An exact box-filtered lattice ink: shapes that are constant on unit cells (a QR code is the canonical one), rendered with the Slug text renderer's philosophy -- recompute exact analytic coverage at the pixel's true derivative footprint, every frame -- but with the outline integral replaced by a lattice integral.

The compositing rule is the whole point. Drawing a module grid as many rectangles gives every shared edge two half-coverage fragments that OVER-composite to three quarters of either ink: a light hairline on every module boundary, which shimmers as the surface moves. Here the entire grid is one primitive whose fragment computes one coverage value for the whole footprint, so there is no interior boundary to leak.

The closed form is a summed-area table. The SAT of a function constant on unit cells is exactly bilinear within each cell, so the continuous integral over [0,x]*[0,y] is four integer texel loads and two lerps -- not approximately, exactly. A box filter needs that integral at its four corners; sixteen loads make the coverage exact at every scale, magnified or minified, one code path, no mip chain. Where Slug pays a fold over a band's curve list per fragment, the lattice pays O(1).

The filter footprint and width come from the same derivatives and the same knobs as slug-pixels-per-em, so a code and the text beside it on one panel are filtered identically.

Vertex lanes arrive through the analytic family's own vertex stage: the local coordinate carries cell units, the half-size lanes carry the grid's column and row counts, and the color is the premultiplied ink of the INKED cells. The zero cells are white paper, and the paper's own outer edge is part of the same integral: alpha is the footprint's overlap with the grid rectangle, so even the card boundary is filtered, and no part of the drawing is composited against another part of itself.