Bulging Sticks: Attractor curve stick pattern

Inputs

Reference in Rhino

Surfaceinput Srf

The surface the pattern is built on. It must be a planar (flat) surface.

Reference in Rhino

Curveinput Crv

The line the bulge follows. It should cross the whole surface, in the direction of the sticks.

Slider	What it changes	Default
Divisions U / V	The number of rows of sticks. More rows means shorter sticks.	1 / 20
Sticks Density	How many sticks are packed into the bulge on each side of the curve.	19
Attractor Range	How far the bulge reaches along each row, on both sides of the curve, as a share of the row length.	0.42
Rectangle Width	The width of every stick. It stays the same everywhere; only the spacing changes.	0.09

Also try: reshape the two Graph Mapper components to make the bulge sharper or softer.

Let the curve cross the whole surface, in the same direction as the sticks. A row the curve doesn’t cross won’t get a bulge.
The sticks never get thicker. Every stick has the same width; the bulge comes from the spacing alone.
Any curve shape works as long as it crosses each row once. A straight diagonal gives a clean bulge; a wavy curve makes it meander.
Balance Sticks Density and Rectangle Width. With a high density and wide sticks, the sticks near the curve merge into a solid band.

How the script builds the pattern. The groups on the canvas follow the same order.

Step	How the script does it
1. Split the surface into rows	`Divide Surface` makes a grid of points. `Flip Matrix` and `Nurbs Curve` join them into one curve per row, and `Extend Curve` lets each row run slightly past the edge.
2. Find where each row crosses your curve	`Curve \| Curve` returns the position of the crossing along each row. That’s the centre of the bulge.
3. Pack the sticks toward the crossing	`Range` creates evenly spaced values. `Construct Domain` and `Remap Numbers` fit them into the stretch just before and just after the crossing, and a `Graph Mapper` on each side bends the spacing so the sticks crowd toward the curve.
4. Keep an even rhythm elsewhere	`Sub Curve` takes the rest of each row, where the sticks stay evenly spaced.
5. Turn the values into positions	`Evaluate Curve` places a point at every value. `Includes` and `Cull Pattern` remove any that fall outside their stretch.
6. Draw the sticks	`Line SDL` draws a line from each point in the direction of the sticks. `Extrude` with `Amplitude` gives it its width, and `Move` centres it on the point.
7. Trim to the surface	`Region Intersection` keeps only what falls inside the surface.

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