# Bend Deform

In this Video tutorial, I will explain how you can use the Bend Deform component in grasshopper. You can easily bend geometry with this tool.

The concept is to make a box and deform it by the “bend deform” component.

You can make a box with different components (Surface> Primitive) but for educational purposes, we will use a plane and extrude it to make the box. You can choose a plane surface from Surface>Primitive. This component asks for a domain instead of width and length. If you connect a number to the X-size (which accepts domain as an input)you can see that grasshopper thinks you mean a domain from 0 to that number.

you can use construct domain (Maths>Domain) to make a more parametric input. If you right-click on the inputs and choose “expression” you can define -x/2 for the start and x/2 for the end. This will make your number the width or length of the plane.

Finally, you can extrude the plane surface in the Z direction to have a box with a controllable hight.

The next step is to bend this box by an arc. You can simply double-click on the canvas and search for “bend”.

Or you can go to the transform menu and select Morph. the “Bend Deform” component can be found in the middle of the list.

The “Bend Deform” has two inputs. The first is the geometry which we will connect the box in to and the second is an arc which will bend our geometry. You can use any kind of parametric arc to deform your geometry (Curve>Primitive). In this video tutorial we will use the Arc SED for the deformation.

The “Arc SED” has a “S”tart , “E”nd and a “D”irection! So we can define the 0,0,0 as the starting point of the arc and give the direction a Z component (just double click and search for Z). For the end, we can give it a point by right-clicking on it and choosing extract parameter and then set point.

By using the grasshopper’s Gumball (Display>Gumball)  we can move the endpoint and have a parametric deformation.

The complete algorithm of the “bend deform” tutorial has been shown below. You can also download the algorithm and give it a try!