Live data from Hacker News

Plasticity Is CAD for Artists

github.com

11–20 of 109 posts

Re: Plasticity Is CAD for Artists

#11

For those of us who are not familiar with the domain, what differentiates this from Blender? Does Blender not support NURBS? If not, why is that the case?

On a higher level:

A 3D editor mainly intended for visual pipeline such as Blender, and a modeling application intended for producing physical shapes have entirely different constraints and intents. They both operate on 3D data, but it's best to leave it at that.

If we use text files as an analogue, then the "3D" feature in these applications is roughly a similar unifying feature as "text based input" in programming languages - or in all programs for that matter.

For text files, you want it to have specific encoding - e.g. UTF-8. For 3D shapes, you want the data to similarly follow a mathematical schema with specific topological constraints.

If you break the convention of the encoding, or the schema, you produce gibberish.

With a specific standard in place some parts of input data may or may not be transferrable between domains (e.g. CSV data is kind of lingua franca) and lots of interesting things can be built on top of that.

But generally you could ask "how is this different from" X where X can be for example Excel or Photoshop - the answer is very complex.

Re: Plasticity Is CAD for Artists

#12

For those of us who are not familiar with the domain, what differentiates this from Blender? Does Blender not support NURBS? If not, why is that the case?

Blender does support NURBS but very basic and very limited to the point that it's not very useful.

Basically there are 3 methods for creating 3D content:

  * Voxels (points in space)
  * Polygon (vertices, edges and faces)
  * Mathematically calculated (NURBS, CAD)
Blender uses all three but focusses on polygon modeling (triangles).

The real pro of NURBS mondeling is that you are working with surfaces that can easily be shaped. That's why this method is used a lot in product development. Since all surfaces are calculated they also are infinite smooth. When you want a smooth surface with polygon modeling you need a lot of triangles.

For each category there are different tools, Blender is just one of them.

Some examples of software products per category:

  product design: Rhino
  car design: Alias
  house design: Revit
  technical components: Fusion 360
  game assets: Blender
  sculpting: Z-Brush
  movie GFX: Houdiny

Re: Plasticity Is CAD for Artists

#13

For those of us who are not familiar with the domain, what differentiates this from Blender? Does Blender not support NURBS? If not, why is that the case?

Blender does support NURBS but very basic and very limited to the point that it's not very useful. Basically there are 3 methods for creating 3D content: * Voxels (points in space) * Polygon (vertices, edges and faces) * Mathematically calculated (NURBS, CAD) Blender uses all three but focusses on polygon modeling (triangles). The real pro of NURBS mondeling is that you are working with surfaces that can easily be sh…

Very informative, thank you

Re: Plasticity Is CAD for Artists

#14

For those of us who are not familiar with the domain, what differentiates this from Blender? Does Blender not support NURBS? If not, why is that the case?

> what differentiates this from Blender?

NURBS support in Blender is very minimal and nowhere near what real NURBS modeling packages can do.

For example, Blender can't even import STEP or IGES natively while even FreeCAD can.

Re: Plasticity Is CAD for Artists

#15
A side note not intended as hostile or disparaging for any stakeholders:

Plasticity seems to use c3d toolkit for it's solid operations.

That may - or may not be - soon problematic as the company that produces is based in Russia (https://c3dlabs.com/en/company/about/).

Are other c3d users finding this problematic? There aren't that many solid kernels in the market.

Re: Plasticity Is CAD for Artists

#16

Earlier quoted context omitted.

This is really cool, both in terms of what it can do, the approachable pricing model and the video that shows it off. (Since I’m not aware of the details…) Is this similar to using NURBS as the representation in Blender? As in what makes this more CAD-ey?

Blender as a tool is very far from CAD-ey, in the sense that precision work - this should be 120 mm and that should be 1.41 times this - is not really a supported workflow. There isn't even a constraint solver in Blender. You can make Blender work as a CAD-ish tool with practice and self-discipline and lots of keyboard shortcuts. But e.g. Fusion360 or even SketchUp is what a CAD-oriented workflow feels like. There is…

> There isn't even a constraint solver in Blender.

Not 100% correct. There are a number of add-ons that do this. I even think someone managed to hook-up the solvespace engine in a blender add-on

There are also a whole slew of add-ons that can make Blender more CAD-friendly.

However, you are correct, this is not the primary intent of Blender.

Re: Plasticity Is CAD for Artists

#17
post #7

> Plasticity is mostly Open Source. When Plasticity reaches 1.0, it will cost $25 to use (no subscription). I'm curious how this will be implemented. According to the LICENSE file in the repo, the current source is available under LGPL. What will cost $25? Will the repo be taken off-line after 1.0 release? Or will further updates after 1.0 be binary only?

It appears to use C3D as its CAD kernel, which is proprietary. You can't build it without a copy of C3D. I'm guessing the source will be available for inspection, but the binary will cost money.

Re: Plasticity Is CAD for Artists

#20
post #7

> Plasticity is mostly Open Source. When Plasticity reaches 1.0, it will cost $25 to use (no subscription). I'm curious how this will be implemented. According to the LICENSE file in the repo, the current source is available under LGPL. What will cost $25? Will the repo be taken off-line after 1.0 release? Or will further updates after 1.0 be binary only?

you may sell binaries of GPL licensed code. red had is doing it, while the redhat source is available for free. (which is how centos and now rocky linux and others are made)
Post reply on HN