Fr0zka
8a303cc085
STAGE B group 5 of 5, and the only one that adds no operator. Stage B is complete: 19 ops, all
twelve detail modifiers ported.
THE DECISION, restated where it is paid for
The gate is a repeated early-out inside each operator (VF_NearCaveSurface), not a scoping
container. Reasons live in the code at that function; the short form is that the stack is a flat
list ClassifyBox folds op by op, a container would have to re-implement VF_FoldOp and would hide
its children from the fold, and an op that only exists inside a container cannot become a Phase-3
asset. What that choice buys in composability it pays for in risk: TWELVE places to forget the
gate instead of one. Hence a check aimed at exactly that.
NEW CHECK 1d
Classify each sample by its final SDF (nothing downstream of the room source writes that channel),
then compare the full stack against one with the eleven controllable amplitudes zeroed:
- outside the gate the two must be BIT-IDENTICAL -- asserted, and the leak count is printed;
- inside the gate they must differ often -- printed, and ZERO is an error, because "nothing
leaked" is worthless if the answer is "nothing happened anywhere". Same trap as a coverage
guard that only fires at zero, one level up: a check can be vacuous as well as a counter.
- the outside-gate sample count is printed and warns below 10%, since deep rock is the common
case in production and a sample set that never leaves the cave does not exercise the gate.
WHAT THIS CHECK CANNOT COVER, stated in the output rather than left implicit: the column operator
(STEP 4d) has no amplitude to zero, so it cannot appear in the zeroed stack. Its gate rides on
check 1's bit-identity against the original instead. That is sound but invisible, which is why the
info line says so.
Also corrected in the test header: the modifier count is TWELVE, not the thirteen that had been
carried in the notes, and only ELEVEN of them read the per-room param copy -- surface roughness
(4b) sits before the shadow declaration and reads strate params. Both numbers matter for C1.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>