re: the pivot mismatch cannot be the swoosh's cause -- refuting my own

candidate with the check I named

Last iteration I offered the pivot mismatch as a quantified candidate for
the swoosh rendering too thick, and said explicitly that whether it bites
depends on which pivot the compositor uses and that I had not checked. I
checked.

blit takes the drawn size from the TEXTURE and uses the pivot only as the
scale anchor, kf.x minus pivot times scale-minus-100 over 100. At scale
100 that term is zero. And every one of the seven swoosh elements --
ptlogo_back2, its glow and the five eff segments -- reports a single
scale of (100,100) across all its keyframes. So the mismatch, real as it
is in the data, cannot move or resize the swoosh in our render. Refuted,
under my own name.

It is not harmless everywhere, and I have said where it does bite:
ptlogo1 and ptlogo2 run 100, 101, 103, 112, 150 during the build-in, so
there the wrong pivot really does displace them -- during the animation
rather than at rest.

What that leaves is the blend, by elimination rather than by evidence.
Position and size are the texture's own and right, fade is
white-with-alpha, tint is white, the texture is blue-leaning rather than
pink. Seven overlapping sprites at 5 to 23 percent opacity stacked with
plain alpha-over saturate toward opaque white, which is what we draw and
would read as thicker beside the game's thin coloured stroke. Recorded as
the remaining candidate and explicitly not as a diagnosis -- no blend
mode has been identified in the data.
This commit is contained in:
Sylpheed RE agent
2026-08-28 21:40:46 +00:00
parent 2a0afc1405
commit c10802536f
3 changed files with 52 additions and 15 deletions

View File

@@ -35,6 +35,13 @@ neighbourhood, not just the line.
## Screens, classes and RTTI
* "the title logo elements' wrong pivots (off by up to 59 px, authored against the
other language's sprite) explain the swoosh rendering too thick" → **mine, and
refuted.** `blit` sizes from the texture and applies the pivot only as
`pivot·(scale100)/100`; all seven swoosh elements are scale `(100,100)` at every
keyframe, so the term is zero. The mismatch is real but inert here — it would
bite `ptlogo1`/`ptlogo2`, which scale to 150 during the build-in.
[`ui-title-build-map.md`](ui-title-build-map.md)
* "the title screen loops at ≈ 2.2 s" → **mine, and doubly wrong.** The title
*art* is near-static (wordmark sd 0.06); the 2.3 s pulse is the
**`PRESS Ⓐ BUTTON` plate**, which is a *different build* (2, not 4). Localised