Repeat things

A hundred rocks, a ring of pillars, a fence that keeps going. You never build these one at a time. You build the shape once, decide where the copies go, and the graph puts one at every spot. Change the shape and all hundred change with it.

When you need this you find yourself about to make the same thing twice.

Two halves, always#

Every repeat is the same pair. Something produces a set of positions, and Instance On Points puts your shape at each one. Swapping the position half changes the arrangement without touching the shape, which is why this is worth learning as two things rather than one.

Circle Points gives you a ring. Scatter Points sprinkles positions over a surface you hand it. Grid tiles an area. Spiral Points climbs, which is how you get a staircase.

Sit the shape down first#

A copy is placed with its own origin at the point. If your shape is centred on its middle, half of every copy ends up underground.

Put a Place On before the instancing, with nothing wired into its Base. It measures the shape and moves it so its underside sits at zero, and it does that at whatever size the shape currently is, so it keeps working when you change the knobs.

Copies are cheap, meshes are not#

Instancing keeps one copy of the geometry and draws it many times. A hundred instanced rocks cost roughly what one rock costs. Joining a hundred separate rocks does not.

This matters most for the thing you were going to do anyway: raise the count knob and see what happens.

Aiming the copies#

Instance On Points has an Orient setting, and it is worth knowing before you need it. Copies can face along the direction of travel (Tangent), which is what bricks and fence rails want, or outward from the centre (Radial), which is what doors and windows in a round tower want, or up along the surface they landed on (Surface), which is what trees on a hillside want.

What comes next#

Right now every copy is identical, and that reads as obviously fake the moment there is more than a handful. Varying them is the next thing.

Joining points up instead of putting things on them#

Everything above puts a copy of something at each point. Triangulate Points does the other thing: it connects the points to each other and hands back a surface, so a scatter becomes ground rather than a place to stand things.

It joins them up as seen from directly above, while the points keep the heights they already had. That is what turns a scatter with varying height into terrain in one node.

Two things to know. It fills in the whole area between the outermost points, so a ring or a horseshoe of points gets bridged straight across; Max Edge Length throws away the long thin triangles that do the bridging. And it wants the points spread out in the view it is looking down (the Axis setting), so two points stacked one above the other count as one.

Grid set to Hexagon through this node gives a lattice of equal-sided triangles, which is a good starting surface when you want something that does not read as square.