Using Geometry Nodes To Create Circular Arrays In Blender 3.0

Creating the Base Geometry

The first step in setting up a circular array with geometry nodes is to create the base geometry that will be duplicated around the circle. For this example, let’s add a simple cube and cylinder that we want to array.

Add a cube to the scene and position it where you want the first instance of the duplicated objects to be placed. Scale and rotate the cube as needed to get the desired shape. The cube will act like our instancer – it defines the position from which the array rotation is calculated.

Next add a cylinder and position it close to the cube. The cylinder represents the object we want to duplicate in the circular pattern. Scale and rotate the cylinder to adjust its shape as desired. Make sure to apply the scale and rotations for the cylinder object before moving on so the transformations don’t cause issues later.

With our cube and cylinder in place in their starting positions, we are ready to set up the geometry nodes.

Setting Up the Geometry Nodes

With our base objects positioned, we can now set up the geometry nodes. Add a Geometry Nodes modifier to the cube object, then open up the modifier panel to expose the node editor workspace.

We need to tell our node tree which objects will be instanced in the array, so first create two Geometry nodes and select the cube and cylinder objects respectively. We will instance the cylinder multiple times based on points distributed around the cube.

Next we need to create an input that allows controlling how many copies are created in the array. Add an Integer node and connect it to a new ‘Count’ input socket. This Count input will determine the number of instances of our cylinder to distribute.

The main node for creating our instances is the ‘Instance on Points’ node. Add this node to the tree and connect the cube Geometry node to the ‘Points’ input, and the cylinder Geometry node to the ‘Instance’ input. The ‘Count’ input determines how many copies are generated.

Distributing Objects in a Circle

With the Instance node set up, we have copies of our cylinder but they are all overlapping at the original location. To space them out in a circle, we need to distribute points around the cube for the instances to be placed on.

Add a ‘Distribute Points on Faces’ node and connect the cube Geometry to the ‘Mesh’ input. This will generate points distributed evenly across the surfaces of the cube. In the node settings, change the ‘Mode’ to Radius and plug the Count input into the ‘Count’ value.

Connecting the ‘Distributed Points’ output to the ‘Points’ socket of the Instance node completes the circular array. The cylinder copies will be spaced evenly around the circumference of the cube, with the number of instances controlled by the Count value.

Rotating the Distribution

Having our instances distributed in a circular pattern around the cube is a good start, but we can gain more control by rotating the distribution.

Add a ‘Rotate’ node and plug the output of the Distribute Points node into it. If we rotate the points before they feed into the Instance node, it will offset where the copies are placed.

Use the Z axis for the rotation to revolve the points around the vertical axis. Plug the output if the Rotate node into the Instance node instead of the Distribute Points node.

By changing the rotation amount between 0 and 360 degrees, we can essentially spin the circular array around to place the copies anywhere we want.

Adding Variation with Randomness

One way to improve the look of the circular array is to introduce some randomness and variation. Rather than having every instance be exactly identical, we can use nodes to alter things like scale and rotation randomly.

Add a ‘Random Value’ node and plug it into the scale of the Instance node. Set the output range to something like 0.8 to 1.2 so the objects will be scaled by a random amount between those values.

Add another Random Value node into the Z rotation of the Instance node. Give this a range of 0 to 360 degrees. Now each instance copy will have random variations in size and orientation.

Extend this concept by chaining together multiple math and random nodes to create variation in position, shape and other parameters for more unique instances.

Animating the Distribution

In addition to random variation, we may want our circular array to animate over time. We can achieve this by animating the rotation value that sets the distribution orientation.

Add a ‘Frame’ input node so we can use the current frame number for our animation. Plug this into a Math node set to multiply, along with a high value like 360 so each frame increment spins the array by 1 degree.

Plug the math node result into the Z value of the Rotate node that sets the instance distribution. Now the array will automatically animate spinning around as the frames progress.

Use the editing context timeline at the bottom of the node editor to scrub through frames and preview the animated circular array.

Final Touches

With the base node setup complete, there are many creative ways to improve the look of the circular array through materials, lighting and rendering.

Try using different materials on the instanced objects like glossy shaders. Add environment textures and use the Material nodes output in the Instance node to randomly assign materials.

Refine lighting with spot, point and area sources to create dramatic effects rotating around the central object. Play with shadows, emissions and volumetrics for bonus flair.

For rendering, cycles offers great realistic shading. For a stylistic look, try using Freestyle to create lines contours around the instances.

As always when using geometry nodes, apply scaling where needed, avoid cycles in node structure, check for unsupported geometry, and debug unusual issues with simple test cases.

Example Node Tree

Below shows an example node setup demonstrating the key nodes needed to create animated circular arrays with geometry nodes.

The critical nodes are the Distribute Points for spacing around a circumference, Rotate for changing distribution angle, Frame input for animation, and Random Values for variation.