SpriteTextureOptions

The same name and the same two values SurfaceTexture already takes, so a consumer that has uploaded a texture to the mesh path does not meet a second vocabulary here.

A sprite sheet is usually pixel art, where linear filtering is the thing that makes it look wrong; and a sheet that is not pixel art is normally drawn near its authored size, where the two filters differ by very little. So the default costs the smooth case almost nothing and saves the sharp case from a blur nobody asked for.

The case it exists for is type baked into an atlas. The comment on filter says a sheet that is not pixel art "is normally drawn near its authored size, where the two filters differ by very little" — a glyph page is the sheet where that is not true. A consumer baking one page per weight at 96 px and drawing body copy at 11 is minifying 7x, and linear reads four texels of a footprint that covers dozens: a t crossbar two texels tall lands on about a quarter of a pixel, and whether it survives depends on where the sample falls. Reported by a player as Step-In Uppercut reading Slep-In Uppercul, with different strokes lost per glyph and per position, so the line looks unevenly spaced as well as misread.

Neither workaround available to a consumer is good: baking nearer the drawn size blurs the headings, because one atlas cannot serve an 8x range of sizes, and baking a second atlas for small text doubles the pages and the uploads and moves a sampling decision into the game where it has to be re-tuned whenever a size changes.

Off by default because the chain is wrong for pixel art, which is what most sheets are: it is memory nothing samples, and at a distance it dissolves art whose whole point is the pixel.

With filter: 'linear' this is trilinear — blended within a level and between levels. With filter: 'nearest' the levels are still blended, because that is minification and filter is about magnification; SurfaceTexture makes the same split and for the same reason.

Padding cells against bleed is the caller's problem, and it has to be: a lower level mixes texels the atlas packer put next to each other, so a sheet whose frames touch will show its neighbours. How much padding depends on how far the chain is allowed to go, which is a fact about the sheet rather than about the sampler.