25d73b4 said:
alpha testing (cutout) matters far more than alpha blending on this disc
and cited 0.98% fully clear against 1.08% partial as the evidence. Those two
numbers are the same size. The cutout path handles the fully-clear texels and the
blend path handles the partial ones, so the measurement I gave is if anything
marginally against the claim, not for it. The conclusion did not follow from the
number attached to it.
What survives is a different and weaker claim, and it is about failure shape
rather than texel count:
- a texel that should be discarded but is drawn puts geometry where there is
none. That is visible from a screenshot and someone will file a bug about it.
- a partial texel drawn opaque is a slightly wrong soft edge. That is not visible
and will not be reported.
So cutout first is still the right order, but the reason is which failure a human
notices, not how many texels are involved. Stated that way it is defensible;
stated the way I did it was an overclaim with a number attached to make it sound
measured, which is the specific failure mode rules 3 and 3a exist to prevent.
This is the fourth thing this session where a plausible implementation or claim
turned out to be wrong on inspection, and the second in two commits where the
error was in the reasoning rather than the code. Code errors get caught by tests
because the tests execute. Reasoning errors get caught by re-reading the number
the claim rests on and checking that it says what the sentence says.
Retracted and replaced rather than softened, per AGENTS 3a.
ReaperOfVeriod
87e2367daf