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Take the climb to a real branch point, and find the cadence has a third column

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FINDINGS 70, and it closes ROADMAP P6.  65.6 recorded that "the slack table is
here, but 51.3's refill climb with a second consumer through a real branch point
is not", and 67.6 repeated it verbatim two sessions later.
tools/analysis/36_branch_audio.py is that run: 51.3's surplus model, 56.3's 612
real branch points, 32's cadence arithmetic, both containers' headers and the
buffer constants of the player 68 measured, in one place.  No machine -- all
five were already numbers.

AUDIO IS 1.7% OF THE CODEC WIRE AND UP TO 3.30x OF THE CLIMB.  Slack accrues out
of pipe - wire, which is a small difference of two large numbers, so a second
consumer is not priced by its share of the wire -- which is how every budget in
this tree since FINDINGS 8 has quoted it.  At 451.4 KB/s (the container's own
zero-prefill pipe, 49.5) in a 256 KB ring the climb goes 6.70 s -> 22.11 s and
the branch points arriving under it go 482/612 (79%) -> 603/612 (99%).  At 488
it is 1.19x, at 600 it is 1.05x.  Correction to 56.4: it charged audio at
ratectl.AUDIO_KBPS = 7.8, which is 7,812.5 B/s in decimal kB; in binary KB the
figure is 7.6294, so the placeholder was 2.24% high and every column moved in
the flattering direction by less than one part in six hundred of the wire.

AND ON THE PACKED BRANCH THERE IS NO CLIMB AT ALL.  A record goes straight into
GVRAM, so the video lookahead is zero records and 56.4's alarming column is
vacuous when every frame arrives with less lookahead than the one before it.
Acceptance there is a per-frame deadline, not an average, which is why B1 has to
name a burst rate.  The only consumer on that branch with any lookahead is the
audio one: 1.833 s of sound held against 0.000 s of picture.  And at 589.6 KB/s
-- the acceptance figure this project quotes -- the sounded container's surplus
is exactly zero: it plays and never banks a byte, while the silent one climbs
its record in 6.38 s.

THE COST NOBODY HAD COUNTED.  A DLXP2 group is `lump k, then F records`, so lump
k is at a LOWER address than every record of its group but the first, and a seek
to record i finds its audio behind it.  Measured on the 409 within-container
seek targets of the arcade's own graph at the shipped F=11: mean 416.5 ms of
silence entering a branch, median 416.7, p90 750.0, worst 833.3, and only 36 of
409 land on a group boundary.  The other 203 -- the scene changes -- are free by
construction, because lump 0 sits between the header and record 0.  The
container's own start is the one branch point the cadence costs nothing at, and
it was the only one anybody had looked at.

SO THE CADENCE PICK IS REOPENED, on a third column.  32_audio_wire chose F=11 on
padding and RAM; F=1, the cadence it called the worst one, has no group to enter
off-boundary at all, and gives back 12,288 B of RAM for +4.36 KB/s of wire
(0.74% of the acceptance figure).  The alternative is a second read: lump k is
up to 503,808 B behind, so it is a separate command of 7,168 B -- 11.7 ms
against 416, 36x cheaper in time -- and src/player/packed.s starts PG_AK/PG_AKF
at lump 0 and has no audio seek path at all.  Nothing here decides it; the
deciding number is what one more SCSI command costs, and that is B1's.  The
content is not uniform mod F either: the measured mean runs 0.67x..1.23x of a
uniform assumption across the sweep, and the 1.00x at F=11 is a coincidence.

New check.sh stage, ~10 s, and it gates the STRUCTURE and deliberately not the
milliseconds: audio never shortens a climb, the shipped cadence strands most
within-container branches, F=1 strands none, and the lump read is an order of
magnitude cheaper than the silence it removes.

The one thing 70.3 and 70.4 rest on is a DESIGN ASSUMPTION and is printed in the
tool's own output: one container per SCENE (53, 55.1, 56.3).  One container per
sequence makes every seek land on frame 0 and empties both sections.

No encoder, player or container byte moved.

Claude-Session: https://claude.ai/code/session_01194oWYW8DQXK1SZ2DnChW6
This commit is contained in:
prosolis
2026-08-25 14:21:32 -07:00
parent ab15c0749a
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#!/usr/bin/env python3
"""51.3's REFILL CLIMB WITH A SECOND CONSUMER, THROUGH A REAL BRANCH POINT.
python3 tools/analysis/36_branch_audio.py --kbps R [R ...]
[--ring KB ...] [--gate]
The oldest open item in ROADMAP P6, named by FINDINGS 65.6 and again by 67.6:
"the slack table is here, but 51.3's refill climb with a second consumer
through a real branch point is not."
Everything it needs already exists and none of it has ever been put in the same
room:
* 51.3 -- slack is ACCUMULATED out of `pipe - wire`, at `pipe - wire` bytes a
second, and a seek spends all of it. `tools/analysis/20_seek_slack.py`.
* 56.3 -- where the branch points ARE: 612 distinct transitions into a seek
over the arcade's own graph, worst gap 0.000 s, median 3.473 s.
`tools/analysis/25_scene_graph.py`, reading only DLXSCENE1.
* 56.4 -- the climb against that distribution, for the codec container. It
charged audio as `ratectl.AUDIO_KBPS`, a flat 7.8 KB/s placeholder that
predates any of the audio work.
* 65.3/67.1 -- what a second consumer ACTUALLY costs a container: a fixed
cadence of F frames per A sectors, because a packed record's address is
arithmetic and cannot be an index. `tools/analysis/32_audio_wire.py`.
* 68 -- the player that holds both streams at once, and its buffers.
Three questions, and the tree has never asked any of them:
1. What does the SECOND CONSUMER do to the climb? Not to the wire -- 32
answered that and it is 1.3% -- but to `pipe - wire`, which is a small
difference of two large numbers and is the thing the climb is made of.
2. What is the climb on the PACKED branch? This is the branch the player
runs (68) and the one B1's acceptance is written against.
3. What does the CADENCE do at a branch point? A group is `lump k, then F
records`, so lump k sits at a LOWER address than every record in its group
but the first. A seek to record i lands inside a group whose audio is
BEHIND it. Nobody has ever priced entering a group off-boundary, and the
game's own seek targets say how often it happens.
THE FRAME INDEX OF A SEEK TARGET IS A DESIGN ASSUMPTION AND IS LABELLED ONE.
DLXSCENE1 carries positions on the laserdisc timeline in ms. This tree's design
puts ONE CONTAINER PER SCENE -- 53 and 55.1 charge a scene change 6,164 header
bytes, and 56.3 counts 203 of the 612 transitions as container changes for
exactly that reason -- so a seek target's frame index inside its container is
`(target start - the scene's own earliest start) * fps / 1000`. If the design
ever puts one container per SEQUENCE instead, every seek lands on frame 0, the
group offset is always zero and section 3 collapses to nothing. That is the
assumption, said out loud, in the one place the answer depends on it.
"""
import sys, os, json, argparse, importlib.util
sys.path.insert(0, "tools/encoder")
sys.path.insert(0, "tools/analysis")
TABLE = os.environ.get("DLX_SCENEGRAPH", "tmp/scenegraph.json")
FPS = 12
CHIP_HZ = 15625.0 # MSM6258V, 8 MHz / 512 (FINDINGS 32, 65)
AU_BPS = CHIP_HZ / 2 # 4 bits a sample, two samples to a byte
AU_FRAME = AU_BPS / FPS # 651.0416... B a slot, and the dots are 65.3
SECTOR = 512
def load(path, name):
spec = importlib.util.spec_from_file_location(name, path)
m = importlib.util.module_from_spec(spec)
spec.loader.exec_module(m)
return m
def cadence(F):
"""Best A for this F: the fewest whole sectors that hold F frames of chip."""
num, den = int(round(AU_BPS * 2)), 2 * SECTOR * FPS
A = -(-(num * F) // den) # ceil(F * bytes/sector)
return A, A * SECTOR
def climb_s(records, rec_b, pipe_kbps, wire_kbps):
"""Seconds of play to accumulate `records` records of lookahead (51.3)."""
surplus = (pipe_kbps - wire_kbps) * 1024.0
return float("inf") if surplus <= 0 else records * rec_b / surplus
# --------------------------------------------------------------- the branches
def branch_points(doc, nodes, sg):
"""The 612 transitions into a seek, plus each one's target frame index.
Returns (gaps_s, within, changes). `within` entries carry the frame index
the seek lands on inside its container; `changes` are scene changes, which
land on frame 0 of a new one.
"""
gaps, _ = sg.worst_gap(nodes)
play = [g for g in gaps if g[5] != "attract_mode"]
scene_start = {}
for scene, seqs in doc["scenes"].items():
st = [s["start_ms"] for s in seqs.values() if s["start_ms"] >= 0]
scene_start[scene] = min(st) if st else None
within, changes = [], []
for g, src, tgt, kind, ends, scene in play:
if ends:
changes.append((g / 1000.0, src))
continue
n = nodes.get(f"{scene}.{tgt}")
if n is None or not n.seeks or scene_start[scene] is None:
continue
i = int(round((n.start - scene_start[scene]) / 1000.0 * FPS))
within.append((g / 1000.0, max(0, i), f"{scene}.{tgt}"))
return sorted(g[0] / 1000.0 for g in play), within, changes
def silences(within, F):
"""Ms of silence entering each branch's group off-boundary, at cadence F.
A group is `lump k, then F records`. Seek to record i, take the next lump
that lies AHEAD of the read point -- lump k+1, which arrives at frame
(k+1)*F -- and the frames from i to (k+1)*F-1 have no audio. The chip's
second is a real second (15,625 samples, 2 to a byte), so the missing
time is exactly `(F - i mod F) mod F` frames of 1/12 s and none of
FINDINGS 54's frame-clock remainder gets into it.
"""
return sorted(((F - (i % F)) % F) / FPS * 1000.0 for _, i, _ in within)
def pct(xs, p):
return xs[min(len(xs) - 1, int(p * len(xs)))] if xs else float("nan")
def main():
ap = argparse.ArgumentParser()
ap.add_argument("--kbps", type=float, nargs="+",
help="delivered pipe rates, KB/s. REQUIRED (FINDINGS 50) "
"unless --gate, which carries its own.")
ap.add_argument("--ring", type=float, nargs="+", default=[256, 512])
ap.add_argument("--pkbps", type=float, nargs="+",
default=[589.6, 600.0, 650.0, 700.0, 900.0],
help="pipe rates for the PACKED table. Its own list, "
"because a packed record is 1.3x the codec's and "
"every rate that serves one starves the other.")
ap.add_argument("--table", default=TABLE)
ap.add_argument("--packed", default="tmp/packed_singe.dlxp")
ap.add_argument("--codec", default="tmp/rc_fr_singe_scsi_span.dlx")
ap.add_argument("--fsweep", type=int, default=12,
help="highest cadence F in the pick table")
ap.add_argument("--gate", action="store_true",
help="check.sh mode: fixed rates, and assert the structural "
"results rather than print the essay")
a = ap.parse_args()
if a.gate and not a.kbps:
a.kbps = [451.4, 488.0, 600.0]
if not a.kbps:
ap.error("--kbps is required and has no default (FINDINGS 50)")
if not os.path.exists(a.table):
print(f"no scene table at {a.table} -- run:\n"
f" python3 tools/import/scenegraph.py")
return 2
doc = json.load(open(a.table))
if doc.get("format") != "DLXSCENE1":
print(f"{a.table}: not a DLXSCENE1 table")
return 2
sg = load("tools/analysis/25_scene_graph.py", "scene_graph")
ss = load("tools/analysis/20_seek_slack.py", "seek_slack")
from dlxp import DLXP
import ratectl as RC
nodes = sg.build_graph(doc["scenes"])
gaps, within, changes = branch_points(doc, nodes, sg)
med = gaps[len(gaps) // 2]
d = DLXP(a.packed)
P_REC = d.rec_bytes
P_VID = P_REC * FPS / 1024
F0, A0 = d.cad_f, d.cad_a
P_AUD = A0 * SECTOR / F0 * FPS / 1024
print(f"""
=== WHAT EACH BRANCH ACTUALLY HOLDS ====================================
51.3's climb is a statement about an ACCUMULATOR. The two branches of this
project do not have the same one, and one of them does not have one at all.
codec ({os.path.basename(a.codec)})
a {a.ring[0]:.0f} KB ring of variable records with an index in front of it;
lookahead is whole records and the ceiling is what 20_seek_slack.py
simulates.
packed ({os.path.basename(a.packed)})
a record is {P_REC:,} B of literal picture and the channel puts it
STRAIGHT INTO GVRAM (FINDINGS 61, 62, 64). There is no record
buffer, so the VIDEO lookahead is ZERO records and there is nothing
to climb. The only consumer on that branch with any lookahead at
all is the AUDIO one: {d.cad_a * SECTOR:,} B a lump, PG_ANBUF={3} slots and
PG_APRE prefilled at {2} for the run 68 measured (it is a mailbox,
not a constant: src/player/packed.s, 68.6).
That is {2 * F0 / FPS:.3f} s of sound held against {0.0:.3f} s of picture.
The CPU-painted packed variant (64.2's column B) is the one that holds two
record buffers and 99,328 B, and it is the only packed configuration the
word "climb" applies to. Both are priced below.
=== THE BRANCH POINTS, OUT OF THE ARCADE'S OWN GRAPH ====================
{len(gaps)} transitions into a seek (attract mode excluded, 56.3)
worst {gaps[0]:.3f} s p10 {pct(gaps,.10):.3f} median {med:.3f} p90 {pct(gaps,.90):.3f}
{len(changes)} of them END THE SCENE and are container changes;
{len(within)} land INSIDE a container, at frame indices 0..{max(i for _, i, _ in within)}""")
# ---------------------------------------------------------------- 1
dc, rec = ss.records(a.codec)
C_REC = float(rec.mean())
C_VID = C_REC * FPS / 1024
print(f"""
=== 1. THE CLIMB WITH THE SECOND CONSUMER (the codec branch) ============
Audio is {AU_BPS/1024:.3f} KB/s and this container pays no padding for it (65.4: it
already has an index and already has variable records). Against a video wire
of {C_VID:.1f} KB/s that is {100*(AU_BPS/1024)/C_VID:+.2f}% -- and the climb is not built out of the wire,
it is built out of `pipe - wire`, so that is not the number that matters.
{'ring':>5} {'pipe':>7} {'ceil':>5} {'climb SILENT':>13} {'SOUNDED':>9} {'x':>6}"""
f" {'under, silent':>13} {'under, sounded':>14}")
tab1 = []
for ring_kb in a.ring:
ring = int(ring_kb * 1024)
for kbps in a.kbps:
fill = (kbps - AU_BPS / 1024) * 1024 / FPS
lo, hi, ring_ref, rate_ref = ss.paced_sim(rec, ring, fill)
ceil = int(hi.max())
cs = climb_s(ceil, C_REC, kbps, C_VID)
ca = climb_s(ceil, C_REC, kbps, C_VID + AU_BPS / 1024)
us = sum(1 for g in gaps if g < cs)
ua = sum(1 for g in gaps if g < ca)
ratio = ca / cs if cs not in (0.0, float("inf")) else float("inf")
tab1.append((ring_kb, kbps, ceil, cs, ca, ratio, us, ua))
print(f" {ring_kb:5.0f} {kbps:7.1f} {ceil:5d} {cs:12.2f}s "
f"{ca:8.2f}s {ratio:5.2f}x {f'{us}/{len(gaps)}':>13} "
f"{f'{ua}/{len(gaps)}':>14}")
worst = max(tab1, key=lambda r: r[5])
print(f"""
THE SECOND CONSUMER IS {100*(AU_BPS/1024)/C_VID:.1f}% OF THE WIRE AND UP TO {worst[5]:.2f}x OF THE CLIMB.
At {worst[1]:.1f} KB/s in a {worst[0]:.0f} KB ring the climb goes {worst[3]:.2f} s -> {worst[4]:.2f} s and the
branch points that arrive under it go {worst[6]}/{len(gaps)} -> {worst[7]}/{len(gaps)}
({100*worst[6]/len(gaps):.0f}% -> {100*worst[7]/len(gaps):.0f}%). Nothing about audio got bigger; the
DIFFERENCE it is subtracted from got smaller, and the climb is made of the
difference. This is why 51.4's rate/ring distinction matters more with a
second consumer than without one, and why quoting audio as a share of the
wire (32, and every budget before it) understates it at every rate close to
the wire.
A CORRECTION TO 56.4, and it is small: that table charged audio at
ratectl.AUDIO_KBPS = {RC.AUDIO_KBPS} KB/s, which is {AU_BPS:.1f} B/s expressed in decimal
kB (21_iplrom_dmac.py says so). In binary KB the figure is {AU_BPS/1024:.4f}, i.e.
{100*(RC.AUDIO_KBPS-AU_BPS/1024)/(AU_BPS/1024):+.2f}%. Every column of 56.4 moves in the flattering direction by
less than one part in six hundred of the wire. It is recorded because a
placeholder that turns out to be right is still a placeholder.""")
# ---------------------------------------------------------------- 2
print(f"""
=== 2. THE PACKED BRANCH: THERE IS NO CLIMB, AND THAT IS THE FINDING ====
video {P_VID:.1f} + audio {P_AUD:.4f} (F={F0}, A={A0}, {A0*SECTOR:,} B a lump) = {P_VID+P_AUD:.1f} KB/s,
which is B1's acceptance figure and is where it comes from.
DMAC-direct (what src/player/packed.s runs, FINDINGS 64/68):
video lookahead 0 records. The climb does not exist, the ceiling does not
exist, and the {len(gaps)} gaps buy it NOTHING -- there is no accumulator for
play to fill. Its acceptance is a PER-FRAME deadline: {P_REC:,} B must land
inside every slot, and a rate that averages {P_VID+P_AUD:.1f} KB/s over a second is
not the same claim. 56.4's alarming column -- most branch points arrive
with less lookahead than the one before them -- does not apply to it,
because every frame arrives with less lookahead than the one before it.
CPU-painted (64.2 column B, 99,328 B, two record buffers -> 1 record of
lookahead):
{'pipe':>7} {'climb SILENT':>13} {'SOUNDED':>9} {'x':>6} {'under, silent':>13} {'under, sounded':>14}""")
tab2 = []
def secs(x, w):
return f"{x:{w}.2f}s" if x != float("inf") else f"{'never':>{w+1}}"
for kbps in a.pkbps:
cs = climb_s(1, P_REC, kbps, P_VID)
ca = climb_s(1, P_REC, kbps, P_VID + P_AUD)
us = sum(1 for g in gaps if g < cs)
ua = sum(1 for g in gaps if g < ca)
r = ca / cs if cs not in (0.0, float("inf")) else float("inf")
tab2.append((kbps, cs, ca, r, us, ua))
print(f" {kbps:7.1f} {secs(cs,12)} {secs(ca,8)} "
f"{(f'{r:5.2f}x' if r != float('inf') else ' inf ')} "
f"{f'{us}/{len(gaps)}':>13} {f'{ua}/{len(gaps)}':>14}")
print(f" -- and EVERY rate in section 1's table is below {P_VID:.1f} KB/s, so "
f"none of\n them serves this container at all.")
print(f"""
READ THE FIRST ROW. At {P_VID+P_AUD:.1f} KB/s -- the acceptance figure this project
quotes -- the SILENT container still climbs its one record in {tab2[0][1]:.2f} s and
the SOUNDED one NEVER DOES, because {P_VID+P_AUD:.1f} is where its surplus is exactly
zero. The acceptance figure is the rate at which the sounded container has
no lookahead at any amount of play, which is a different thing from the rate
at which it plays.
A packed record is 1.3x the codec's mean record and the packed wire is 1.3x
the codec's, so a rate that is generous to one is tight for the other and the
same audio debit costs the packed climb more. ONE RECORD of lookahead is
1/12 s of tolerance and it takes seconds of play to earn.
THE TWO BRANCHES DIFFER HERE ON A COLUMN THAT IS NOT CLOCKS, which is the
third time (61.9, 64.2, and this). The packed branch spent its ring to
delete a decoder; what it bought with the RAM is a player with no tolerance
for a slow record at ANY time, not merely after a branch.""")
# ---------------------------------------------------------------- 3
sil = silences(within, F0)
free = sum(1 for x in sil if x == 0.0)
P_PIPE = a.pkbps[1] if len(a.pkbps) > 1 else a.pkbps[0]
lump_ms = A0 * SECTOR / (P_PIPE * 1024) * 1000
behind = (F0 - 1) * P_REC + A0 * SECTOR
print(f"""
=== 3. THE COST NOBODY HAD COUNTED: entering a group off-boundary =======
A DLXP2 group is `lump k, then F records` (dlxp.py), so lump k is at a LOWER
address than every record of its group except the first. Reading forward from
record i, the next lump to arrive is k+1, and it carries frame (k+1)*F. The
frames from i to (k+1)*F-1 therefore have picture and no sound.
Measured on the {len(within)} within-container seek targets of the arcade's own
graph, at the shipped cadence F={F0}:
mean {sum(sil)/len(sil):7.1f} ms of silence entering the branch
median {pct(sil,.50):7.1f} p90 {pct(sil,.90):7.1f} worst {sil[-1]:7.1f}
free {free}/{len(within)} land on a group boundary and cost nothing
The other {len(changes)} branch points -- the scene changes -- are FREE, and by
construction: lump 0 sits at sector 1 and record 0 at {d.off_frm:,}, so a
container's own first bytes are header, lump, record and a scene change reads
them in one forward pass. **The container's start is the one branch point
the cadence costs nothing at, and it is the only one anybody had looked at.**
THE FIX IS A SECOND READ AND NOBODY HAS ONE. Lump k is {behind:,} B behind
record i at worst, so it cannot be picked up by reading early -- it is a
separate command at a separate LBA, of {A0*SECTOR:,} B, which at {P_PIPE:.1f} KB/s is
{lump_ms:.1f} ms against a mean {sum(sil)/len(sil):.0f} ms of silence -- {sum(sil)/len(sil)/lump_ms:.0f}x cheaper in TIME,
one more command per branch, and the command overhead is B1's and unmeasured.
src/player/packed.s starts PG_AK and PG_AKF at lump 0 and has no audio seek
path at all; the player that branches needs one.
=== 4. THE CADENCE PICK, WITH THE THIRD COLUMN IT DID NOT HAVE ==========
32_audio_wire.py chose F={F0} on two columns, padding and RAM. Here is the same
sweep with the branch column, measured on the game's own seek targets rather
than assumed uniform:
{'F':>3} {'A':>3} {'lump B':>8} {'pad%':>7} {'aud KB/s':>9} {'RAM x2':>8} {'mean sil':>9} {'p90':>8} {'worst':>8} {'free':>10} {'vs uniform':>11}""")
for F in range(1, a.fsweep + 1):
A, lump = cadence(F)
need = F * AU_FRAME
s = silences(within, F)
uni = (F - 1) / 2 / FPS * 1000.0
mean = sum(s) / len(s)
mark = " <- shipped" if F == F0 else ""
print(f" {F:3d} {A:3d} {lump:8,} {100*(lump-need)/need:6.2f}% "
f"{lump/F*FPS/1024:8.3f} {2*lump:8,} {mean:8.1f} "
f"{pct(s,.90):8.1f} {s[-1]:8.1f} "
f"{f'{sum(1 for x in s if x == 0)}/{len(s)}':>10} "
f"{(mean/uni if uni else 1.0):10.2f}x{mark}")
ratios = []
for F in range(2, a.fsweep + 1):
sF_ = silences(within, F)
ratios.append((sum(sF_) / len(sF_)) / ((F - 1) / 2 / FPS * 1000.0))
min_r, max_r = min(ratios), max(ratios)
A1, l1 = cadence(1)
AF, lF = cadence(F0)
s1, sF = silences(within, 1), silences(within, F0)
print(f"""
F=1 -- "one lump a record", the cadence 32 called THE WORST ONE -- has no
group to enter off-boundary, no second read, no audio seek path and 2,048 B
of held lump instead of {2*lF:,}. It costs {l1/1*FPS/1024 - lF/F0*FPS/1024:+.3f} KB/s of wire, which is
{100*(l1/1*FPS/1024 - lF/F0*FPS/1024)/(P_VID+P_AUD):+.2f}% of the packed acceptance figure, and it BUYS BACK {2*lF-2*l1:,} B
of RAM on the branch whose whole argument is that RAM is what it has spare.
THE PICK IS THEREFORE REOPENED, and it is a real trade rather than an error:
padding is what F={F0} minimises and padding is not the only thing F sets.
A player that gets its audio seek right is indifferent; a player that does
not pays a mean {sum(sF)/len(sF):.0f} ms of silence at {len(within)} of the game's {len(gaps)} branch
points. Nothing here decides it -- the deciding number is the SCSI command
overhead of the extra read, and that is B1's.
AND THE CONTENT IS NOT UNIFORM MOD F. A uniform assumption would put the
mean at (F-1)/2 frames; the arcade's seek targets land where they land, and
the ratio column above runs {min_r:.2f}x..{max_r:.2f}x over the sweep, so a design
that assumed uniform would be out by a quarter at F=3. At the shipped F={F0} it is
{(sum(sF)/len(sF))/((F0-1)/2/FPS*1000):.2f}x, which is a coincidence and is reported as one.
=== 5. WHAT THIS DOES NOT ESTABLISH ====================================
1. NO RATE HERE IS MEASURED. Every pipe column is a sensitivity (FINDINGS
50), and B1 -- sustained AND data-phase burst -- is still the user's.
2. THE FRAME INDEX OF A SEEK TARGET IS A DESIGN ASSUMPTION. One container
per SCENE (53, 55.1, 56.3). One container per SEQUENCE makes section 3
zero and section 4 moot; nothing else in the file changes.
3. NOTHING RAN ON THE MACHINE. This is arithmetic over a scene table, two
containers and a player's own constants. 68's player has never seeked.
4. THE MECHANICAL SEEK IS STILL UNMODELLED (51.7.5) and is charged on top of
every millisecond here.
5. THE SILENCE IS A CONTAINER PROPERTY, NOT A CHIP ONE. What the MSM6258
does when it is not fed -- hold the last sample, or click -- is a board
question and belongs with session 34's fifth hardware item.""")
if a.gate:
# Structural assertions. Not the milliseconds -- those move with the
# scene table -- but the ORDER and the SIGNS, which are the finding.
ok = True
def check(cond, msg):
nonlocal ok
print(f" {'OK ' if cond else 'FAIL'} {msg}")
ok = ok and bool(cond)
print("\n=== GATE ===============================================")
check(len(gaps) == 612, f"612 transitions into a seek, got {len(gaps)}")
check(len(within) + len(changes) == len(gaps),
f"{len(within)} within + {len(changes)} scene changes = {len(gaps)}")
check(all(r[5] >= 1.0 for r in tab1),
"audio never SHORTENS the codec climb")
check(max(r[5] for r in tab1) > 1.5,
f"and at some rate it more than 1.5x's it "
f"({max(r[5] for r in tab1):.2f}x)")
check(all(r[7] >= r[6] for r in tab1),
"and never lowers the count of branch points under the climb")
check(free < len(within) // 2,
f"most within-container branches enter a group off-boundary "
f"({len(within)-free}/{len(within)})")
check(silences(within, 1) == [0.0] * len(within),
"F=1 has no off-boundary case at all")
check(sum(sil) / len(sil) > 10 * lump_ms,
f"the silence F={F0} costs is >10x the lump read that removes it "
f"({sum(sil)/len(sil):.0f} ms vs {lump_ms:.1f} ms)")
print(" " + ("BRANCH-AUDIO GATE GREEN" if ok else "BRANCH-AUDIO GATE RED"))
return 0 if ok else 1
return 0
if __name__ == "__main__":
sys.exit(main())
tools/bench/check.sh
+23
View File
@@ -846,4 +846,27 @@ python3 tools/analysis/35_audio_level.py --gate > tmp/audio_level.log 2>&1 \
grep -aE "DISC PEAK|LOUDEST PASSAGE|THE CLAMP|LEVEL GATE|NO AUDIO TRACK|^ 1\.0000|^ 0\.5" \
tmp/audio_level.log
echo "--- session 38: the refill climb with a second consumer, through a real branch point (FINDINGS 70) ---"
# ROADMAP P6, the oldest item in it: 65.6 and 67.6 both recorded that the slack
# table existed and that 51.3's climb had never met a branch point with audio on
# the wire. This is that run. It needs the scene graph, so it skips with the
# session-24 stage when there is no checkout.
#
# WHAT IS GATED IS STRUCTURAL, and deliberately not the milliseconds: the
# silences move with the scene table and with the one-container-per-scene
# assumption the tool prints in its own section 5. What must not move is the
# ORDER and the SIGNS -- audio never shortens a climb, the shipped cadence
# strands most within-container branch points off a group boundary, F=1 strands
# none, and the lump read that removes the silence is an order of magnitude
# cheaper than the silence. A tree where any of those flipped has a different
# answer to the cadence pick.
if [ -f "$DIRKSIMPLE/data/games/lair/game.lua" ]; then
python3 tools/analysis/36_branch_audio.py --gate \
> tmp/branch_audio.log 2>&1 || { cat tmp/branch_audio.log; exit 1; }
grep -aE "^ (OK|FAIL) |SECOND CONSUMER IS|BRANCH-AUDIO GATE|^ mean |^ free " \
tmp/branch_audio.log
else
echo " SKIPPED: no DirkSimple checkout at $DIRKSIMPLE"
fi
echo "ALL GREEN"