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I am trying to make a sphere with holes/bumps, with good retopology. How to get sphere like in Picture? Sphere with ~20 holes. Without Boolean modificator.

I tried IcoSphere/Sphere with = Ctrl+B - V. But i get or 12 or 32-40 round holes. But i need ~20 rounds/holes (+/- 2) enter image description here

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    $\begingroup$ Hello, in your picture it looks more like bumps than holes $\endgroup$
    – moonboots
    Jan 5 at 18:18
  • $\begingroup$ the holes must be inside... :D $\endgroup$
    – Chris
    Jan 5 at 19:42
  • $\begingroup$ @AlmasIskak You only have 2 choices of the regular solids ( Platonic Solids ). Either go with a Dodecahedron (20 vertices and bevel each vert with ctrl+shift+b) or the Icosahedron (20 faces and inset each face). Then use the same procedure as shown in Robin's answer. You can easily create a dodecahedron using the same addon used in this thread and the Icosahedron using Mesh > Ico Sphere with 1 level subdiv $\endgroup$ Jan 6 at 7:05

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The base topology of this looks to me like a Geodesic Dome, or Bucky-Ball. This can be reached vis the shipped Add Mesh: Geodesic Domes add-on, or by taking the dual mesh of a base Icosphere. The dual can be created in Geometry Nodes, or via the shipped Tissue add-on.

This shows the dual mesh, simply subdivided, and then with the central pole vertices CtrlShiftB bevelled out to inner faces:

enter image description here

enter image description here

The inner faces have further:

  • Had their edges Bevel Weight set to 1.
  • Have had the shipped Add-on: Loop Tools > Circle applied to them, with 'Radius' set, so they are all the same size.
  • Been assigned to a Vertex-Group ('Dome').

At this stage, the inset faces were UV unwrapped, by 'Reset'. This means all those face's UV's are centered in the UV space, with the same area. The remaining faces were scaled to 0 in a corner.

The faces were then repeatedly I inset (with a further I to set 'Individual')

I found 2 vertex-groups helped keep control, one for the raised domes (left), and the other for the region of the mesh supposed to remain spherical:

enter image description here

Now the rest can be done with modifiers.

  • A Cast > Sphere modifier, open to adjustment further down the line, possibly aimed at the second vertex-group, above
  • A Displace modifier, aimed at the left group, above, using a Blend > Spherical texture, in the space of the reset UV Map
  • A Bevel modifier, by the edge-bevel weights we set earlier, to sharpen the edges of the domes, where they meet the sphere
  • A Subdivision Surface modifier.

The result, and its topology:

enter image description here

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  • $\begingroup$ Hi Robin I added a gif on how to create the dome I hope I didn't make a mistake, for the newbies to see detailed steps. $\endgroup$ Jan 6 at 3:40
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    $\begingroup$ Hi! Thank U very much,i really appreciate it! But u see, there are 40 bumps/holes in this model. But before i mentioned, i need ~20 bumps/holes (+/- 2). I made exactly this before, and get or 12 or 40 bumps/holes. So there is a problem in amount of bumps... (( $\endgroup$ Jan 6 at 4:13
  • $\begingroup$ @AlmasIskak You only have 2 choices of the regular solids ( Platonic Solids ). Either go with a Dodecahedron (20 vertices and bevel each vert with ctrl+shift+b) or the Icosahedron (20 faces and inset each face). Then use the same procedure as shown in Robin's answer. You can easily create a dodecahedron using the same addon used in this thread and the Icosahedron using Mesh > Ico Sphere with 1 level subdiv $\endgroup$ Jan 6 at 7:08
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    $\begingroup$ @HarryMcKenzie that's a Blend -> Spherical texture, put through a colour-ramp to cheat the curvature. But with a regular solid, it's maybe more easily, although more destructively, possible with prop. editing, rather than Displacement modifier, since all faces identical? Go ahead and do it in 2 ridiculously simple moves :D .. $\endgroup$
    – Robin Betts
    Jan 6 at 8:16
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    $\begingroup$ Hi, @AlmasIskak This is the best I've managed so far. Still shows very slight pinching under Subdiv. It started with an icosahedron . I got tired of getting Cast to be predictable, so made my own little GN version.. feeling my way through, hard to make into a concise answer. Here it is: blend-exchange.com/b/KAwrD0V5 $\endgroup$
    – Robin Betts
    Jan 6 at 17:29

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