Round Cube: real Quadsphere, Capsule, Rounded Cuboid, 3D Grid + Convex Hull Margin

Here are two Add-ons:

Round Cube is a multi-purpose mesh primitive.

Being a mathematical sphere, the corners are not pinched, bevels are round, and polygon face sizes are more balanced (more uniform polygon surface area) than other methods (e.g. subdivision surface + cast or bevel modifiers).

The add-on can also produce any size (x, y, z) capsule or cuboid. One of the disadvantages to consider is that non-spherical objects produced by this add-on will not scale well non-uniformly after they are generated.

Hover over the operator parameters for a description of their use. Note resulting size is the largest of either radius (of vertices) or size (by axis).

UVs are easily created using the Follow Active Quads option to get a cross map.

One of the primary purposes for this add-on is to produce good primitives for sculpting.

Some example meshes it can generate:

Some examples demonstrating the “Division Type” parameter:


I suggest using All for sculpting.

This add-on started from a much more simple Convex Hull Margin add-on I had written over a year ago but didn’t get around to releasing (I did release C++ code for Bullet). I decided to clean up the original and release it, but wasn’t sure if anyone would have any use for it, so I also took some time to write this more general purpose Round Cube one.

So the Convex Hull Margin add-on will produce an approximate convex hull either shrunk or expanded by a specified margin from a selected object, with, or without bevelling. For examples, see the following video; the bevelled collision margin visualizations are all expanded by a margin, i.e. 0.25 (you could use it to bevel a Cone, for example):
Bullet Physics Collision Margins and Shapes

Hopefully someone finds these useful. I’ll answer questions below.

1 Like

…long waiting for similar primitives > thx for sharing!..

nice work, I could use these in add mesh extra objects addon.

really nice! thanks for this:)

sweet, ported to Sverchok immediately!

if you want to see:

thanks,useful addons

Thanks for the feedback. Updated to v0.2.1 with minor bug fixes and clean-up on first post.

I think the Round Cube add-on is pretty much done now. I’ve removed the menu presets in favor of the Blender built-in preset mechanism to alleviate the menus. I’ve added a wiki and submitted it, see first post for wiki link (contains link to download latest round cube add-on version + presets / task).

On the subject of additional primitives, I would like to propose an option for the UV sphere where the poles are not represented by a single vertex but as many vertices (coincident) as latitudinal divisions, in order to make the resulting mesh quad-only.

It would make the job of creating UV mappings for equiangular images trivial (purpose: skyspheres, planets).

thanks for the perfect lessons in blender riggid bodys. could you please update the Object: Convex Hull Margin download link. it´s somehow gone.

Sorry for the delay, I forgot about the expiring links.
I’ve decided to update the Convex Hull Margin add-on for Blender 2.74 and I’ve uploaded it to the Bullet Physics Forum (hopefully Erwin doesn’t mind) for now. It shouldn’t expire there, I’ll see if this bmesh version survives future Blender updates, hopefully I’ll post it properly with a wiki page in the future.

hi, round cube addon has been accepted & merged into add_mesh_extra_objects replacing old polysphere addon.
http://wiki.blender.org/index.php/Dev:Ref/Release_Notes/2.75/Addons
Please send updates here: https://developer.blender.org/maniphest/task/create/?project=3&type=Patch

Thanks very much.

Thank you Meta-Androcto, but it appears the add-on used was not the one officially submitted? It appears to be based on the very first working copy (with some bugs) posted on this forum last year Sept.10 instead.

I officially submitted only a single version of this add-on last year Sept. 17, here: https://developer.blender.org/T41859

Thanks.