Add tools/scene_opcode_coverage.py: histograms a scene's static opcodes and
classifies each vs the C# VM as impl / safe-noop / GAP (effectful op the VM
silently stubs). Implemented set is parsed live from VirtualMachine.cs case arms
(no drift); metadata from build/opcodes.json. Makes a half-rendered scene legible
("N ops still stubbed") instead of implying everything runs.
SC0000 baseline: 129 distinct ops, ~94.8% instruction-weighted handled, 68 GAP.
The tracker cross-checks opcodes.toml vs VM behavior and surfaced 0x259
(script-entry marker) missing its noop_headless flag -> reconciled in opcodes.toml
and rebuilt (regen: age_opcodes_himegari.py, opcode-reference.md).
Docs: tools-reference.md (tool row), phase-a-slice-plan.md (completeness gauge).
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
VM dispatches on the opcodes.toml label field (OpcodeTableJson), so the 14 gfx
ops' labels are set to their dispatch strings. Ops still stubbed until the VM
cases land (Task 3.3+); full suite green (34), lint clean.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Ghidra-read all 13 still-stubbed gfx-family handlers via the dispatch table
(0x1a2/0x1f7/0x1fa/0x1ff/0x202/0x203/0x212/0x213/0x216/0x217/0x218/0x219/0x21a);
recovered 0x219 (was unanalyzed). Every op writes a cmd-type into the current
object record then SETs fields (native worker) or QUERYs fields (returns to
operands). Recorded the op-contract table in engine-re.md, set opcodes.toml
semantics (source=investigation, confidence=high), renamed handlers in Ghidra.
Key finding: the drift has TWO stubbed drivers, not one — 0x215 (slot-select)
AND 0x218/0x21a (per-object geometry vectors feeding the anchor-preserve math).
The subsystem is a per-object record model (slot + position/anchor 3-vectors +
color) queried by the ops; native DirectDraw workers need not be modelled. This
is the spec for Phase 2 (host-side model design).
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>