The port isolated main_menu's 10.88 -> 13.02 regression to pteff10 and
asked whether the per-draw log shows it alpha-over, which would be a
counter-example to ui-blend-mode-decoded.md.
It does not. blend-bit-vs-oracle.txt has pteff10 ADDITIVE on entry 5 (main
menu) AND entry 6 (extras), both labels read out of the guest command
stream, and HANDOFF states it from three independent menu sessions, every
frame.
The premise came from a stale coverage table of mine that the same HANDOFF
entry had already corrected in place. Recording that: a correction which
leaves the wrong table visible upstream of it has not landed.
And the regression was predicted on this exact element before adoption --
HANDOFF flagged pteff10 as the one row the port's renderer would not
corroborate, because for a dim wholly-semi-transparent glow (max alpha 130)
over a dark background additive and alpha-over nearly coincide. A renderer
metric getting worse while the render gets more correct is the standing
rule with a number on it.
Separately, the port answered my finding-3 candidate: a frozen sweep of the
plate region rises monotonically across the declared 214->236, so the port
fades rather than pops and its t=236 is a completion. That kills the onset
branch.
Two of the play-test's four named candidates for finding 3 are now dead --
units/s (measured at 60) and the ramp. Finding 3 has no surviving named
cause. The clock origin is the one to take next, because every measurement
so far is a DIFFERENCE between two events and a difference cannot detect a
common offset.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01Jc4pciRArGHfxGGhEbwp5t
Answered against the pre-registration committed before the capture.
Units per second was the last open number on the PRESS (A) plate, and both
prior measurements of it were wall-clock readings off an emulator that runs
the guest slow by an unknown factor. They disagreed by 2.9x, because a 30 Hz
guest at full speed and a 60 Hz guest at half speed look identical on a wall
clock.
The ruler here is not a clock. ADV.wmv declares 30.0000 fps in its own ASF
header, so a decoded movie frame is a tick the emulator's speed cannot
stretch. Presented frames per decoded movie frame is guest_fps/30 with no
wall clock in the chain.
predicted H_A 30 fps -> 60 units/s -> 1.0
H_B 60 fps -> 120 units/s -> 2.0
measured 1.0000
Both pre-registered guards pass. Guard 2: a perfect repeating 3-buffer
cycle, 52 uses each (exactly 156/3), 2 chroma planes per luma on 156 of 156.
Guard 1: run lengths are 156 runs ALL of length 1 -- no smear, so the
dropped-movie-frame bias that would have pushed the answer toward 120 is
measurably absent rather than argued away.
So H_A. The port keeps its 60 and changes nothing.
REFUTES the live H3 hypothesis that 120 units/s explains the play-test's
late plate. That hypothesis was well-formed and attractive precisely because
it would have explained the complaint, which is why it needed a ruler that
is not a clock.
Which means finding 3 still has no cause. The strongest remaining candidate
is decoded rather than speculative: the plate's declared onset is t=214, not
t=236 -- a 22-unit fade, matching the T=22 the oracle confirmed by measuring
+23 alpha per presented frame on that element.
The pre-registered control could NOT be run: this logger build emits vb=
addresses, not vertex contents, so there was no alpha to check +34 against.
A weaker control is substituted and labelled -- the splash shader/blend
census, which validates the log's structure (what this measurement uses) and
not alpha extraction (which it does not).
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01Jc4pciRArGHfxGGhEbwp5t
