Built-in Catalog

packages/patterns/src/patterns.ts ships twelve built-in patterns, registered in PATTERN_GENERATORS in the exact order below. Every pattern follows the generator contract: deterministic, mm-space, and clamped through resolveParam against the ranges listed here. pitch/cell/size/width/lineWidth/radius/amplitude/wavelength params are all in millimetres; count is a unitless ray count; centerY is a unitless 0–1 fraction of the panel height.

Parameter reference

Pattern (`name`)	Draw style	Parameters (`key` — range, step, default)
Dot Grid (`dot-grid`)	fill	`pitch` 2–15mm, step 0.5, default 5; `radius` 0.2–4mm, step 0.1, default 1
Diagonal Stripes (`diag-stripes`)	stroke	`pitch` 2–20mm, step 0.5, default 6; `lineWidth` 0.3–10mm, step 0.1, default 2
Grid Lines (`grid-lines`)	stroke	`pitch` 2–15mm, step 0.5, default 5; `lineWidth` 0.1–3mm, step 0.05, default 0.4
Concentric Circles (`concentric-circles`)	stroke	`pitch` 1–15mm, step 0.5, default 4; `lineWidth` 0.1–4mm, step 0.05, default 0.6; `centerY` 0–1, step 0.05, default 0.5
Hex Lattice (`hex-lattice`)	stroke	`cell` 2–20mm, step 0.5, default 6; `lineWidth` 0.1–3mm, step 0.05, default 0.5
Checker (`checker`)	fill	`cell` 1–20mm, step 0.5, default 5
Wave Lines (`wave-lines`)	stroke	`pitch` 2–15mm, step 0.5, default 5; `amplitude` 0.5–8mm, step 0.25, default 1.5; `wavelength` 3–30mm, step 1, default 12; `lineWidth` 0.1–3mm, step 0.05, default 0.6
Crosshatch (`crosshatch`)	stroke	`pitch` 2–20mm, step 0.5, default 7; `lineWidth` 0.1–4mm, step 0.05, default 0.5
Radial Burst (`radial-burst`)	stroke	`count` (rays) 8–96, step 2, default 36; `lineWidth` 0.1–3mm, step 0.05, default 0.5; `centerY` 0–1, step 0.05, default 0.5; `innerRadius` 0–30mm, step 0.5, default 4
Brick (`brick`)	stroke	`brickW` 3–30mm, step 0.5, default 12; `brickH` 2–15mm, step 0.5, default 5; `lineWidth` 0.1–3mm, step 0.05, default 0.4
Diamond Lattice (`diamond-lattice`)	stroke	`size` 3–30mm, step 0.5, default 8; `lineWidth` 0.1–3mm, step 0.05, default 0.5
Scallops (`scallops`)	stroke	`width` 3–30mm, step 0.5, default 10; `lineWidth` 0.1–3mm, step 0.05, default 0.5

Note

resolveParam clamps every value into its declared [min, max] before a generator uses it, so a stale or hand-edited params value (e.g. from an imported order JSON) can never send a draw loop negative or non-finite. See Generator contract → Param clamping.

Pattern notes

Dot Grid

A grid of filled circles, radius mm each, spaced pitch mm apart on both axes and centered on the panel.

Diagonal Stripes

Parallel 45°-diagonal strokes spanning the full panel diagonal (width + height), so the field is always fully covered regardless of aspect ratio, spaced pitch mm apart.

Grid Lines

A plain rectilinear grid: vertical strokes every pitch mm, then horizontal strokes every pitch mm, both centered on the panel.

Concentric Circles

Rings expanding outward from a center point at (width/2, height × centerY), spaced pitch mm apart, out to the corner farthest from that center — so the rings always fully cover the panel even when centerY is off-center.

Hex Lattice

A honeycomb of pointy-top hexagon outlines, cell mm across, laid out on an offset-row lattice (w = √3 × r flat-to-flat column spacing, 1.5 × r row spacing, alternating rows offset by half of w).

Checker

A checkerboard of filled cell mm squares — the classic two-color grid pattern, drawn as filled squares only (the "off" squares are the panel's base color showing through).

Wave Lines

Horizontal sine-wave rows, pitch mm apart, each with amplitude mm of vertical swing and a wavelength mm period. The sine phase is anchored to the panel's horizontal center so the waves stay visually centered at any panel width.

Crosshatch

Two diagonal-stripe passes at right angles to each other (45° and 135°), both spaced pitch mm apart — Diagonal Stripes doubled and mirrored.

Radial Burst

count straight rays from a center point at (width/2, height × centerY), starting innerRadius mm out from the center (leaving a clear inner circle) and extending to the panel's far corner.

Brick

A running-bond brick course pattern: horizontal courses brickH mm tall, vertical joints every brickW mm, with alternating rows offset by half a brick width — the same offset convention real brickwork uses.

Diamond Lattice

An argyle-style field of diamond outlines (size mm point-to-point), laid out on two interleaved sublattices stepped by size/2 so adjacent diamonds share edges and tessellate seamlessly, instead of leaving gaps at the corners.

Scallops

Overlapping lower-semicircle arcs (width mm each), nested row to row like fish scales — each row offset horizontally by half a scallop width, and rows stacked one radius (half a scallop width) apart vertically.

Thumbnails

packages/patterns/src/thumbnail.ts renders the picker card preview shown in the pattern picker dialog. renderPatternThumb(canvas, gen, sizePx):

Sizes the canvas's backing store for the current devicePixelRatio while keeping its CSS box pinned to sizePx.
Scales the context so a fixed 30mm window (THUMB_SPAN_MM) fills the backing store exactly — every pattern's thumbnail frames the same physical span, so patterns with very different pitch/cell sizes stay visually comparable at a glance.
Fills the background black (#151515, mirroring the panel's soldermask base) and calls the generator's draw() with a fixed foreground (#d4af37, gold — mirroring exposed copper) and its own defaultParams().

The two thumbnail colors are literal constants local to thumbnail.ts, not imported from @zpd/core's PALETTE — a deliberate duplication so the @zpd/patterns package stays self-contained and dependency-free from @zpd/core.