Knife Topology Tool in Blender 3d
The Knife Topology Tool lets you interactively “cut through” faces, subdividing them and creating a chain of new edges along the way. The Knife topology tool is a very useful and practical tool.
How to use Knife Topology Tool?
First, select the tool in the Toolbar or press K. The cursor will change into a scalpel to indicate it’s active.
Click LMB at the place where you want to start cutting. This can be anywhere: on an existing vertex, edge or face, or even outside of the mesh.
Move your mouse to the next location. You’ll see a purple line indicating the new edges that will be created, and green squares indicating the new vertices. Click LMB to confirm: the green squares will turn red, and you can define the next line in the cutting path.
Once you’re done, press Spacebar or Return to apply the cuts. Alternatively, press Esc to cancel.
More information is here: Knife Topology Tool
