My goal is to create something like a "lark's tongue chamfer" along part of each of 4 edges of a cuboid. This would involve a bevel that has a variable depth that forms a smooth curve, starting at 0 depth, reaching some peak depth at the middle, and then returning to 0 at the other side. The main thing is that I would like to know different ways to control the depth as a curve.
Here's an example, sort of following a circular curve, but other shapes ("smooth", "sphere", "root", etc) would be desirable:
I've created this mesh, but my procedure was long and convoluted, and I'm sure there's a better way someone can suggest.
Additionally, can someone clarify for me: (a) Is there a name for this sort of bevel, chamfer, or shape in general?; (b) Later I want to round off all of the sharp edges (i.e. with a tiny bevel) and I want to (say) subdivide the surface to smooth it out, and for this I understand it might be important to avoid having the triangles shown in my image above, so what should be done about this?
Anyway, below is what I did, including screenshots of key steps. Apologies if the screenshots are not very clear at their default size, but the image itself is available as a larger version. Note that units are in metres...
- Image A: Create a 2-metre plane, and go into Edit mode. Subdivide the face 8 times, creating a sheet as a 9x9 grid
- Duplicate and move up by a known fixed amount on Z axis (e.g. 0.2m)
- Image B: Repeat, duplicating the sheet copy that was made in step 3
- Image C: Select the edge loop of the top-most sheet, then hide all but this selection (SHIFT+H). Go to top view, then select the middle-most edge segment of one side
- Image D: Turn on Proportional Editing, set to "Sphere" mode. Move the selected edge inwards (i.e. on the X axis only) by 0.1, setting the proportional size to (say) 0.55
- Image E: Repeat with the other 3 sides
- Image F: Unhide everything with ALT+H. Select everything in the middle sheet now
- Image G: Hide everything else with SHIFT+H. Go to top view, then select and delete all interior edges, leaving just the square outline edges. Select the middle edge of each side of the square
- Image H: Go to side view and then move these edges again, this time down by -0.1 on Z axis with proportional size still the same as above
- Image I: Unhide everything with ALT+H. Select all edges of the top sheet
- Image J: Move the top sheet down to superimpose it on the middle sheet (making sure to turn off proportional editing)
- Image K: Select the edge loops of the top sheet, and also the edge loops of the middle sheet
- Image L: Click RMB and select "Bridge Edge Loops"
- Image M: Select the edge loops of the middle sheet, and also of the bottom sheet, and then Bridge Edge Loops there, too
- Image N: Select all, and then Mesh => Cleanup => Degenerate dissolve. Fix normals with SHIFT+N. Deselect all, and we're done!