How can I draw a porous particle?

Question

I want to know how to model a porous particle that has a solid or hollow inner space. I want to know how to control the surface thickness in case of the hollow particle.

I found a tutorial, Porous Particle in 3D Graphics –Let’s Shade 3D #006, but it's made by another software.

The second question is: How can I cut a triangle from the particle to illustrate what is inside?

Examples of hollow, solid, porous particle and a cut particle.

Answer 1

Hey guys ... you provoke me :)
No deformations on surface. No glitches in animation with booleans.

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Shape 01

• add Icosphere
• Bevel Ctrl+B Vertices V
• Delete X newly generated faces

Modifiers:

• Subdivision - Level 2
• Cast – Sphere, Factor 1 (to get perfect sphere shape)
• Solidify for thickness
• Boolean - to cut quarter by another object like a Cube

Notes: Switch to Edge or Face select mode before bevelling so newly generated faces stay selected. For boolean use Exact solver. Smooth shading is used with enabled under Properties Editor > Data Properties > Normals > Auto Smooth.

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If you need more dense holes just increase Subdivision to 3 in step one (add Icosphere) in Properties panel (left-bottom in View3D editor).

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Shape 02

For version with vertical holes it is a bit more difficult...

• Add Plane, Subdivide W a few times and as before ...
• Bevel Ctrl+B Vertices V
• Delete X newly generated faces

• Add Sphere
• Add Shrinkwrap modifier to Plane with Wrap method > Project, Target > Sphere and Apply modifier

• At a bottom delete corners, select border vertices and search for To Sphere Shift+AltS set 1 to get edge circular. Alternatively you can add one extra Loop cut Ctrl+R
• Select holes by Loop Select Shift+Alt click on edge in Edge select mode (not Vertex select mode) each hole, Extrude E a bit in Z axis Z, Extrude again in Z much more, Scale in Z to zero and move vertices to Z Loc zero
• Create a Vertex Group from outer surface (without tubes)

Modifiers

• Subdivision - Level 2 (to keep holes sharp - exclude edges by Shift+E press 1)
• Cast - Sphere, Factor 1, Radius 1.02, set Vertex Group of outer vertices (you created before) to let modifier affect sphere without tubes
• Mirror - only in Z

• Boolean - use a Cube to cut

Answer 2

1. Create icosphere + cube

2. add subdivision modifier to icosphere

3. add boolean modifier to icosphere -> object: cube

4. select icosphere and enter edit mode with TAB

5. press CTRL-B to bevel and bevel like this:

6. change to face select

7. select one circle face

8. select->select similar -> polygon sides

then you will get:

9. Tap X -> Faces

10. press TAB

11. Shade smooth

12. select the cube and change viewport display to bounds

13. move the cube over the sphere as you need it

Result:

of course you can give it a solidify modifier, as vklidu said, looks even a bit better:

Answer 3

Let's try with, hated for good reasons, boolean workflow, mainly because I think the tutorial you linked uses booleans. Though there the holes aren't distributed evenly:

The above could be achieved by making a cone, and adding two array modifiers, but we can do better, like Chris, so let's try but with boolean modifier.

The advantage of boolean is that you don't have to go through a puzzle on proper topology, so this solution should be more versatile (e.g. when you want to replace the cones with cylinders as on one of your reference images). The disadvantages are, however, plenty:

• the resulting topology may be very heavy (a lot of triangles)
• booleans are often buggy and cause issues with animations due to inconsistency
• there are also problems with smooth shading and resolving them can be quite tricky (normal data transfer from the original uncut sphere)

Add an Ico Sphere (because that generates equally spaced triangles), then add a cone, edit it, using Increment Snapping (hold Ctrl or click the magnet button) move the cone so that the tip is at the world (sphere) center. I also move the base up because I find it more natural to look an an object from the top, but that's just my preference. Then I rotate the cone to make it roughly fit a triangle (keep in mind in this situation you have to rotate along green Y axis, not red X axis, due to how the triangles are distributed). If you readjust the distance of the base of the cone to the center, remember to use G, Z but in local coordinate space, ignoring the rotation of the object.

Let's name this cone Cone.A, and duplicate it, and name the duplicate Cone.B, let's also Hide Cone.B for now. Likewise rename the Ico Sphere to Ico.A, and create a duplicate Ico.B, hide the latter.

Select Cone.A, then Ico.A, Ctrl+P, O.

Edit the Ico.A, select the triangle overlapped by the cone, Shift+S, U:

Now in object mode, with the Cone.A selected, press F3 and search for Set origin to 3D cursor. In Numbers panel, clear (set to 0) cone's rotation as well as location, so it's inside the sphere, then with Ico.A selected, change its instancing to Faces:

And we got the cones:

Though there's still some room for additional cones - exactly where the Ico Sphere's vertices are... So let's hide the Ico.A and Cone.A, unhide the Ico.B, Edit the mesh, select everything, Ctrl+B for bevel, scroll down (mouse wheel) for minimum number of edges, C to clamp, and move your mouse to maximize the bevel like so:

M, B, increase the range until you remove all small faces:

Adjust Cone.B to the top face of Ico.B just was done with A variant. Don't resize the cone, though. Result:

I'd advise hiding both sphere, going into edit mode of each cone, hiding everything except the base face, then in object mode unhiding everything, selecting both cones, going to edit mode, and then scaling the bases so they have satisfying size:

Select Cone.A, Ctrl+A, M (Make instances real), Shift-click one of the cones to activate it, Ctrl+J to join those cones into a single mesh/object. H to hide it. Repeat for Cone.B. Remove the rest. Unhide the cones, select both, Ctrl+J to join them. Now you have the equivalent of the first screenshot in this post.

You can now create a "proper" sphere to your liking, e.g. UV sphere. You can add another sphere to cut the insides of the main sphere, you can add a cube to cut a fragment of the resulting shape... Once you're done, Hide the cones, as well as other objects you use for cutting (or change their display to bounds, as I did for the inner sphere and the cube) and add boolean modifiers like so (before doing so better save your project :D):

And here's an underperforming animation, notice the bugs...