Adds LINE (Bresenham in raster space, endpoints projected once each --
valid because the cavalier projection is linear), CIRCLE/ELLIPSE
(36-segment polygon approximation), and ARC (18 segments over a caller
radian range) to capsules/fabric.4th (blocks 4903-4912). TO-RASTER
factored out of CART-PLOT (same behavior) so LINE can reuse the
projection+flip for both endpoints.
Found mid-implementation: colon definitions cannot span block boundaries
in this capsule loader -- verified with a throwaway test capsule, the
continuation lands in a [CAPSULE][DEFER] path that never resolves. LINE's
body is split across LINE-SETUP/LINE-DONE?/LINE-STUCK?/LINE-STEP, each
self-contained within its block, rather than one long definition.
A fourth real bug, serious this time: CIRCLE's first live test rendered
only one quadrant, then hung the VM for several minutes on a follow-up
call. Root cause: q48_to_u64() (include/q48_16.h and
include/starkernel/q48_16.h, backing Q.TO-INT) did an unsigned logical
shift, corrupting any negative Q48.16 value into a huge garbage integer
instead of sign-extending -- inevitable once Q.SIN/Q.COS leave the first
quadrant. That garbage became a bogus LINE target with no bound on
LINE-STEP's Bresenham loop. Fixed q48_to_u64 to shift through a signed
int64_t intermediate (bit-identical for the non-negative case). Also added
LINE-STUCK? (LSTEPS vs FB-WIDTH+FB-HEIGHT, the true worst case for an
on-screen line) as a defense-in-depth cap against any future bad target.
Verified live on amd64 after both fixes: -65536 Q.TO-INT . now prints -1;
LINE/CIRCLE/ARC/ELLIPSE all complete without hanging or erroring, and a
combined screendump shows all four rendering correctly and distinctly.
All three architectures boot clean to ok> with the DoE completing;
dict_hash identical across all three and unchanged from 4.3.3a (expected
-- fabric.4th isn't loaded at boot, and the Q.TO-INT fix doesn't change
dictionary structure).
FABRIC.md item 4.3.3b marked done with full acceptance evidence.
Adds q48_reduce_angle() (range-reduce a signed Q48.16 angle into
[-PI_Q48, PI_Q48] via one integer division plus a bounded fix-up loop) and
q48_sin_approx/q48_cos_approx (Taylor series, terms n=3,5,7,9,11 for sin
and n=2,4,6,8,10 for cos, early exit below 10). Q.SIN/Q.COS registered as
FORTH words in q48_words.c, same pattern as Q.LOG/Q.EXP/Q.SQRT.
Found mid-implementation: this codebase has two independent Q48.16
implementations -- src/word_source/q48_16_words.c (hosted/vendored) and
src/starkernel/math/q48_16.c (kernel-only; the kernel build does not
compile the former at all). The hosted build linked fine after the first
pass; the kernel build failed with undefined references until the same
two functions were added to both .c files and both q48_16.h headers
(include/q48_16.h and include/starkernel/q48_16.h). Not fixed at the root
-- Q.LOG/Q.EXP/Q.SQRT already had this same four-file duplication,
unremarked until now -- just navigated correctly for this item.
Verified live on amd64 via serial injection: sin/cos at 0, +-pi/2, pi, and
3pi (range-reduction across multiple turns) all match expected values
within Taylor-series truncation error (<0.2%).
All three architectures boot clean to ok> with the DoE completing;
dict_hash identical across all three (0x291a660b05fa7b52).
FABRIC.md item 4.3.3a marked done with full acceptance evidence.
Adds Module 28 (framebuffer_words.c/.h): PLOT ( x y color -- ), FB-WIDTH,
FB-HEIGHT -- raw hardware-boundary C primitives, kernel-only, no-op on
hosted builds, same pattern as every other module.
Adds capsules/fabric.4th (blocks 4900-4902, mkcapsule --lint clean):
COS45/Z->DELTA/PROJECT/CART-Y/CART-PLOT -- the 45-degree cavalier
orthographic projection and Y-flip, in FORTH per the compose-in-FORTH-first
rule (this is policy, not hardware access).
Found and fixed a second real bug while live-testing CART-PLOT over the
serial socket: defining_word_variable() (defining_words.c) captured
vm->here as a VARIABLE's address with no alignment call first, while
vm_load_cell/vm_store_cell require 8-byte-aligned addresses. This capsule's
VARIABLE ZD landed misaligned (945) purely by chance of what preceded it;
other capsules' variables happened to land aligned by luck, not guarantee.
Real deviation from FORTH-83/ANS, which specifies VARIABLE reserves an
aligned cell. Fixed with vm_align(vm) before capturing addr -- ALIGN
already existed as a word but VARIABLE wasn't calling it.
Verified end-to-end on amd64 via manual serial injection + QEMU screendump:
plotted 4 marker points (origin, +100 X, +100 Y, +50 Z) and confirmed all
landed at hand-calculated raster coordinates, including the diagonal
up-right shift for the Z-axis point -- the projection math is correct, not
just non-crashing. fb/fabric-test-cart-plot.png. 4.3.1's corner diagnostic
still renders correctly in the same shot, confirming no regression.
All three architectures (amd64/aarch64/riscv64) boot clean to ok> with the
DoE completing; dict_hash identical across all three
(0xc7f9adf885e306d2), confirming parity is unaffected.
FABRIC.md item 4.3.3 marked done with full acceptance evidence.
Migrates Hermes's message/channel lifecycle onto the Stadium's unified
heat/capacity economy: MSG-ALLOC/FREE-NODE and CH-ALLOC/FREE-NODE now
route entirely through stadium_admit()/stadium_evict(), replacing the
old local free-list + independent heat-field mechanism. Eight
kernel-only STADIUM-* FORTH primitives (ADMIT, EVICT, RES@, RES-PULL,
RES-PUSH, HEAT@, HEAT!, WORD-HEAT), VM.stadium_vm_id threaded through
all three vm_core.c dispatch sites (replacing item 4.1's hardcoded
vm_uuid_hera()), and the stadium_owner[idx] fix so evict-credit lands
in the VM that actually admitted a patron, not whoever owned cell 0.
This session's own contribution, on top of that pre-existing
implementation: found and fixed two bugs blocking the item's own K≡1.0
conservation self-check (HERMES-K was reading 0, not 65536):
- Q.SLOT admission-heat fix (capsules/hermes/init.4th): MSG-SEND/
CH-ACCEPT admitted with Q.1 (the entire fleet-wide "1.0" unit) per
item, a leftover from before the Stadium migration when each
message/channel had its own unconstrained heat field. Instantly
drained the shared, finite reservoir.
- Reservoir floor for word-execution admission (stadium_words.c):
stadium_word_dispatch() (item 4.1) pulls STADIUM_WORD_HEAT_QUANTUM on
every word dispatch, not just first admission -- exhausts a VM's
entire reservoir in ~32 dispatches, starving any application-level
economy sharing that VM's reservoir before it gets a chance to pull
anything. word_dispatch_pull() now clamps word-execution's own pulls
to leave a Q48_ONE/3 floor (same fair-share figure COMMON-CH's own
floor already uses); application-level pulls are unaffected.
- STADIUM-WORD-HEAT primitive + stadium_words_resident_heat(): the
floor deliberately leaves word-execution residents holding real
heat, invisible to HERMES-K's original formula (MSG+CH+reservoir,
no term for word patrons). Adding this term closes K to exactly
65536 on all three architectures.
Also rules on two open scope questions in FABRIC.md: MBR-ALLOC/
MBR-FREE-NODE stay off the Stadium (membership records have no heat
field, never did -- the acceptance bullet's inclusion of them was a
completeness gesture predating a check of the actual layout), and
records the effort number (12 implementation files, +759/-120 lines).
Verified: all three architectures boot clean, full self-test passes,
Stadium conservation closes exactly (resident_sum + reservoir =
Q48_ONE) at both the C/Stadium level and the FORTH-level HERMES-K
check.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Punch list §25 item 4.1 complete.
Replaces the round-robin hotwords cache with Stadium density-ranked
admission/eviction on the kernel side, via the §17.7 reservoir mechanism and a
kernel-side word_id -> cell_index map (no DictEntry change, dict_hash
untouched). Adds stadium_birth_hera() to close the cell-0 panic hazard,
STADIUM_WORD_HEAT_QUANTUM/STADIUM_WORD_COOL_RATE_Q48 Kconfig knobs (flagged
untuned), and a stadium_word_forget() FORGET coherence hook to close a
recycled-word_id aliasing gap.
Verified: all five hotwords_cache_* call sites in dictionary_management.c
bypassed under __STARKERNEL__; word dispatch feeds the Stadium at all three
vm_core.c physics_execution_heat_increment() sites; hosted make unaffected;
all three architectures booted to ok> with matching dict_hash
(0x3d4e1daf289da94f) and matching conservation stats (promotions=354
evictions=0, resident_sum=65536 reservoir=0 sum=65536).
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Robert Allan James