6 ms·

Plasticity: CAD for Artists

103 points by dgellow 3y ago

skybrian 3y ago
I’m wondering whether this is useful for 3D printing and whether you can add important measurements when it matters (to make parts that fit.)
- CharlesW 3y ago
  From a 2022 discussion: https://news.ycombinator.com/item?id=30695360 https://news.ycombinator.com/item?id=30695360 > Are there parametric features? eg. Can I say "this line is 35mm long"? > I want to emphasize to everyone that this is for concept artists. It’s nurbs used to create interesting shapes and fillets. While there are some parametric features, they’re completely de emphasized compared to something like fusion or solidworks
  - oktwtf 3y ago
    The software has evolved significantly since 2022, I'd even say that the dev has been flexible and enabled functionality to bridge some more traditional CAD use cases in modern versions. For example when you sketch shapes on a workplane you are able to define the measurement aspects, diameters, offsets, lengths; you can even quickly define relative angles when drawing out segmented lines. However there are no parametric controls for the elements of your shapes or drawings. Keeping these constraints out of mind certainly helps me get into a flow when modeling, much more akin to subd or poly modeling while maintaining the benefits of NURBS. But for adapting models quickly for more flexible designs isn't /really/ the tool for it. You can take it pretty far though! I personally use Plasticity to model all kinds of things including 3d-printed items (vacuum wall mounting, iPhone lens mount, storage cases, clips...) All of these items needed to be measured accurately and Plastiticy was able to handle that without issue. I've been using 3d software for 20+ years, Max, Maya, Blender, XSI, Houdini, Wings3d, Lightwave, Modo, ZBrush, Mudbox... "lots" of 3d software. Some get the job done and some are even a pleasure to use, Plasticity decidedly in my mind does both.
- timothyb89 3y ago
  I've been using it for light CAD work to design stuff for (hobbyist) 3d printing. You can use exact measurements just fine. The main issue is that it isn't parametric but for my needs that isn't a big issue, and the one-time $150 pricetag is wildly easier to swallow than a Fusion 360 subscription. It's a lot like Blender, if Blender was a few degrees more usable for CAD. That said, I've yet to try the Blender CAD Sketcher addon (https://www.cadsketcher.com/ https://www.cadsketcher.com/).
  - declaredapple 3y ago
    Oh I need to try that addon. I've been meaning to look for a Fusion360 alternative that can run on linux and doesn't cost $$$$/yr.
    - graypegg 3y ago
      There's also FreeCAD, which is getting better! Definitely worth trying the RealThunder fork [0] that handles some geometry better than the upstream branch, and is kept up to date. It's still weird. That's for sure. But very much usable as a fusion360 replacement for simple to intermediate 3D printing work. [0] https://github.com/realthunder/FreeCAD/releases https://github.com/realthunder/FreeCAD/releases
      - rcarmo 3y ago
        I try every FreeCAD release in hopes the UX and tool naming improves, but so far no dice. It’s almost amazingly obscure by design.
        thrtythreeforty 3y ago
        I really want to like it. I am well accustomed to dealing with quirky FOSS UIs. But it is so bad. Something that takes one click in Solidworks or Solid Edge takes ten, and at any point if there is an error, there is no feedback. If it looked like FreeCAD was trying to improve the UI I think I'd be throwing some money their way to fund it. But it appears they're happy with the way it works, as these paper cuts have actually gotten worse over time. It's just FreeCAD, not FOSS-CAD-as-a-whole. Kicad gets better and easier to use each release and I am well aware what a gift it is to engineering work.
- bigboy12 3y ago
  It’s a really an amazing piece of software.
- onthecanposting 3y ago
  I use plasticity exclusively for 3D printing. I'm a huge fan. I also deeply appreciate a no-nonsense perpetual license for a fair price. You can't define persistent dimensional or relational constraints; however you can iterate and edit so fast that I have never missed it. Part tolerance is off? Grab a surface and pull it in or out to the length you need. If you need highly parametric parts, I might favor OpenSCAD or CadQuery (python), anyway.
itronitron 3y ago
this link is just an ad
- owenpalmer 3y ago
  why do you say that?
  - fddrdplktrew 3y ago
    I installed a binary but wont register to use it "for free"... I'm going to stick with Blender.
    - cs3f16 3y ago
      Same here
    - owenpalmer 3y ago
      Ah yeah that's a major turn off
  - itronitron 3y ago
    I say that because the linked page is just there to get people to download the product and doesn't provide any real information on anything interesting, even though the software itself may be of interest to many people here.
    - dgellow 3y ago
      It’s the landing page of the project…
alted 3y ago
Plasticity is interesting because it is maybe the only way to run the Parasolid geometry kernel natively on Linux right now. Parasolid, the library used to perform the geometric operations (the most difficult and important part of a CAD program) also powers the likes of SolidWorks (the industry standard), NX, and Onshape, and is arguably the best in the world. Its licensing cost is presumably a large part of the Plasticity price.
- fsloth 3y ago
  Meh. Geometry kernels are oversold. Triangulate, CSG and triumph. CSG is the non-trivial part - and Manifold (https://github.com/elalish/manifold https://github.com/elalish/manifold) is excellent at this. At least for consumer stuff where you anyway eventually just want triangles for either rendering or 3d printing. If your industrial workflow includes CNC machines you may benefit from actual analytic surface cuts and unions - maybe.
- Buttons840 3y ago
  Why is it difficult (geometric operations)? Do you have any suggestions on how to learn more about it?
  - skgough 3y ago
    There are two aspects of CAD that are very technically complex: parametric modelling and constraint solving. Parametric modelling is similar to 2D vector graphics formats in that instead of defining where vertices are placed in a coordinate space, it builds the model based on an instruction set that includes primitive shapes like circles but can also include complex curves defined using splines (NURBS)[0]. Constraint solving is a way of mathematically deriving the possible shapes an object can take based on the geometric constraints applied to it. For example, a 2D equilateral triangle could be defined by setting the length of one edge and then constraining all edges to be of equal length. The coordinates of the vertices are derived from these constraints. SolveSpace [1] is an open source parametric modeler with a constraint-based solver that you can explore if this is something you're interested in. [0] https://en.wikipedia.org/wiki/Non-uniform_rational_B-spline https://en.wikipedia.org/wiki/Non-uniform_rational_B-spline [1] https://solvespace.com/index.pl https://solvespace.com/index.pl
moffkalast 3y ago
CAD for artists is just installing a set dimensions plugin for Blender. It's super weird that there's still no native functionality to just scale a select in edit mode to a specific measurable length value.
- mrob 3y ago
  Blender uses an entirely different paradigm: vertex modelling. The only true geometric primitives in Blender are vertices, edges, and faces. When you insert a "sphere", you're actually running code to automatically generate vertices that approximate a sphere. There is no inherent "sphereness" to the resulting object. You have to decide how close an approximation you want up front, and if you get it wrong you might have to redo a lot of modelling. This is particularly tricky when it comes to constructive solid geometry (CSG), e.g. drilling a hole in that sphere by subtracting a cylinder from it. You might not have enough vertices to satisfactorily approximate the resulting object, and have to use various manual techniques to subdivide specific polygons in the right places. CAD supports true curved surfaces. A sphere in CAD is a genuine sphere, and you can decide how accurately to render it independently of your modeling operations. CSG is a core technique in CAD modelling, with no special tricks needed to get good results. To me, the CAD approach is more intuitive, but it's true that vertex modelling can be very fast when you don't need high precision, so I can see why artists like it.
  - moffkalast 3y ago
    Sure, but Blender does support CSG with polygons easily. You can do all typical CAD operations, modifiers, parametric stuff, you just have to pick your accuracy on the fly, not later when exporting. You do realize that everything eventually gets turned into polygons before production right? Well aside from sheet metal design I guess. I've lost count how many Fusion360 modelers I've seen that can't properly turn their models into a mesh and 3D print curved surfaces with visible polygon banding lol. > vertex modelling can be very fast when you don't need high precision, so I can see why artists like it It's not about speed, it's about control. When making assets for rendering all kinds of wild tricks are sometimes needed that go beyond modelling solid objects, plus adjusting UV coordinates for texturing and the like.
gfodor 3y ago
I love this app.
woah 3y ago
I've always used MOI (https://moi3d.com/ https://moi3d.com/) I started something like 12 years ago and always thought it would catch after having to labor through the clumsy paradigm of Rhino in school. Never did catch on, not sure why. Very smooth and intuitive way to sculpt surface models.
- thelazyone 3y ago
  I'm very much torn between Plasticity and MoI for my next sculpting project. I've always used Blender but for some stuff I'm finding myself in need of some proper NURBS tool. I've spent a few hours on Plasticity, I'll do the same with MOI and see how it goes! :)
awhitty 3y ago
The creator of this app, Nick Kallen, has a nice YouTube channel where he talks about some of the behind-the-scenes work on the project. I think his video comparing geometry kernels [0] was posted to HN a while back, but it's worth a watch if you're curious! [0]: https://www.youtube.com/watch?v=WvwiH1DOK1M https://www.youtube.com/watch?v=WvwiH1DOK1M
nylonstrung 3y ago
You mention game devs as potential users. Why would I need NURBS for game models?
thelazyone 3y ago
Currently the only thing that is stopping me from an insta-buy is that the export quality seems to be pretty low poly, even when the detail slider is all the way to 1. Of course my trial version is nowhere near there, but watching several videos it appears that even the highest settings still are far from a proper high-poly export. Since I work with 3D prints, that is a blocking issue for me, BUT the videos are all several months old. Anyone with a more recent experience with Plasticity has something fresher information about that?

103 points by dgellow 3y ago

I’m wondering whether this is useful for 3D printing and whether you can add important measurements when it matters (to make parts that fit.)

CharlesW 3y ago
From a 2022 discussion: https://news.ycombinator.com/item?id=30695360 https://news.ycombinator.com/item?id=30695360 > Are there parametric features? eg. Can I say "this line is 35mm long"? > I want to emphasize to everyone that this is for concept artists. It’s nurbs used to create interesting shapes and fillets. While there are some parametric features, they’re completely de emphasized compared to something like fusion or solidworks
- oktwtf 3y ago
  The software has evolved significantly since 2022, I'd even say that the dev has been flexible and enabled functionality to bridge some more traditional CAD use cases in modern versions. For example when you sketch shapes on a workplane you are able to define the measurement aspects, diameters, offsets, lengths; you can even quickly define relative angles when drawing out segmented lines. However there are no parametric controls for the elements of your shapes or drawings. Keeping these constraints out of mind certainly helps me get into a flow when modeling, much more akin to subd or poly modeling while maintaining the benefits of NURBS. But for adapting models quickly for more flexible designs isn't /really/ the tool for it. You can take it pretty far though! I personally use Plasticity to model all kinds of things including 3d-printed items (vacuum wall mounting, iPhone lens mount, storage cases, clips...) All of these items needed to be measured accurately and Plastiticy was able to handle that without issue. I've been using 3d software for 20+ years, Max, Maya, Blender, XSI, Houdini, Wings3d, Lightwave, Modo, ZBrush, Mudbox... "lots" of 3d software. Some get the job done and some are even a pleasure to use, Plasticity decidedly in my mind does both.
timothyb89 3y ago
I've been using it for light CAD work to design stuff for (hobbyist) 3d printing. You can use exact measurements just fine. The main issue is that it isn't parametric but for my needs that isn't a big issue, and the one-time $150 pricetag is wildly easier to swallow than a Fusion 360 subscription. It's a lot like Blender, if Blender was a few degrees more usable for CAD. That said, I've yet to try the Blender CAD Sketcher addon (https://www.cadsketcher.com/ https://www.cadsketcher.com/).
- declaredapple 3y ago
  Oh I need to try that addon. I've been meaning to look for a Fusion360 alternative that can run on linux and doesn't cost $$$$/yr.
  - graypegg 3y ago
    There's also FreeCAD, which is getting better! Definitely worth trying the RealThunder fork [0] that handles some geometry better than the upstream branch, and is kept up to date. It's still weird. That's for sure. But very much usable as a fusion360 replacement for simple to intermediate 3D printing work. [0] https://github.com/realthunder/FreeCAD/releases https://github.com/realthunder/FreeCAD/releases
    - rcarmo 3y ago
      I try every FreeCAD release in hopes the UX and tool naming improves, but so far no dice. It’s almost amazingly obscure by design.
      - thrtythreeforty 3y ago
        I really want to like it. I am well accustomed to dealing with quirky FOSS UIs. But it is so bad. Something that takes one click in Solidworks or Solid Edge takes ten, and at any point if there is an error, there is no feedback. If it looked like FreeCAD was trying to improve the UI I think I'd be throwing some money their way to fund it. But it appears they're happy with the way it works, as these paper cuts have actually gotten worse over time. It's just FreeCAD, not FOSS-CAD-as-a-whole. Kicad gets better and easier to use each release and I am well aware what a gift it is to engineering work.
bigboy12 3y ago
It’s a really an amazing piece of software.
onthecanposting 3y ago
I use plasticity exclusively for 3D printing. I'm a huge fan. I also deeply appreciate a no-nonsense perpetual license for a fair price. You can't define persistent dimensional or relational constraints; however you can iterate and edit so fast that I have never missed it. Part tolerance is off? Grab a surface and pull it in or out to the length you need. If you need highly parametric parts, I might favor OpenSCAD or CadQuery (python), anyway.

itronitron 3y ago

this link is just an ad

owenpalmer 3y ago
why do you say that?
- fddrdplktrew 3y ago
  I installed a binary but wont register to use it "for free"... I'm going to stick with Blender.
  - cs3f16 3y ago
    Same here
  - owenpalmer 3y ago
    Ah yeah that's a major turn off
- itronitron 3y ago
  I say that because the linked page is just there to get people to download the product and doesn't provide any real information on anything interesting, even though the software itself may be of interest to many people here.
  - dgellow 3y ago
    It’s the landing page of the project…

alted 3y ago

Plasticity is interesting because it is maybe the only way to run the Parasolid geometry kernel natively on Linux right now. Parasolid, the library used to perform the geometric operations (the most difficult and important part of a CAD program) also powers the likes of SolidWorks (the industry standard), NX, and Onshape, and is arguably the best in the world. Its licensing cost is presumably a large part of the Plasticity price.

fsloth 3y ago
Meh. Geometry kernels are oversold. Triangulate, CSG and triumph. CSG is the non-trivial part - and Manifold (https://github.com/elalish/manifold https://github.com/elalish/manifold) is excellent at this. At least for consumer stuff where you anyway eventually just want triangles for either rendering or 3d printing. If your industrial workflow includes CNC machines you may benefit from actual analytic surface cuts and unions - maybe.
Buttons840 3y ago
Why is it difficult (geometric operations)? Do you have any suggestions on how to learn more about it?
- skgough 3y ago
  There are two aspects of CAD that are very technically complex: parametric modelling and constraint solving. Parametric modelling is similar to 2D vector graphics formats in that instead of defining where vertices are placed in a coordinate space, it builds the model based on an instruction set that includes primitive shapes like circles but can also include complex curves defined using splines (NURBS)[0]. Constraint solving is a way of mathematically deriving the possible shapes an object can take based on the geometric constraints applied to it. For example, a 2D equilateral triangle could be defined by setting the length of one edge and then constraining all edges to be of equal length. The coordinates of the vertices are derived from these constraints. SolveSpace [1] is an open source parametric modeler with a constraint-based solver that you can explore if this is something you're interested in. [0] https://en.wikipedia.org/wiki/Non-uniform_rational_B-spline https://en.wikipedia.org/wiki/Non-uniform_rational_B-spline [1] https://solvespace.com/index.pl https://solvespace.com/index.pl

moffkalast 3y ago

CAD for artists is just installing a set dimensions plugin for Blender. It's super weird that there's still no native functionality to just scale a select in edit mode to a specific measurable length value.

mrob 3y ago
Blender uses an entirely different paradigm: vertex modelling. The only true geometric primitives in Blender are vertices, edges, and faces. When you insert a "sphere", you're actually running code to automatically generate vertices that approximate a sphere. There is no inherent "sphereness" to the resulting object. You have to decide how close an approximation you want up front, and if you get it wrong you might have to redo a lot of modelling. This is particularly tricky when it comes to constructive solid geometry (CSG), e.g. drilling a hole in that sphere by subtracting a cylinder from it. You might not have enough vertices to satisfactorily approximate the resulting object, and have to use various manual techniques to subdivide specific polygons in the right places. CAD supports true curved surfaces. A sphere in CAD is a genuine sphere, and you can decide how accurately to render it independently of your modeling operations. CSG is a core technique in CAD modelling, with no special tricks needed to get good results. To me, the CAD approach is more intuitive, but it's true that vertex modelling can be very fast when you don't need high precision, so I can see why artists like it.
- moffkalast 3y ago
  Sure, but Blender does support CSG with polygons easily. You can do all typical CAD operations, modifiers, parametric stuff, you just have to pick your accuracy on the fly, not later when exporting. You do realize that everything eventually gets turned into polygons before production right? Well aside from sheet metal design I guess. I've lost count how many Fusion360 modelers I've seen that can't properly turn their models into a mesh and 3D print curved surfaces with visible polygon banding lol. > vertex modelling can be very fast when you don't need high precision, so I can see why artists like it It's not about speed, it's about control. When making assets for rendering all kinds of wild tricks are sometimes needed that go beyond modelling solid objects, plus adjusting UV coordinates for texturing and the like.

gfodor 3y ago

I love this app.

woah 3y ago

I've always used MOI (https://moi3d.com/ https://moi3d.com/) I started something like 12 years ago and always thought it would catch after having to labor through the clumsy paradigm of Rhino in school. Never did catch on, not sure why. Very smooth and intuitive way to sculpt surface models.

thelazyone 3y ago
I'm very much torn between Plasticity and MoI for my next sculpting project. I've always used Blender but for some stuff I'm finding myself in need of some proper NURBS tool. I've spent a few hours on Plasticity, I'll do the same with MOI and see how it goes! :)

awhitty 3y ago

The creator of this app, Nick Kallen, has a nice YouTube channel where he talks about some of the behind-the-scenes work on the project. I think his video comparing geometry kernels [0] was posted to HN a while back, but it's worth a watch if you're curious! [0]: https://www.youtube.com/watch?v=WvwiH1DOK1M https://www.youtube.com/watch?v=WvwiH1DOK1M

nylonstrung 3y ago

You mention game devs as potential users. Why would I need NURBS for game models?

thelazyone 3y ago

Currently the only thing that is stopping me from an insta-buy is that the export quality seems to be pretty low poly, even when the detail slider is all the way to 1. Of course my trial version is nowhere near there, but watching several videos it appears that even the highest settings still are far from a proper high-poly export. Since I work with 3D prints, that is a blocking issue for me, BUT the videos are all several months old. Anyone with a more recent experience with Plasticity has something fresher information about that?