How to move vertex along edge?

For example, there are 3 vertices on a straight line, ie A, B and C. How to move B along the edge only? It is easy for a vertical or horizontal edge, but what about a leaned line? thanx.


Put the cursor at “a” or “c” and then with the pivot mode set to cursor scale point “b” to where you want it to be.


Set the scaling so that it is done with respect to the 3D cursor(press the dot (.) key). Select one end vertex. Shift S cursor to selection. Select the vertex you want to move, S to scale it and it will move in line with the edge.