Is there any way of converting the triangle fan found on a cylinder cap into quads.
If you know that your circle has a even number of vertices, and do not care how the gird is aligned; then select all the vertices in the circle with alt RMB , then ctrl F > grid fill.
Select half of the vertices of the circle. The selection needs to have the same number of vertices along the top and bottom, and the same number unselected on the side.
Then press ctrl F > grid fill.
Which will give you this.
$\begingroup$ The number of selected vertices in one loop needs to be odd to. $\endgroup$ Jul 31, 2014 at 15:48
$\begingroup$ @user877329 I'm not sure what you mean. $\endgroup$– DavidJul 31, 2014 at 16:09
$\begingroup$ I found that there was a vertex left in the middle that caused the operation to fail. $\endgroup$ Jul 31, 2014 at 16:13
3$\begingroup$ Grid Fill also works if you select the entire loop, but not if there is an odd number of vertices. If the number is odd, it will give an error message saying "Select two Edge Loops." Alt-V now adds the ability to quickly splice in the extra vert that is need, or instead, you could dissolve one vertex. $\endgroup$ Jul 31, 2014 at 16:14
3$\begingroup$ Things often happen quick on this site. $\endgroup$ Jul 31, 2014 at 16:24
If you intend to subdivide the mesh later (eg. using Subsurf modifier) and use only Grid Fill on the cap, you will get distorted mesh, despite the fact that it's all quads.
In such situations caring about all quad faces is not enough and filling the gap with simple Grid Fill operation won't do the trick. You need at least one additional edge loop on the cap before using Grid Fill, like the mesh on the right shows:
AltJ will convert triangles to quads where possible. For good topology and efficient geometry, you can use grid fill but then you should change the Span value to 1.
Click the image see it at full size. Current as of Blender 2.72b
$\begingroup$ Interesting option! Mightn't be feasible always but definitely an option in some situations. You'd still end up with a pole at the centre though. $\endgroup$ Jan 10, 2021 at 7:56