Materials and appearance

Colour is the cheapest way to make something look finished. A grey model reads as unfinished no matter how good the geometry is, and two colours and a bit of roughness usually do more than another hour of shaping.

When you need this the shape is right and it still looks like a prototype.

What a surface is made of

Set Material decides colour and how light behaves on it. Roughness is the one that matters most: low reads as polished, high reads as stone, cloth or bare wood. Glow makes a surface emit light of its own, which is how panels, runes and screens read at a glance.

See Through does what it says, and it is worth reaching for on glass, ice and anything meant to look thin.

Paint each part before you join

This is the one that costs people an hour.

Set Material repaints everything below it. Put one after a Join and every part that went into that Join comes out the same colour, however carefully each was painted before.

Measured on a door built from panels, glass, bars, a handle and a hinge: a single material under the Join painted all six brown, and six of eleven authored colours never reached the screen. Every swatch still sat in the panel looking live, which is why nobody noticed.

Paint each branch, then join. Never the other way round.

Colour that follows the shape

A single colour is flat. Real surfaces change: dirt at the bottom, snow at the top, rust where water sits.

Color Ramp takes a number for each point and turns it into a colour along a gradient. Feed it height and you get a snow line. Feed it noise and you get patches. Feed it distance and you get a stain that spreads from somewhere.

Keep the number per-point on the way there

The trap is that some nodes hand back a single number rather than one per point, and a chain that passes through one of those loses all its variation.

Height, noise and a comparison all stay per-point. Map Range does not: it returns one value, so putting it between a height and a Color Ramp gives every point the same colour and the gradient disappears.

If a colour that should vary comes out flat, look at what the number passed through on its way.

Faces or corners

A ramp can colour each corner and blend between them, which suits smooth shapes, or paint each face one flat colour, which is the low-poly look.

If flat faces come out looking like triangles rather than tiles, the shape needs its faces declared first, and again after anything that changed its topology.