# Connect vertices where they would meet, not fill?

Lets say I have a plane, and I extrude two edges, it would produce a gap. I would like to fill this gap by using the projected intersection of the new outer edges. Shown in the right most example of the image below:

I can extrude the two vertices and fill the area, making the desired outcome. If I had used F to fill before I've made the vertices meet, the result would be a square with diagonal edges (the empty area would be filled and turned into a triangle, not a square).

For my situation, I am trying to do the same, except I am using a circle. If I simply hit F to join the two vertices I get the result seen on 3. How can I connect the two vertices where they meet (shown in 4). Are there any tools to get the intersection or fill it automatically?

In Blender, navigate to File > User Preferences... > Add-Ons and search for "f2". Enable this add-on:

So now, if you have the following extruded plane:

Select the vertex on the innermost corner of the face you want to create:

Now, press the F key, and the F2 add-on will complete the face, where the vertices should meet:

• This doesn't work on other than square geometry. Jan 13 '16 at 10:55