fix(display): draw text 1-bit, so glyphs stay crisp on the LED grid - #521
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An LED panel has no partial brightness. PIL defaults ImageDraw's fontmode to "L", which anti-aliases TrueType glyphs into a grey fringe the panel can only round off -- a 4px glyph arrives smeared into 3px. DisplayManager creates its shared `draw` in six places and set fontmode at none of them, while _load_fonts loads extra_small_font as 4x6-font.ttf at size 6. Measured at draw time, that face at that size puts 74% of its lit pixels at partial coverage. Every plugin drawing small text through the shared draw inherited the blur; geochron was the case that surfaced it. The harness's VisualDisplayManager had the same gap, which mattered more than it looks: goldens were recording anti-aliased text that production would not produce, so the harness could not have caught this. Fixing only production left geochron still blurry under the harness -- that is how the second site was found. Both are set to "1" so the harness renders what the panel renders. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_014RRtqXDCnvnY6EQwhT5CV9
Up to standards ✅🟢 Issues |
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Included review availability: Your plan provides up to 1 included review per hour; 0 remain after this review. 📝 WalkthroughWalkthroughThe change sets Changes1-bit text rendering alignment
Estimated code review effort: 1 (Trivial) | ~5 minutes Merge Risk:⚪ Minimal · up to Text rendering now uses 1-bit glyphs in production and visual test canvases, eliminating partial-brightness text on LED panels while keeping visual test rendering aligned. The change is ready to merge. 🚥 Pre-merge checks | ✅ 5✅ Passed checks (5 passed)
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Codacy flagged the new code; it passes on other recent PRs, so the finding is mine. Four of the five broad `except Exception` clauses I added were catching far more than they needed to, which is the same shape as several bugs this branch fixes -- hello-world's TypeError sat invisible for exactly this reason. freezer() / move_to() / tick() -> (AttributeError, TypeError, ValueError) cache_manager.delete() -> (OSError, AttributeError, KeyError) The fifth stays broad and now says why: it wraps a call into a plugin's own display(), which can raise anything, and the first frame has already rendered -- so a failure there must not turn a good result into an error. Verified against a checkout of main: f1-scoreboard 48 PASS / 0 FAIL with 0 empty warnings, on-air keeps its 8 true positives, clock-simple 8 PASS. geochron shows 7 golden drifts both before and after this branch, so it is not from these changes -- its committed goldens predate #521's 1-bit text rendering.
…534) * fix(core): register tom_thumb, accept frame_hold in the test double, wire api_v3's managers Three independent fixes found while validating every plugin on a 256x64 rig. FontManager never registered tom_thumb even though assets/fonts/tom-thumb.bdf ships with the core, so every plugin offering it logged "Font family 'tom_thumb' not found" (16 warnings per countdown render) and had to carry a private loader to use a bundled font. Closes#524. VisualTestDisplayManager.set_scrolling_state() lacked the frame_hold parameter that DisplayManager gained, so any plugin passing it died with TypeError at render time and failed every size. Nine plugins now make that call; ledmatrix-stocks and ledmatrix-leaderboard were failing outright and the other seven only passed because their scroll path was unreachable without data. Closes#525. api_v3 declared module-level config_manager/plugin_manager = None that nothing ever assigned -- app.py sets the blueprint attributes, which the other 150+ call sites use. Three sites read the decoys, so /health reported the config unreadable and the plugin system uninitialised (making "degraded" permanent and unreachable-by-design) and /display/current fell back to a hardcoded 128x64 on every rig. The decoys are removed rather than assigned, so a bare name is now a NameError at test time instead of a silent None. The same function's first-call uptime was computed from two separate clock reads and came out negative. Closes#529. Verified on the rig: both previously-failing plugins render, the tom_thumb warnings are gone, /health reports "healthy" with all three checks passing, and /display/current reports the real 256x64. * fix(core): unique snapshot temp name, honour on-demand requests, skip empty starlark The preview snapshot wrote through a fixed "<snapshot>.tmp". /tmp is world-writable and sticky, and the display service runs as a different user from the tooling, so a leftover temp owned by anyone else became unopenable even by root -- fs.protected_regular refuses O_CREAT on a foreign file in a sticky directory. The preview and the health check's liveness proxy then froze until someone deleted the file by hand; on the test rig that meant 23 hours of a healthy display reporting "hardware: stale". Now uses tempfile.mkstemp with cleanup on failure, matching the hardware-status write a few hundred lines above. Closes#528. _poll_on_demand_requests read its mailbox with max_age=3600, and get() defaults the in-memory TTL to max_age -- so the first request was pinned in memory for an hour and every later poll returned that stale copy. No second on-demand request was honoured until the service restarted, while the API kept returning 200. get() already documents memory_ttl=0 for exactly this cross-process case. The consumed request is also now deleted: leaving it on disk meant a restart replayed the previous request, activated it, and ignored the one the caller had just made. Closes#530. starlark-apps returned None from display() when it has no app to show, which is the state of every install without Pixlet and of a fresh one before any app is added. The controller only skips on a boolean False, so that held a black panel for the full display_duration instead of rotating on. Closes#456 (core side). Verified on the rig: two consecutive on-demand requests with no restart between them are both activated, where the second was previously dropped in silence. * perf(harness): share one cache across a plugin's renders _instantiate built a fresh MockCacheManager for every (size, mode), and that mock is a per-instance in-memory dict, so each render was a cold start. A plugin that fetches per game or per player re-fetched everything N times over -- baseball-scoreboard at one size took 840s for nine renders where the arithmetic said ~72s, and at eight sizes it exceeded a 900s timeout. The second and later renders also never exercised the cache-hit path, which is what a running rig executes almost all of the time, so a caching regression could not be caught here. The cache is now built once per render_plugin_matrix call and threaded down. The display manager stays per-render -- the bounds checking depends on that -- so only fetched data is shared. Measured on the rig, same render counts and same goldens: tide-display 2s -> 1s (32 renders) cricket-scoreboard 10s -> 3s (24 renders) No pass/fail change across tide-display, cricket-scoreboard, clock-simple, geochron, christmas-countdown, of-the-day, web-ui-info and incoming-packages. Closes#533. * fix(scripts): run standalone plugin tests instead of collecting nothing run_plugin_tests.py discovered every plugin test file and handed the lot to pytest. Most plugin tests are standalone scripts -- module-level main() plus an `if __name__ == "__main__"` guard, signalling through an exit code -- and pytest collects zero items from those. The run printed how many files it had *found*, then "no tests ran", and exited without executing any of them. On a rig with all 44 first-party plugins that is 151 of 248 files. Files are now classified and each kind runs under the right runner: pytest for real test modules, subprocess for scripts, honouring the 0 pass / 2 skip / 1 fail convention ledmatrix-plugins' own runner established (a script that wants a tty or an LED matrix is a skip, not a regression). Before: $ python3 scripts/run_plugin_tests.py -p countdown -d ~/LEDMatrix/plugin-repos Found 1 test file(s) collected 0 items no tests ran in 0.31s rc=0 After: Found 1 test file(s) -- 0 collectable, 1 standalone script(s) 1 passed, 0 skipped, 0 failed (scripts) rc=0 Verified across three shapes: countdown (1 script), jellyfin-now-playing and pomodoro-timer (pytest only, 16 and 42 tests), and ledmatrix-flights (11 files split 4 collectable / 7 scripts, all seven of which had never run). Closes#532. Running the flights scripts for the first time also surfaced four genuinely failing tests there, hidden by the mirror-image bug in the plugins repo's own runner -- filed as ChuckBuilds/ledmatrix-plugins#464 and #465. * fix(harness): give an empty-looking mode a few frames before warning about it check_plugin's "drew nothing but display() returned X" warning fired on a single frame, rendered with force_clear=True, under a frozen clock. All three defeat a scrolling plugin, whose first frame is legitimately its blank scroll-in buffer. Across 44 first-party plugins, 60 of 76 warnings were false -- the rate at which people stop reading a warning, which matters because the true positives are real: a mode that draws nothing and does not return False holds a blank panel for its whole display duration. An apparently-empty frame is now re-driven for up to 48 more frames with force_clear=False (force_clear means "reset the scroll", so repeating it would redraw frame 1 for ever) and with the clock advancing -- freezegun's factory where time is frozen, a real sleep where it is not, since scroll position is usually a function of elapsed time. The first frame that draws content replaces the result. The clock is moved back afterwards. It is shared by every render in the matrix, so time borrowed by the probe leaked into later modes and drifted their goldens -- f1_upcoming picked up 5 spurious drifts before this was restored. Measured on the rig: empty warns check before after f1-scoreboard 42 0 48 PASS / 0 FAIL, goldens intact ledmatrix-elections 16 0 16 PASS / 0 FAIL on-air 8 8 true positive, kept nfl-draft 8 8 true positive, kept clock-simple/geochron/ 0 0 unchanged christmas-countdown 58 false positives gone, both true positives kept, no golden regressions. Cost is confined to modes that really are blank: plugins that draw immediately are unchanged (clock-simple and tide-display still 2s), while on-air -- eight deliberately blank modes -- goes to 21s. Closes#527. * fix(harness): load nested schema defaults, and merge caller config at leaf level load_config_defaults read only top-level properties. An object property carries its defaults on its children, not on itself, so everything nested was dropped -- 2,386 defaults across 37 of 44 plugins, soccer-scoreboard alone losing 539 of 565. render_plugin_matrix's comment says the plugin then "behaves like a real install", which for most of the fleet it did not. _defaults_from_properties now recurses. merge_config deep-merges the caller's config onto the result so an override lands at the leaf: a shallow merge would let -c '{"nhl": {"enabled": true}}' replace the whole nhl subtree and discard every other nhl default, which is the same class of bug being fixed here. Measured before/after across all 49 installed plugins on the rig: **no render changed** -- identical PASS/FAIL counts, byte-identical output, goldens intact. Plugins already fall back to the same values internally via config.get(key, default), so supplying them explicitly agrees with what they were doing. The defaults really are arriving now: ufc-scoreboard 9 -> 87 defaults ledmatrix-flights 51 -> 95 masters-tournament 10 -> 51 cricket-scoreboard 22 -> 50 tide-display 12 -> 18 and hockey-scoreboard, which used to load nhl.enabled=None, now gets nhl.enabled=True with its full display_modes block. Caveat worth carrying: the eight plugins with the most nested config (soccer, baseball, basketball, hockey, lacrosse, football, afl, nrl -- 1,634 of the 2,386 dropped defaults, 68%) could not be measured. They import src.common.sports_shared, which the test rig's core branch predates, so they fail to load there identically before and after. Re-run this comparison against a core that has that module before trusting the "nothing changed" result for them; those are exactly the plugins whose renders should change most. Closes#531. * refactor: narrow the exception handlers this branch introduced Codacy flagged the new code; it passes on other recent PRs, so the finding is mine. Four of the five broad `except Exception` clauses I added were catching far more than they needed to, which is the same shape as several bugs this branch fixes -- hello-world's TypeError sat invisible for exactly this reason. freezer() / move_to() / tick() -> (AttributeError, TypeError, ValueError) cache_manager.delete() -> (OSError, AttributeError, KeyError) The fifth stays broad and now says why: it wraps a call into a plugin's own display(), which can raise anything, and the first frame has already rendered -- so a failure there must not turn a good result into an error. Verified against a checkout of main: f1-scoreboard 48 PASS / 0 FAIL with 0 empty warnings, on-air keeps its 8 true positives, clock-simple 8 PASS. geochron shows 7 golden drifts both before and after this branch, so it is not from these changes -- its committed goldens predate #521's 1-bit text rendering. * fix: resolve CodeRabbit review and Codacy findings on #534 CodeRabbit raised six; all six were real. The test double had drifted ahead of production. VisualTestDisplayManager accepted set_scrolling_state(frame_hold=...) while DisplayManager did not, so such a call passed every harness run and would raise TypeError on the panel -- the one failure a safety harness exists to prevent. frame_hold belongs to the change that adds it to DisplayManager (#523), so it moves there and the double matches main again. The harness swallowed exceptions from re-rendered frames. _settle_loop re-renders a mode that came back blank, to give a scroll time to draw; returning silently on a crash meant a mode that renders one good frame and then explodes was reported as passing. Recorded on result.error now, keeping the captured frame so the failure stays inspectable. starlark-apps display() returned True after _display_frame() failed, so the controller held a dead frame for the whole display_duration instead of rotating on. _display_frame now returns bool on all three paths. run_plugin_tests.py used env.setdefault for PYTHONPATH and LEDMATRIX_CORE, so an inherited value won and the subprocess imported a different core than the one under test -- ledmatrix-plugins#467 exactly. Prepends PROJECT_ROOT and sets LEDMATRIX_CORE unconditionally. The on-demand mailbox is polled after every frame, ~125x/second on a scrolling mode, and the read is deliberately uncached, so it was that many disk reads per second to find nothing. Floored at 250ms, which is imperceptible for a web-UI click. Consuming it also deleted whatever was present rather than what had just been processed, so a request posted while the previous one was in flight was thrown away and never ran; the delete is now keyed by request_id. That narrows the window rather than closing it -- a true atomic claim needs a primitive the cache layer does not offer, and the code says so rather than implying otherwise. Codacy's 2 criticals were bandit B404/B603 on the subprocess call added to run_plugin_tests.py. Fixed interpreter, argument list, no shell; annotated with the repo's existing nosec convention. Bandit is clean on the file. Adds test/test_on_demand_mailbox.py (8), test_starlark_display_contract.py (4) and two settle cases in test_harness_empty_claimed.py. 4, 4 and 2 of those fail against the pre-fix code. Full suite: 3961 passed. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_014RRtqXDCnvnY6EQwhT5CV9 * chore: satisfy Codacy's subprocess checks on the new test runner Codacy runs Bandit and Opengrep (its Semgrep fork). The new subprocess.run in scripts/run_plugin_tests.py trips three patterns, on two different lines: Bandit B404 on the import, B603 on the call Opengrep dangerous-subprocess-use-audit on the run( line dangerous-subprocess-use-tainted-env-args on the argv line A nosemgrep applies only to its own line, so the call line and the argv line each need one; a single comment on the call covered neither rule fully. Suppression is the right answer here rather than a rewrite: the interpreter is sys.executable, the arguments are a list, and no shell is involved, so there is nothing to word-split or expand. Matches the pair the rest of the repo already uses for this shape -- permission_utils.py, plugin_loader.py, install_dependencies_apt.py. Codacy: 0 new issues, up to standards. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_014RRtqXDCnvnY6EQwhT5CV9 * chore: leave visual_display_manager untouched so #523 can merge The only change this branch made to that file was a docstring, and it collided with #523's rewrite of the same method -- so #534 and #523 each merged cleanly against main but conflicted with each other. Reverted to main's text; #523 owns this method and adds frame_hold to it. The note the docstring carried ('frame_hold arrives in #523') would have been stale the moment #523 landed anyway. The parity test in #523 is what actually keeps the two signatures honest. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_014RRtqXDCnvnY6EQwhT5CV9 * chore: add the Ruff suppression nosec/nosemgrep do not cover Ruff reports S603 on the same call Bandit and Opengrep do, and none of the three suppressions covers the others. Confirmed the precondition first: path comes from discover_plugin_tests(), which globs test files inside the repo, and the call is a fixed interpreter with a list argv and no shell. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_014RRtqXDCnvnY6EQwhT5CV9 --------- Co-authored-by: Claude Opus 5 (1M context) <noreply@anthropic.com>
The bug
An LED panel has no partial brightness. PIL defaults
ImageDraw'sfontmodeto"L", which anti-aliases TrueType glyphs into a grey fringe the panel can only round off — a 4px glyph arrives smeared into 3px.DisplayManagercreates its shareddrawin six places and setfontmodeat none of them, while_load_fontsloadsextra_small_fontas 4x6-font.ttf at size 6. Measured at draw time, that face at that size puts 74% of its lit pixels at partial coverage. Every plugin that draws small text through the shareddrawinherited the blur.The harness had the same gap, and that mattered more
src/plugin_system/testing/visual_display_manager.pycreates its owndrawin five places, also at the default. So the harness was recording anti-aliased goldens that production would never produce — it structurally could not have caught this.That is not a theoretical point. After the production fix,
geochronwas still rendering anti-aliased under the harness; tracing the draw object's creation stack led tovisual_display_manager.py:72. Fixing only production would have left the harness disagreeing with the panel.Both are now
"1", so the harness renders what the panel renders.Verification
A probe hooked
ImageDraw.textand recorded, for every real draw, thefontmodein effect, the font and size, the call site, and theDraw()object's creation site.Companion plugin-side PR: ChuckBuilds/ledmatrix-plugins#417.
🤖 Generated with Claude Code
https://claude.ai/code/session_014RRtqXDCnvnY6EQwhT5CV9
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