HOW A SPECIMEN IS MADE.

The study is read

sharp decodes the committed PNG and resizes it to 900 units across. Every step below works in that pixel space, and it becomes the viewBox of the SVG.

The background is cut

A luminance mask keeps every pixel whose darkest channel sits below the ceiling: 244 of 255 by default, tightened per specimen in the manifest. On white paper with no cast shadow, that one comparison is the whole cut.

The mask is closed, then opened

Dilate, erode, erode, dilate, at a radius of one pixel. Closing first fills the pinholes a compressed study leaves behind; opening afterwards drops the speckle. In the other order the erosion takes a leg down to nothing before the dilation can put it back.

Small components are dropped

The mask is flood-filled into connected regions. The largest survives, along with every region holding at least four per cent of its area. A stray speck or the remains of a shadow leaves here.

The contour is walked

Every mask pixel with a background neighbour is a boundary pixel. Those are thinned to one point every few pixels and enter the point set first, so the silhouette is cut by real vertices. The mask border is also written into the edge field at full strength, which pulls further points onto the outline.

The interior is sampled

Points are drawn inside the mask's own bounding box, so the budget is spent where the specimen is. A Sobel edge field decides whether a candidate is kept: a flat region holds a floor of 0.035 and a turn raises that toward certainty. One point is allowed per blue-noise cell, and the cell is sized against the mask's area — cell = √(mask area / (points · 1.15)) — which keeps facets from clumping. The sampler is a mulberry32 generator seeded from the manifest, so the draw repeats exactly.

The points are triangulated

One Delaunay triangulation over the whole set, contour and interior together, through Delaunator.

Triangles outside the mask are dropped

A triangle whose centroid lands on background is discarded, and so is any triangle under a square unit of area. What survives covers the specimen and stops at its edge.

Each facet takes a colour

Four samples are averaged: the centroid, and three points half way from the centroid to each vertex. That average lands on the ink families named for the specimen — four of the nine logo inks on a market plate, all nine on the studio mark — where hue picks the family and brightness picks one of three steps of light: a shade mixed toward ink, the ink itself, and a tint mixed toward white. A facet carrying no hue lands on ink or on paper. The forge snaps at full strength, so every facet in a published mesh holds one of those flat values.

The facets are ranked along the spine

The covariance of the facet centroids gives the specimen's principal axis, and a facet's rank is its projection onto that axis, written into the polygon as --i. The fold then runs along the body, nose to tail on a quadruped and beak to feet on a wading bird, with no hand-authored axis to keep in step with the art.

The SVG is written

Coordinates round to whole units, because the viewBox is 900 across and a tenth of a unit is a fraction of a pixel. Each vertex is then pushed 0.45 units away from the centroid of its own facet, so neighbours overlap and no hairline of paper shows between them. Every polygon carries its rank and its fill and nothing more. A coarser second pass at 26 per cent of the budget merges same-colour facets into one path per ink, and that file is what the grid cells and the 64px marks load.