A gallery of custom-material effects: dissolve, hologram, posterize, ghost fade, hit flash and hue cycle, plus wave and chromatic distortion, which call sampleTexture(uv) to read the texture again at shifted coordinates.
Each is a single fn effect(color, uv) passed to createMaterial, and all animate purely from the automatically injected mu.time: no useUpdate, no per-frame wiring. An effect is a function; reusing it is reusing the string.