First method, using a Lattice and Lattice modifier.
- Set the interpolation to Linear in the lattice properties.
- Scale the Lattice in Object mode so it encompasses the wall object.
- Go into Edit mode, and scale the top 4 vertices along the XY plane.
Second method, with a Simple deform modifier. Use a negative value to taper "down" your object.
I added an empty at world origin so the taper is centered, and used it as the modifier origin.
Third method, Geometry Nodes (V2.93+):
Basic steps of the modifier :
- Add a GN modifier to the object.
- Add a Transform Node to recenter the object (might not be needed if you changed the origin).
- Add an Attribute Separate XYZ Node to retrieve the X, Y, and Z components of each vertex' position.
- Add an Attribute Math node to downscale the Z attribute which we will use to taper the object.
- Add an Attribute Combine XYZ node to combine the X and Y components which we will use to taper the object.
- Use an Attribute Mix node set to subtract the X and Y components to the vertex' position, using the Z position as a factor.
- Use a math node to downscale the Z factor before it is applied
- Plug a new input into the math node.