one arguments, and the code is trying to invoke this one introduced in Qt 5.4 http://doc.qt.io/qt-5/qjsonarray.html#QJsonArray-2 http://doc.qt.io/qt-5/qjsonarray.html#QJsonArray-2, while your installation of Qt5 seems to only declare a two-argument constructor and the copy-constructor. You probably already knew that, but I think it means the cure is probably to install Qt 5.4 (or the prerelease 5.5) from source. Do you see other compile problems if you run make -k, or just that one?
      - fzn 11y ago
        After updating qt5base-dev using debian experimental, and adding -fPIC to the CXXFLAGS, it compiled nicely :) edit: there seems to be a slight problem with text rendering tho(only lowercase 'a' and bullet points are drawn), see http://imgur.com/MiX1hvL http://imgur.com/MiX1hvL More of a qt5 issue I think
galfarragem 11y ago
As an architect, I wonder how this software can be useful in the real world, what itch does it scratch?
grogenaut 11y ago
Tangentally related... if you are a student... Solid works is ~$180/year... and autodesk software is free for 3 years from your enrollment. Haven't tried autodesk's offerings but Solidworks is unbelievably powerful software. It's incredible. Guess what makes you a student? Any community college class. So go take a welding class.
poseid 11y ago
interesting concepts. some examples look like graphs.

357 points by rytis 11y ago

> Antimony is a computer-aided design (CAD) tool from a parallel universe in which CAD software evolved from Lisp machines rather than drafting tables. Funny, I'd be way more interested in the software engineering tools that are inspired by drafting tables than the mechanical engineering tools inspired by text editors. If you spend some time with anyone proficient with the big CAD/CAE programs you will see how efficient they are. OpenSCAD and others are familiar to programmers so they are easier to learn, but if you learn CAD/CAE software they make text editors feel clumsy and slow. For an added bonus, use one of the input controllers specifically built for CAD/CAE, it opens a whole other world.

rwallace 11y ago
Drafting table style software engineering tools have been around for decades. It turns out that the only ones programmers actually want to use are the ones that deal with something that is actually visual/geometric, i.e. the layout of graphic user interfaces, so those are the ones that were kept; that's how Visual Studio got its name. Nowadays when you need to cater to web browsers and mobile devices with a large range of screen sizes, even those are largely eschewed because the layout has to be redone at run time anyway. But there are still some in use by people who work on fixed size form layouts.

eggy 11y ago

I like the interface, and being a Blender3D user, I like nodes. However, I am long AutoCad / Inventor user, and I don't see what's new. You could do CSG modeling in AutoCad with union, difference, and intersection, and in Inventor you have that and sketch-based parametric modeling; update the sketch, and the model changes. Go back in the history, and change a value, and the model changes. In AutoCad you could use AutoLisp and later VBA. So aside from the look of the interface, and nodes vs. a history hierarchy what distinguishes it from decades-old parametric modelers?

hugs 11y ago
Compared to AutoCad/Inventor, cost and licensing are two huge differences. Antimony is open source: https://github.com/mkeeter/antimony/blob/develop/README.md https://github.com/mkeeter/antimony/blob/develop/README.md
- eggy 11y ago
  True, but I was addressing the 'novelty' observation made, not cost and licensing. I do like the look of it.I just think it has been available, and is not new. Even the tease of Lisp machine when it has python in the background, not Lisp. For free, the now-opensource Solvespace [1] is a cool parametric 3D-modeler with STL check export and you can view some kinematic movement by dragging a constrained link in a linkage. [1] www.solvespace.com

bhouston 11y ago

This is neat, but from a usability standpoint most mechanical engineers prefer to work with draft style sketches rather than a node-based interface. Thus it is neat and impressive, but I am not sure it is what the consumers in the CAD market desire.

leni536 11y ago
Well this is a CAD software from a parallel universe, you wouldn't know what those mechanical engineers from that universe prefer. I'm a physicist and I only used one CAD software occasionally. In the CAD software I used I had to clone primitive objects to use them in multiple operations. If I wanted to change one dimension I had to update all the clones. Simply the acyclic graph model works better for this than the tree model. (Also some operations were irreversible, that was absolutely inexcusable.)
- castell 11y ago
  In 3D CAD it's usually a parametric geometric modeling kernel. Everything is reversible and changeable, it usually it depends on an tree/directed graph.
deleted 11y ago
[deleted]

leni536 11y ago

OK, this is incredibly nice.

Vorcin83 11y ago

To add a bit of historical perspective, AutoCad could be extended through Lisp (AutoLisp), back in the day. So I posit that this approach is nothing new and unlikely to be what the customers of CAD packages don't already have.

castell 11y ago
...and later also VBA (Visual Basic for Applications). The same goes for CATIA v5 (VBA).
- ZenoArrow 11y ago
  AutoCAD also allows for .NET and C++ extensions now IIRC. I have a vague memory of JavaScript support coming soon too, perhaps it's already available.
brudgers 11y ago
AutoCad can still be extended using AutoLisp. However, AutoLisp is one of several scripting API's rather than a "first class value" in the drawing database. AutoLisp also lacks a macro facility.

alkonaut 11y ago

Looks nice. I have been working ten years professionally developing a CAD program, and if I could time travel and give my ten years younger self a single tip it would be to use a proper geometrical kernel (like CGAL) rather than doing anything with floating point. The tree rep is very cool. It could probably render implicitly using distance fields without even needing triangulation. http://iquilezles.org/www/articles/distfunctions/distfunctions.htm http://iquilezles.org/www/articles/distfunctions/distfunctio...

mkeeter 11y ago
Yes -- the images being drawn in the "3D" viewport are actually 2D bitmaps rendered directly from the f-rep then blitted to the screen (with a pixel shader that does proper depth culling on a per-pixel basis).
mpweiher 11y ago
> proper geometrical kernel (like CGAL) Wow, that looks amazing. Thanks for the pointer! http://www.cgal.org/ http://www.cgal.org/ (Pretending to add value, it's eminently googleable)
- Osmium 11y ago
  Does anyone know a CGAL-like library with an iOS App Store-compatible open source license?
  - e12e 11y ago
    From the web-site it looks like it is available as a dual-license, GPL3+ and commercial?
    - Osmium 11y ago
      Thanks, I didn't realise that. Unfortunately, I wasn't looking to charge for my app, so a commercial license isn't feasible for me. As far as I know, GPL3+ is incompatible with the iOS App Store, so that's out too.

panic 11y ago

It's awesome how the nodes update as you drag things around in the viewer. I wonder whether there's a way to visually specify constraints (two points are coincident, two edges abut one another, and so on) instead of representing constraints implicitly through connections in the node graph.

Osmium 11y ago

This is really nice. Seems super easy to use, unlike other CAD/3D modelling software I've tried before. I think a lot of software could benefit from this 'timeless' graph/node based approach, rather than most UI's which only let you see the latest version with a long undo chain. It reminded me a bit of Bret Victor's drawing tool[1] too. Only problem, to me, is that it seems like a lot of work to get a UI like this off the ground. It'd be lovely to see support of a node-based UI built into some common UI frameworks. [1] http://worrydream.com/DrawingDynamicVisualizationsTalkAddendum/ http://worrydream.com/DrawingDynamicVisualizationsTalkAddend...

galfarragem 11y ago
>>seems super easy to use Did you try sketchup?

fit2rule 11y ago

Well, I thought OpenSCAD was a pretty fresh look at things: http://openscad.org/ http://openscad.org/ .. with fairly similar goals - only not for architecture, but rather 3d-printig ..

niklasni1 11y ago
OpenSCAD is functional (mostly), but it could have been great if they hadn't invented their own language. Then you could have had fancy features like error messages.
- foldr 11y ago
  Openjscad (openjscad.org) is quite nice. I doubt it would be suitable for anything big, but it works well enough for small models.

castell 11y ago

First off, great work! Looks promising. Does it use a geometric modeling kernel? e.g open source Open CASCADE (http://en.wikipedia.org/wiki/Open_Cascade_Technology http://en.wikipedia.org/wiki/Open_Cascade_Technology ) ? Two other open source CAD come to my mind that use Python as primary scritping language: FreeCAD and the unmaintained HeeksCAD: http://en.wikipedia.org/wiki/FreeCAD http://en.wikipedia.org/wiki/FreeCAD , http://en.wikipedia.org/wiki/HeeksCAD http://en.wikipedia.org/wiki/HeeksCAD

mkeeter 11y ago
It uses a homebrew kernel based on functional representations (http://en.wikipedia.org/wiki/Function_representation http://en.wikipedia.org/wiki/Function_representation). Any function that comes out the end of the graph is rendered (as a bitmap) and blitted to the screen.

aswanson 11y ago

Impressive. Wonder how long it took to develop.

mkeeter 11y ago
I've been working on tools of this nature for about four years, though the only thing that's made it through mostly-unchanged is the geometry kernel. This grew out of my thesis work (2011-2013); in rough chronological order, here are a few documents from that time period: http://fab.cba.mit.edu/classes/S62.12/people/keeter.matt/index.html http://fab.cba.mit.edu/classes/S62.12/people/keeter.matt/ind... http://www.mattkeeter.com/projects/kokopelli/ http://www.mattkeeter.com/projects/kokopelli/ http://www.mattkeeter.com/research/thesis.pdf http://www.mattkeeter.com/research/thesis.pdf http://www.mattkeeter.com/research/siggraph_poster.pdf http://www.mattkeeter.com/research/siggraph_poster.pdf
- phkahler 11y ago
  I just ran across your thesis a couple days ago while searching on representations for CSG. While I did not read it in detail, the representation seemed strange to me. I couldn't see how it can represent things like perfectly round holes. BTW I was ray tracing CSG objects for RT chess back in 2001. Here's a pic:http://www.caiman.us/scripts/fw/f282.html http://www.caiman.us/scripts/fw/f282.html I implemented a primitive called quadratic lathe which took 3 points on a curve and revolved them around the vertical axis as an implicit surface intersected with a slab to limit the vertical span. Most of the chess pieces were created by sketching them on graph paper and putting the profile coordinates into code. If you want to run it, beware of potential malware from sites that have it. Also, replace the SDL dll in there - somehow a bad version got in our original zip. I may not have source for the game any more, but the renderer has progressed a bit and now supports multithreading.

IshKebab 11y ago

Having used OpenSCAD, Solidworks and NX fairly extensively, I can say that "code-based" solid modelling systems are good for some specific things - anything that is highly parametric, for example: * Gears and sprockets * Fasteners (nuts & bolts) * Electrical components (ICs, etc) For anything else they aren't at all suitable. It's just a million times easier to be able to click on dimensions on the actual sketch and change them. You're never going to see a power tool or a tractor or whatever designed in OpenSCAD. Few 2D drawing programs are specified in code - the only ones I can think of are things like TikZ for Latex, and ... well there's a reason only Latex geeks use them. They aren't very easy to use. The main reason they exist is that it is much (like 100 times) easier to write a code-drive CAD system than a GUI-driven one.

tiles 11y ago
The ideal would be both worlds. 3D editor until you want to go in and change specific relations, which would be specified in code. Like editing an SVG or hand-editing its source, it's useful to have the option depending on your toolset.
- shasta 11y ago
  The issue isn't whether you're editing text or visually interacting. It's that there's a tension between abstraction (parameterized models) and WYSIWYG editing.
- stefanix 11y ago
  FreeCAD is a bit like this. See: http://freecadweb.org/wiki/index.php?title=Scripted_objects http://freecadweb.org/wiki/index.php?title=Scripted_objects
niklasni1 11y ago
I really like the idea of OpenSCAD, but the language is just unacceptably crappy. It's still better for me with my habits than anything graphical, though. If it had better capabilities for abstraction I think it'd much more suitable for large, complicated objects than a graphical editor.

rawe 11y ago

reminds me of Farbrausch Werkkzeug demoscene tool ( http://llg.cubic.org/docs/farbrauschDemos/ http://llg.cubic.org/docs/farbrauschDemos/ )

frik 11y ago
more info and kkrieger demo (just 96kb small ego shooter game): https://web.archive.org/web/20070304204422/http://www.theprodukkt.com/kkrieger https://web.archive.org/web/20070304204422/http://www.thepro...

colomon 11y ago

Okay, I'm a CAD software developer instead of an actual CAD engineer, so my perspective may be a bit biased. But this CSG (constructive solid geometry) idea is not in any way new. The reason it's kind of obscure now is that spline-based boundary representation systems (B-reps) took over the market decades ago. If you think about, say, the latest car designs, those free-flowing shapes are pretty easy to do in B-rep, and quite hard in CSG. [1] I've worked in CAD translators for the last two decades. Though both the IGES and STEP file formats include CSG modeling features, I have never implemented them. To the best of my recollection, I've never even had a request from a customer to do so. A pity, I think they'd be fun to try to implement... and most of the thorny bugs would officially be the B-rep geometry kernel's, not mine. :) [1] http://en.wikipedia.org/wiki/Boundary_representation http://en.wikipedia.org/wiki/Boundary_representation

brudgers 11y ago
From a marketing standpoint where everyone dreams of out Frank Ghery'ing Frank Ghery splines rule, but CSG is probably well suited from a practical standpoint for representing the walls and windows of the architecture that typically gets built. The problem of course, is that once there's a column with acanthus leaves, splines are the way to model its details and a WYSIWG needs them. For architecture, splines are in the aesthetic details, but constructive solids are a good tool for representing the important part of the constructed solids that are buildings.
smoyer 11y ago
And Auto-CAD had a Lisp engine in the '80s ... You could automate almost any function of the drawing system, build "macros" as well as patterns and even alter the DXF generation.
- brudgers 11y ago
  AutoCad got AutoLisp as an update to R6 in January 1986. AutoCad got solid modelling in R11 with the "Advanced Modelling Extension" add-on in 1990. The whole history of AutoCad's feature evolution is that of a successful startup. There's an overview on AutoDesk's website: http://autodesk.blogs.com/between_the_lines/autocad-release-history.html http://autodesk.blogs.com/between_the_lines/autocad-release-...

jordigh 11y ago

Huh, homebrew non-free license. I wonder if the intention was even to make it non-free. It does not allow commercial use, which is forbidden by default. Oh well, at least homebrew licenses are getting rarer and rarer these days.

cowsandmilk 11y ago
> It does not allow commercial use, which is forbidden by default. what are you claiming here?
- jordigh 11y ago
  The MIT license says, "Permission is hereby granted, [snip] including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software" The right to sell the software is part of the open source and free software definitions. A license needs to specify this, because by default copyright law does not grant this right. This homebrew license does not allow selling the software, thus it fails to be open source. Failing to meet this part of the definition is why MAME wasn't open source either until last week.
  - cowsandmilk 11y ago
    What part of their home-brew license does not allow commercial use? MAME was not free because they explicitly said "Redistributions may not be sold, nor may they be used in a commercial product or activity."
    - jordigh 11y ago
      Anything not explicitly allowed is forbidden. That's how copyright law works. "All rights reserved" is the default. You don't even have to claim it. All rights are reserved unless you relinquish them.
      - dragonwriter 11y ago

keehun 11y ago

This looks like its direct ancestor by the same author a couple years earlier! Great work. http://www.mattkeeter.com/projects/kokopelli/ http://www.mattkeeter.com/projects/kokopelli/

Xophmeister 11y ago

So it's like POV-Ray[1], with a visual coding paradigm rather than purely text-based source, optimised for CAD rather than raytracing? [1] http://povray.org/ http://povray.org/

elliotf 11y ago
openscad (http://www.openscad.org http://www.openscad.org) which is mentioned elsewhere in this thread is a much more direct descendant of POV-ray.

blt 11y ago

The implicit surface representation is obviously great for 3D printing. I wonder if it would be suitable as input to a CAM system. (note: this is not a rhetorical question. I have no idea how CAM systems work.)

crimsonalucard 11y ago

What's the best free cad modelling tool for osx?

Osmium 11y ago
AutoCAD has an free education version: http://www.autodesk.com/education/free-software/all http://www.autodesk.com/education/free-software/all Very easy to obtain, but it can't be used for commercial applications obviously. There's also OpenSCAD (GPL): http://www.openscad.org http://www.openscad.org
mryingster 11y ago
I haven't found a free, native Mac CAD software that I like as much as Autodesk Inventor for Windows yet, but there are a number of free one available for the Mac. 123Design comes to mind [1] You can also peruse the comparison of CAD software at Wikipedia. [2] 1. http://www.123dapp.com/design http://www.123dapp.com/design 2. http://en.wikipedia.org/wiki/Comparison_of_computer-aided_design_editors http://en.wikipedia.org/wiki/Comparison_of_computer-aided_de...
phkahler 11y ago
>> What's the best free cad modelling tool for osx? I've been using SolveSpace: http://solvespace.com/index.pl http://solvespace.com/index.pl There is a Mac port but it's still on a branch. You can find a link to it in the forum thread here: http://solvespace.com/forum.pl?action=viewthread&parent=586 http://solvespace.com/forum.pl?action=viewthread&parent=586 Like the windows version it is a single executable file, so just put it somewhere and run it. It's worth reading the reference from top to bottom. Fantastic little program.

platz 11y ago

The expression problem in CAD software

willyt 11y ago

This is very interesting, there is definitely a big opportunity for CAD software that does things differently. A lot of the supposedly 'BIM enabled' and 'parametric' CAD software in use in the construction industry suffers from over defined and inflexible representations of real world objects, which often fail in the edge cases. I don't think software should be defining what it thinks a wall or a slab is or how they connect to each other, I think they should be giving architects and engineers better tools for defining and categorising these things ourselves.

mc_hammer 11y ago

looks great instead of using a popup menu for your commands consider using a drop down list with autocomplete -- and fuzzy matching like sublimetext Ctrl+P.. to see a demo of this goto http://www.sublimetext.com/ http://www.sublimetext.com/ and see slide #4 at the top of the page

nraynaud 11y ago

ok, here a very specific question: can I chamfer or fillet a specific edge that is resulting from a CSG subtraction? Because 3D printing supposes a very robust 3D CAD.

kragen 11y ago
This is a really great question. I don’t know the answer yet. I struggle with this problem every day when I design things in OpenSCAD, because OpenSCAD doesn't give your parametric model access to the results of the modeling operations in any way (!!) I think that Antimony kind of suffers from the same problem, but because it's using distance fields rather than plain CSG, it does have a “blend” operation (https://github.com/mkeeter/antimony/blob/develop/py/fab/shapes.py#L382 https://github.com/mkeeter/antimony/blob/develop/py/fab/shap...) that attempts to fillet the union of two shapes. Now, Antimony has inversion (complement, more or less), and set A \ B is just A ∩ B', which by De Morgan's Laws is equivalent to (A' ∪ B)'. So what happens if you attempt to approximate a filleted A \ B with invert(blend(invert(A), B))? I don’t know. But damn, I’m sure tempted to try it! Of course, even if that works, that won’t fillet a specific edge resulting from the subtraction. It will fillet all of them. Invariably, that is what I want.
- nraynaud 11y ago
  in mold making for example, being able to chamfer some edges and keeping other edges very crisp (along the seam) is important.
  - kragen 11y ago
    That makes a lot of sense. I wonder if you can hack this in with a little more CSG stuff: maybe union the blended version with some giant solid blob that covers the crisp seam edges, and then intersect the result with the fully-crisp version. That's a pretty indirect way to solve the problem, but I wonder if it might work?

Arelius 11y ago

It's neat, but really just looks like a pretty primitive version of Houdini to me: http://www.sidefx.com/ http://www.sidefx.com/ Perhaps the emphasis on CAD instead of computer graphics is the primary differentiating factor, but it's really too early to tell. Good luck.

kragen 11y ago
Houdini is proprietary, and even people whose idea of fun is getting fucked over by proprietary software might balk at the price tag.

deleted 11y ago

[deleted]

Animats 11y ago

CSG driven by a hierarchy of operations is the standard approach in CAD today. SolidWorks and Autodesk Inventor both work that way. Here's an Inventor tutorial on modeling the wheel of a scooter.[1] I picked this tutorial because the part and the operations used are very similar to the the Antimony screwdriver example. Antimony looks like a nice entry-level program for this sort of thing. It's way ahead of mesh editors. Those are for graphics, not physical objects. In a mesh editor, you can't move a hole cleanly. In a mesh, the concept of "hole" has been lost. What you get with the big expensive programs is 1) a GUI that scales well when you need to design something complicated (people do jet engines in these programs), 2) a constraint solver, where you can specify constraints and let the system work out a solution, and 3) lots of additional engineering tools. It's nice to see the low end catching up. [1] https://www.youtube.com/watch?v=bLZzS1k4tLs https://www.youtube.com/watch?v=bLZzS1k4tLs

fzn 11y ago

This looks _very_ interesting (from a DIYer point of view), however building under GNU/Linux amd64 isn't seamless. (Missing --std statements in the Makefile, notably) I find openscad quite painful to use, I whish I learned about Antimony before. I think this has lot of potential, as a lightweigth, intuitive, free software, notably in the maker/diyer scene.

kragen 11y ago
What changes did you have to make to get it to build?
- fzn 11y ago
  #define M_PI and M_2_PI in three headers add --std=c99 to CFLAGS and --std=c++11 to CXXFLAGS in Makefile Still doesn't build, see: http://pastebin.com/T17kCyG3 http://pastebin.com/T17kCyG3
  - kragen 11y ago
    Looks like a Qt version skew problem; http://doc.qt.io/qt-5/qjsonarray.html http://doc.qt.io/qt-5/qjsonarray.html suggests that in the current Qt, the QJsonArray constructors take either zero or one arguments, and the code is trying to invoke this one introduced in Qt 5.4 http://doc.qt.io/qt-5/qjsonarray.html#QJsonArray-2 http://doc.qt.io/qt-5/qjsonarray.html#QJsonArray-2, while your installation of Qt5 seems to only declare a two-argument constructor and the copy-constructor. You probably already knew that, but I think it means the cure is probably to install Qt 5.4 (or the prerelease 5.5) from source. Do you see other compile problems if you run make -k, or just that one?
    - fzn 11y ago
      After updating qt5base-dev using debian experimental, and adding -fPIC to the CXXFLAGS, it compiled nicely :) edit: there seems to be a slight problem with text rendering tho(only lowercase 'a' and bullet points are drawn), see http://imgur.com/MiX1hvL http://imgur.com/MiX1hvL More of a qt5 issue I think

galfarragem 11y ago

As an architect, I wonder how this software can be useful in the real world, what itch does it scratch?

grogenaut 11y ago

Tangentally related... if you are a student... Solid works is ~$180/year... and autodesk software is free for 3 years from your enrollment. Haven't tried autodesk's offerings but Solidworks is unbelievably powerful software. It's incredible. Guess what makes you a student? Any community college class. So go take a welding class.

poseid 11y ago

interesting concepts. some examples look like graphs.