I have a triangular space I want to fill with Grid Fill. The two long sides have each 33 vertices. So connecting them should give the vertical edges of the grid. The short side (on the left) has seven vertices. There should be 7 horizontal grid edges radiating to these vertices from the triangle point. How can I make Grid Fill do this?
Create a edgeloop on the other side
Starting from a similar situation
Just model the last face picking the last three vertices and press F.
Then subdivide the internal edge a with the same nuber of cuts of the vertices on the opposite side.
Now you can run the Grid Fill command
Note: the accuracy of the interpolation on the triangular tip depends on the size of the face, but nothing prevents you to subdivide the edges and make a tiny temporary face that at the end will be collapsed in one point.