How Can I Turn a Right Angle Into a Quarter Circle?

Question

In trying to fix the n-gons and tris on a mesh, I've run into a problem where I need to turn a set of vertices that forms a right angle into one that forms a curve.

You can see that most of my edge loops have a curve to them, except for the innermost loop (which has the pole I'm fixing at the corner of the right angle). All the vertices for each loop share the same z-coordinate. I'd like to just turn the selected points into a curve, then scale them so they follow the curve of the other edge loops and dissolve+recreate the edges to fix the topology. But I can't figure out how to do this.

I've drawn what I'm trying to do in blue (curve the vertices and re-do the edges). I'd be happy with a quarter circle of any radius as long as the vertices were properly distributed.

Answer 1

I'm a bit confused on what exactly you are trying to do. Do you intend on adding those blue vertices to the existing edges so they connect to the corner afterwards or do you want the whole corner to be much bigger to follow the curvature of the blue line? Either way I don't think that would simplify it at all. If you want to have nothing but quads on that corner point you can merge 2 side-by-side triangles like this:

But in general, for cleaner geometry, you'd want to remove all those parallel edges on the sides of the corner. They aren't really doing anything there. Even if you have something like a round hole in the top face that they are connecting to, it's probably better to use some triangles to decimate that mesh. They are usually not going to look bad if it's a flat face that doesn't deform, like ngons

If you want to modify that one merge vertex into multiple for whatever reason you can move the cursor to it, then select it and use ctrl+Shift+B to bevel it. Part of the vertices will move down so you'll have to flatten the created face with the others as the transformation point:

You can them move it so that it's position in a way that the cursor is on top of what would be the corner if it wasn't beveled. You can eyeball it or you can create an auxiliary vertex aligned with the others to be the corner and move that in to the cursor:

You can then use the cursor as the transformation point to scale it to whatever size you need.