diff --git a/docs/re/f6-unit2-parent-alpha-multiplies.md b/docs/re/f6-unit2-parent-alpha-multiplies.md index b139fc02..9dbcf2e8 100644 --- a/docs/re/f6-unit2-parent-alpha-multiplies.md +++ b/docs/re/f6-unit2-parent-alpha-multiplies.md @@ -1,4 +1,48 @@ -# F6 unit 2 β€” the parent's alpha **IS** multiplied into the sweep leaf +# F6 unit 2 β€” parent alpha multiplying in: 🟑 WEAKENED, not established + +> ## πŸ”΄ CORRECTION, same day β€” the identification was wrong, and so was my presentation +> +> The port challenged the by-size identification: both sweep sprites are the same +> size, so size cannot separate `pteff03` from `pteff03a`, and the two leaves have +> different alpha floors (128 and 0). **They were right that it was broken, and it +> is broken in a third way neither of us named.** +> +> Their proposed discriminator β€” the leaves travel in opposite directions β€” is in +> the capture, and it says: +> +> ``` +> 1.38x3.15 n=1140 x centre -1.690 -> +0.500 drift +2.190 LEFT->RIGHT +> 1.39x3.15 n= 614 x centre -1.685 -> +0.495 drift +2.180 LEFT->RIGHT +> ``` +> +> **Both rows travel the same way, so both are `pteff03`.** The 0.7 % size +> difference is per-frame rounding splitting ONE element across two keys β€” not two +> elements. `pteff03a` (declared right-to-left, 800 % scale, AABB β‰ˆ 3.62 NDC) does +> **not appear in this capture at all.** +> +> πŸ”΄ **And my own presentation misled.** The "alphas 8 24 33 50 58 …" I quoted were +> `sorted(set(...))[:9]` β€” the nine **lowest distinct** values, not the series. Read +> as a trajectory they look like a ramp from 8. They are a tail. The actual counts: +> +> ``` +> below 128: 9 of 1140 and 5 of 614 = 14 sub-floor samples out of 1754 +> ``` +> +> **So the bound argument survives in shape and collapses in weight.** Every sample +> below 128 is still unexplainable by a leaf that floors at 128 β€” but 14 of 1754 is +> a thin tail, and a tail is exactly where a vertex-grouping slip or a partial frame +> would show up. **Downgraded to 🟑: not refuted, not established.** +> +> **What would settle it:** the same capture read as a *series* rather than a set β€” +> alpha against frame across `t=70…100`, where a multiplying parent must produce a +> monotone ramp on nearly every frame, not 14 stragglers. That is one more read of +> data already on disk, and it is the next unit. +> +> The port was right to hold the renderer. Adopting this would have changed a +> rendering rule on every screen with a leaf, on 14 samples I had presented as a +> trajectory. + + **Status: βœ… measured ⟨capture⟩.** 2026-09-02.