* fix(render): glyph surgery so Spleen 5x8 K no longer reads as H
The stock Spleen K was H with one crossbar pixel removed (Hamming 1), the
worst confusable pair in the atlas. Because the API downscales images and the
model infers rather than scans, that difference vanishes and K is silently
misread as H - with no signal of uncertainty.
gen-atlas.ts now repaints K with a diagonal-legged bitmap: Hamming 8 from H,
and >=6 from every other ASCII glyph. Scoped to the narrow Spleen 5x8 primary
cell, so the JetBrains-Mono and CJK-fallback atlases are untouched. Zero
token-cost change - the glyph occupies the same 5x8 box.
Guarded by a regression test asserting no alphanumeric pair sits below
Hamming 2. Reproduce with: npx tsx eval/glyph-matrix/demo-glyph.mts
Closes the "optional glyph surgery" item in the 2026-07-01 legibility audit.
Several families share /v1/responses. Cost, geometry, cache rates, and
whether imaging is even allowed must follow the model that serves the
request. Otherwise Claude and Grok inherit GPT defaults, the gate lies,
and the dashboard reports nonsense.
Claude on Responses:
- Bill images by Anthropic pixel area; cache 0.1x, output 5x.
- Use Anthropic page geometry (312 cols x 728 px). GPT height overstated
image cost ~2.6x and flipped every Opus slab to not_profitable, so
enabled Claude stayed text-only with blank As text / Saved.
History profitability gate:
- Reflow packs hard newlines with an inline ↵ glyph. countVisualRows
still treated ↵ as a row break, so estimateImageCount overstated pages
~6x on reflowed history and collapsed Claude/Grok history never fired.
Match the renderer: only hard newlines start a visual row.
Grok:
- Keep production 5x8 packing and a verbatim fact-sheet for OCR-hard
tokens (paths/hex/ports/camelCase). Measured ~1000 image tok/MPix;
cache 0.25x, output 3x.
- Leave Grok out of DEFAULT_MODEL_BASES (opt-in only, same bar as Opus).
Pure-image exact OCR fails at 5x8; do not image it silently.
Also thread optional per-model render style through the Responses path
and allow eval-only atlas overrides in gen-atlas.
Fable 5 / Opus 4.8 accept up to 2576px / 4784 visual tokens per image, but a
request with >20 images (pxpipe always sends many) is held to the stricter
<=2000px/side rule, so the real ceiling is ~1932x1932 (1928x1928 = 69x69 = 4761
tokens). MAX_HEIGHT_PX 1568->1932; dense tool/history pages now render at
DENSE_CONTENT_COLS=384 / DENSE_CONTENT_CHARS_PER_IMAGE=92160 (1928x1928 full
page) -- fewer image blocks at the same OCR-validated 5x8 cell. The static slab
is unchanged (313 cols / 1573x1280).
Also fixes a regression the code review caught: the break-even gate,
truncateForBudget, and estimateImageCount predicted against the slab geometry
(313 cols / 159 rows) while the dense renderer emits 384 cols / 240 rows, so
large tool_results were truncated far earlier than the 10-image cap required --
silently dropping output that would have rendered. A per-page char budget is
threaded through the prediction chain (defaults to READABLE so the slab and unit
tests are byte-identical) plus a denseGateGeometry helper, so the gate prices the
same page the renderer actually produces.
Unifont glyphs are inherently 1-bit (every pixel is 0 or 255). Storing as
8-bit bytes wasted 7 bits per pixel.
Changes:
- scripts/gen-atlas.ts: emit ATLAS_PIXELS as bit-packed MSB-first. OFFSETS
now indexes bits not bytes. Per-cell paint thresholds R-channel at 128
defensively (Unifont is already 0/255).
- src/core/render.ts:blitGlyph: byte read replaced with bit extraction
(~3 extra ops per pixel; negligible). max() blending removed since bit
data is binary, no AA edges, no glyph overlap.
- src/core/atlas.ts: regenerated with the new format. Header comment
documents the bit-extraction formula.
- tests/render.test.ts: +1 structural assertion that ATLAS_PIXELS.byteLength
matches the bit-packed total.
Bundle size:
atlas.ts raw: 5.47 MB → 1.06 MB (5.2× shrink)
atlas.ts gzip: 1.55 MB → 479 KB (3.2× shrink)
dist gzipped: 1.57 MB → 488 KB (3.15× shrink, well under Workers
free-tier 1 MB cap)
Pre-deflate shrink is 8× (theoretical max). The 3.15× post-deflate
result reflects that deflate was already exploiting long runs of 0/255
in the 8-bit data; the bit-packed bytes are denser and less compressible.
Render output is byte-identical to pre-bit-pack (storage format change
only). 108/108 vitest, 4/4 shell tests, typecheck + build clean.
- Switch font: JetBrains Mono @ 15px → Unifont 16.0.04 @ 10px. Sparse
atlas with double-width EAW dispatch for CJK. Full BMP profile
(35,501 glyphs) covers Latin/Cyrillic/Greek/Hebrew/Arabic/CJK/Hangul
plus Letterlike, Misc Technical, Block Elements, Geometric Shapes,
Misc Symbols, Dingbats, Enclosed Alphanumerics, all box-drawing.
- Fix cell-height bug (was hardcoded 9; now probed from font metrics
via Math.ceil(maxAscent+maxDescent)). Previously clipped the top
2 rows off every CJK glyph since the original Unifont ship.
- Expand tabs to spaces with 4-column tab stops, EAW-aware. Was the
silent-drop source for 99.6% of dropped chars in production.
- Add dropped_codepoints_top telemetry (top 20 per event, only emitted
when drops > 0) so future coverage gaps surface in events.jsonl.
- Raise minToolResultChars 2000→5000 and minReminderChars 1000→2000
to stop net-losing tokens on small compressions, per ~2,500 tok/img
empirical measurement (N=33 cold-miss events).
- Fix dashboard per-image-cost formula: was pngBytes/375 (~190 tok),
now imageCount * 2500 (the measured empirical rate). Reduces the
inflated "tokens saved" headline to honest numbers.
- Schema-stub fix in compressSchemas path: preserveSchemaShell()
retains type / properties / required / enum / oneOf / anyOf / $ref /
numeric constraints recursively (depth 20), strips only descriptions
and metadata. Prevents 400 errors on first-tool-call requests.
- Capture full gzipped 4xx body + per-event req_body_sha8 for upstream
error diagnosis. Sidecar to ~/.pixelpipe/4xx-bodies/ when over 32 KB
inline cap. Workers-safe via CompressionStream + Web Crypto.
- scripts/restart.sh: pnpm-aware one-command kill+rebuild+start with
graceful SIGTERM→SIGKILL escalation, build-failure abort, port-in-use
precheck, --no-build flag for fast iteration. Shell-tested.
- Bundle 1.58 MB gzipped on Node. 91/91 vitest + 4/4 shell tests.
dhruvraajeev