This material is an attempt to produce a plaid fabric pattern from within the material room. It demonstrated two principles of the material room. One is that the complexity of a material can be built up in simple steps, with each node providing one aspect of the final pattern. The second is the idea of the control node, in this case a maths node used to control fourteen related settings!

Fig 1: Plaid

This material is based on the Tile node. In order to produce a more complex pattern, a series of tile nodes are plugged into each other, each one providing a new layer to the pattern. The first tile node is plugged directly into the Diffuse Color input. This node provides the red stripe, the top layer of the pattern. The two tile colours are left white, so that we can plug our second tile into them to put the next layer in the plaid.

This is the key to this material. Each tile provides a new mortar colour, or stripe. Changes to the mortar width, the tile size and the tile offsets provide the pattern. Figure Two shows a close up of the eventual result. Tile one is providing the red stripe, offset so that it falls between other parts of the pattern. Tile two provides the thin yellow stripes. Tile three provides the wider green strips. It is almost identical to Tile two, but with a thicker mortar, so that the green is visible behind the yellow. Finally, Tile Four provides the two tone blue background, once again offset so that it falls between the other patterns. Each tile fills in the gaps left by the previous one.

Fig 2: The Colour Grid

The node setup is not a complex as it looks. The basis of it is the four tile nodes. In each case, the output of one node is plugged into the Tile colour inputs of the next. The sizes and offsets are designed to work on this particular object - other objects with different UV mapping might need different settings. The Maths node is there to make it easier to control the scale of the final output. It is plugged into every input that controls the final size. This way, if you decide that you need the plaid to be half its current size, all you have to do is alter the Value_1 of the maths node.

The final quality of this material is very dependent on your quality settings. It works much better with a minimum shading rate of under 1. Above that, it can be quite jagged, especially at smaller sizes.

To appreciate how this material works, I'd suggest that you create it tile node by tile node, rendering after you've added each tile, so that you can see how the pattern is built up. I will be returning to the basic concept of tile stacking in later articles.

Fig 3: The Node setup