# Filling any area with a curved surface?

In the image below, my goal is to fill the circular structure with a smoothly curved surface that seamlessly integrates with the existing contours. How can I achieve this?

• The problem is, if the existing contour rounds up to a flat plane on Y axis, the filling can either also be flat, or inevitably won't merge well with the existing contour. Commented Jul 29, 2023 at 22:58

.. Maybe this is a place for a Cast modifier..

• Cut the object in half, Z-wise
• Grid-fill the hole, perhaps with an I inset first to aid the transition of normals, and keep the mesh density nice and even
• CtrlG assign the vertices in the fill to a new vertex-group:

• Aim a Cast modifier at the vertex-group, 'Sphere', factor 1, with an 'Object' center, an Empty somewhere on (0,0,Z)
• Mirror in Z and adjust:

• Super cool technique!! Thank you! Commented Jul 31, 2023 at 3:27
• @NewBlenderer Ooops! I didn't mean to steal your approval from Harry McKenzie 's perfectly good answer! This one was really for the archive, in case someone needed a bit more precision.. a more adjustable operation, at some expense in speed. Thanks all the same :) Commented Jul 31, 2023 at 6:13
• Now can we do this same to Elliptical shape? What should be the topology of the ellipse before i perform this action? Commented Jul 31, 2023 at 6:34
• I think you might have to resort to Geometry Nodes, to fill the ellipse procedurally with a grid, without deforming the existing flange (thinner in the long axis ticker in the short axis) Commented Jul 31, 2023 at 8:57
• Geo Nodes scares the hell out of me Commented Jul 31, 2023 at 12:09

You can also achieve this geometry by using Proportional Editing.

• Delete the other half of the left over Torus you have
• Select the top Edge Loop and press F to fill in a face.
• Press i to Inset Face
• Hover over the unsubdivided region and press Ctrl+R to add Loop Cuts
• Use mouse wheel to adjust amount of cuts and click LMB to confirm
• Select the center most face and set Proportional Edit to Sphere
• Press 1 or 3 or 7 depending which views the side
• Press G and align along axis (in your case press X or Z in my case)
• Then use your mouse wheel to adjust the size of the proportional influence
• Then apply a Mirror Modifier and optionally a Subdivision Surface Modifier