Procedural Graphene layer

I create this Nodegroup to quickly customize a graphene monolayer. For this one I used the 'array' approach, instancing hexagons side by side in the x and then y directions, then merging them. That's why the geometry looks a diamond shape. To change its center to the origin I simply used a bounding box, dividing the distance from min to max by two and translating the geometry back to origin.