[Grasshopper] How to use Region Union to merge intersecting areas of closed curves and plane surfaces

This article explains how to use Region Union to merge intersecting areas of closed curves and plane surfaces.

On the Grasshopper, it is represented by either of the two above.

Table of Contents

For closed curve and line data

Using Region Union, you can add and combine closed curves or planar surfaces by performing Boolean operations on their union.

First, let’s look at the case of closed curve and line data.

Components used: ① Rectangle ② Circle ③ Region Union

In the first example, we’ll create curve and line data for a square and a circle and try adding them together.

Enter the numerical value for the length of one side into the Rectangle(X and Y).

This time, since 1000 was entered, a 1000×1000 square was created.

Additionally, enter the radius value into the Circle(R).

This time, since 500 was entered, a circle with a radius of 500 was created.

Next, connect the Rectangle(R) to the Circle(C), and then connect the Circle(C) to the Region Union(C).

Then, the curve and line data were added together and combined.

Next, let’s look at the case of surfaces.

Additional Components: ① Surface

Insert a Surface between the Rectangle and Circle from earlier.

Then it will be converted from a closed line to a surface.

Then, the surfaces were added together and merged like this.

However, even when executed for a surface, it will be output as line data.

To convert to a surface, connect the Region Union to the Surface.

Then, the combined line data was converted to a surface.

Additional Components: ① Series ② Unit Z ③ Move ④ List item ⑤ Plane

This time, we’ll copy multiple squares and circles directly upward and specify a single plane.

Enter 500 into the Series(N) and 10 into the Series(C).

Then, ten numbers are created, increasing by 500 each time: 0, 500, 1000, …, 1000.

Then connect the Series to Unit Z.

Additionally, connect Unit Z to the two Move(T).

Also, connect the Rectangle(R) and the Circle to the Move(G), respectively.

Then, a square and a circle were copied directly upward, creating 10 sets.

Next, connect the Rectangle’s Move(G) to the List Item(L).

Then, enter the number 4 into the List Item(i).

Then, you can only obtain the fifth square.

Then, connect the List Item to the Plane.

This allowed us to obtain the plane data for that location.

Then connect the Plane to the Region Union(P).

Furthermore, connect the two Move(G) to the Region Union(C), respectively.

Then, only at the specified plane position, the addition operation was performed, combining the square and the circle.

List of Grasshopper articles using Region Union component↓